Class JList<E>
- java.lang.Object
-
- java.awt.Component
-
- java.awt.Container
-
- javax.swing.JComponent
-
- javax.swing.JList<E>
- Type Parameters:
-
E
- the type of the elements of this list
- All Implemented Interfaces:
-
ImageObserver
,MenuContainer
,Serializable
,Accessible
,Scrollable
@JavaBean(defaultProperty="UI", description="A component which allows for the selection of one or more objects from a list.") public class JList<E> extends JComponent implements Scrollable, Accessible
A component that displays a list of objects and allows the user to select one or more items. A separate model, ListModel
, maintains the contents of the list.
It's easy to display an array or Vector of objects, using the JList
constructor that automatically builds a read-only ListModel
instance for you:
// Create a JList that displays strings from an array String[] data = {"one", "two", "three", "four"}; JList<String> myList = new JList<String>(data); // Create a JList that displays the superclasses of JList.class, by // creating it with a Vector populated with this data Vector<Class<?>> superClasses = new Vector<Class<?>>(); Class<JList> rootClass = javax.swing.JList.class; for(Class<?> cls = rootClass; cls != null; cls = cls.getSuperclass()) { superClasses.addElement(cls); } JList<Class<?>> myList = new JList<Class<?>>(superClasses); // The automatically created model is stored in JList's "model" // property, which you can retrieve ListModel<Class<?>> model = myList.getModel(); for(int i = 0; i < model.getSize(); i++) { System.out.println(model.getElementAt(i)); }
A ListModel
can be supplied directly to a JList
by way of a constructor or the setModel
method. The contents need not be static - the number of items, and the values of items can change over time. A correct ListModel
implementation notifies the set of javax.swing.event.ListDataListener
s that have been added to it, each time a change occurs. These changes are characterized by a javax.swing.event.ListDataEvent
, which identifies the range of list indices that have been modified, added, or removed. JList
's ListUI
is responsible for keeping the visual representation up to date with changes, by listening to the model.
Simple, dynamic-content, JList
applications can use the DefaultListModel
class to maintain list elements. This class implements the ListModel
interface and also provides a java.util.Vector
-like API. Applications that need a more custom ListModel
implementation may instead wish to subclass AbstractListModel
, which provides basic support for managing and notifying listeners. For example, a read-only implementation of AbstractListModel
:
// This list model has about 2^16 elements. Enjoy scrolling. ListModel<String> bigData = new AbstractListModel<String>() { public int getSize() { return Short.MAX_VALUE; } public String getElementAt(int index) { return "Index " + index; } };
The selection state of a JList
is managed by another separate model, an instance of ListSelectionModel
. JList
is initialized with a selection model on construction, and also contains methods to query or set this selection model. Additionally, JList
provides convenient methods for easily managing the selection. These methods, such as setSelectedIndex
and getSelectedValue
, are cover methods that take care of the details of interacting with the selection model. By default, JList
's selection model is configured to allow any combination of items to be selected at a time; selection mode MULTIPLE_INTERVAL_SELECTION
. The selection mode can be changed on the selection model directly, or via JList
's cover method. Responsibility for updating the selection model in response to user gestures lies with the list's ListUI
.
A correct ListSelectionModel
implementation notifies the set of javax.swing.event.ListSelectionListener
s that have been added to it each time a change to the selection occurs. These changes are characterized by a javax.swing.event.ListSelectionEvent
, which identifies the range of the selection change.
The preferred way to listen for changes in list selection is to add ListSelectionListener
s directly to the JList
. JList
then takes care of listening to the selection model and notifying your listeners of change.
Responsibility for listening to selection changes in order to keep the list's visual representation up to date lies with the list's ListUI
.
Painting of cells in a JList
is handled by a delegate called a cell renderer, installed on the list as the cellRenderer
property. The renderer provides a java.awt.Component
that is used like a "rubber stamp" to paint the cells. Each time a cell needs to be painted, the list's ListUI
asks the cell renderer for the component, moves it into place, and has it paint the contents of the cell by way of its paint
method. A default cell renderer, which uses a JLabel
component to render, is installed by the lists's ListUI
. You can substitute your own renderer using code like this:
// Display an icon and a string for each object in the list. class MyCellRenderer extends JLabel implements ListCellRenderer<Object> { static final ImageIcon longIcon = new ImageIcon("long.gif"); static final ImageIcon shortIcon = new ImageIcon("short.gif"); // This is the only method defined by ListCellRenderer. // We just reconfigure the JLabel each time we're called. public Component getListCellRendererComponent( JList<?> list, // the list Object value, // value to display int index, // cell index boolean isSelected, // is the cell selected boolean cellHasFocus) // does the cell have focus { String s = value.toString(); setText(s); setIcon((s.length() > 10) ? longIcon : shortIcon); if (isSelected) { setBackground(list.getSelectionBackground()); setForeground(list.getSelectionForeground()); } else { setBackground(list.getBackground()); setForeground(list.getForeground()); } setEnabled(list.isEnabled()); setFont(list.getFont()); setOpaque(true); return this; } } myList.setCellRenderer(new MyCellRenderer());
Another job for the cell renderer is in helping to determine sizing information for the list. By default, the list's ListUI
determines the size of cells by asking the cell renderer for its preferred size for each list item. This can be expensive for large lists of items. To avoid these calculations, you can set a fixedCellWidth
and fixedCellHeight
on the list, or have these values calculated automatically based on a single prototype value:
JList<String> bigDataList = new JList<String>(bigData); // We don't want the JList implementation to compute the width // or height of all of the list cells, so we give it a string // that's as big as we'll need for any cell. It uses this to // compute values for the fixedCellWidth and fixedCellHeight // properties. bigDataList.setPrototypeCellValue("Index 1234567890");
JList
doesn't implement scrolling directly. To create a list that scrolls, make it the viewport view of a JScrollPane
. For example:
JScrollPane scrollPane = new JScrollPane(myList); // Or in two steps: JScrollPane scrollPane = new JScrollPane(); scrollPane.getViewport().setView(myList);
JList
doesn't provide any special handling of double or triple (or N) mouse clicks, but it's easy to add a MouseListener
if you wish to take action on these events. Use the locationToIndex
method to determine what cell was clicked. For example:
MouseListener mouseListener = new MouseAdapter() { public void mouseClicked(MouseEvent e) { if (e.getClickCount() == 2) { int index = list.locationToIndex(e.getPoint()); System.out.println("Double clicked on Item " + index); } } }; list.addMouseListener(mouseListener);
Warning: Swing is not thread safe. For more information see Swing's Threading Policy.
Warning: Serialized objects of this class will not be compatible with future Swing releases. The current serialization support is appropriate for short term storage or RMI between applications running the same version of Swing. As of 1.4, support for long term storage of all JavaBeans™ has been added to the java.beans
package. Please see XMLEncoder
.
See How to Use Lists in The Java Tutorial for further documentation.
- Since:
- 1.2
- See Also:
-
ListModel
,AbstractListModel
,DefaultListModel
,ListSelectionModel
,DefaultListSelectionModel
,ListCellRenderer
,DefaultListCellRenderer
, Serialized Form
Nested Class Summary
Modifier and Type | Class | Description |
---|---|---|
protected class | JList.AccessibleJList | This class implements accessibility support for the |
static class | JList.DropLocation | A subclass of |
Nested classes/interfaces declared in class javax.swing.JComponent
JComponent.AccessibleJComponent
Nested classes/interfaces declared in class java.awt.Container
Container.AccessibleAWTContainer
Nested classes/interfaces declared in class java.awt.Component
Component.AccessibleAWTComponent, Component.BaselineResizeBehavior, Component.BltBufferStrategy, Component.FlipBufferStrategy
Field Summary
Modifier and Type | Field | Description |
---|---|---|
static int | HORIZONTAL_WRAP | Indicates a "newspaper style" layout with cells flowing horizontally then vertically. |
static int | VERTICAL | Indicates a vertical layout of cells, in a single column; the default layout. |
static int | VERTICAL_WRAP | Indicates a "newspaper style" layout with cells flowing vertically then horizontally. |
Fields declared in class javax.swing.JComponent
listenerList, TOOL_TIP_TEXT_KEY, ui, UNDEFINED_CONDITION, WHEN_ANCESTOR_OF_FOCUSED_COMPONENT, WHEN_FOCUSED, WHEN_IN_FOCUSED_WINDOW
Fields declared in class java.awt.Component
accessibleContext, BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT
Fields declared in interface java.awt.image.ImageObserver
ABORT, ALLBITS, ERROR, FRAMEBITS, HEIGHT, PROPERTIES, SOMEBITS, WIDTH
Constructor Summary
Constructor | Description |
---|---|
JList() | Constructs a |
JList(E[] listData) | Constructs a |
JList(Vector<? extends E> listData) | Constructs a |
JList(ListModel<E> dataModel) | Constructs a |
Method Summary
Modifier and Type | Method | Description |
---|---|---|
void | addListSelectionListener(ListSelectionListener listener) | Adds a listener to the list, to be notified each time a change to the selection occurs; the preferred way of listening for selection state changes. |
void | addSelectionInterval(int anchor,
int lead) | Sets the selection to be the union of the specified interval with current selection. |
void | clearSelection() | Clears the selection; after calling this method, |
protected ListSelectionModel | createSelectionModel() | Returns an instance of |
void | ensureIndexIsVisible(int index) | Scrolls the list within an enclosing viewport to make the specified cell completely visible. |
protected void | fireSelectionValueChanged(int firstIndex,
int lastIndex,
boolean isAdjusting) | Notifies |
AccessibleContext | getAccessibleContext() | Gets the |
int | getAnchorSelectionIndex() | Returns the anchor selection index. |
Rectangle | getCellBounds(int index0,
int index1) | Returns the bounding rectangle, in the list's coordinate system, for the range of cells specified by the two indices. |
ListCellRenderer<? super E> | getCellRenderer() | Returns the object responsible for painting list items. |
boolean | getDragEnabled() | Returns whether or not automatic drag handling is enabled. |
JList.DropLocation | getDropLocation() | Returns the location that this component should visually indicate as the drop location during a DnD operation over the component, or |
DropMode | getDropMode() | Returns the drop mode for this component. |
int | getFirstVisibleIndex() | Returns the smallest list index that is currently visible. |
int | getFixedCellHeight() | Returns the value of the |
int | getFixedCellWidth() | Returns the value of the |
int | getLastVisibleIndex() | Returns the largest list index that is currently visible. |
int | getLayoutOrientation() | Returns the layout orientation property for the list: |
int | getLeadSelectionIndex() | Returns the lead selection index. |
ListSelectionListener[] | getListSelectionListeners() | Returns an array of all the |
int | getMaxSelectionIndex() | Returns the largest selected cell index, or |
int | getMinSelectionIndex() | Returns the smallest selected cell index, or |
ListModel<E> | getModel() | Returns the data model that holds the list of items displayed by the |
int | getNextMatch(String prefix,
int startIndex,
Position.Bias bias) | Returns the next list element whose |
Dimension | getPreferredScrollableViewportSize() | Computes the size of viewport needed to display |
E | getPrototypeCellValue() | Returns the "prototypical" cell value -- a value used to calculate a fixed width and height for cells. |
int | getScrollableBlockIncrement(Rectangle visibleRect,
int orientation,
int direction) | Returns the distance to scroll to expose the next or previous block. |
boolean | getScrollableTracksViewportHeight() | Returns |
boolean | getScrollableTracksViewportWidth() | Returns |
int | getScrollableUnitIncrement(Rectangle visibleRect,
int orientation,
int direction) | Returns the distance to scroll to expose the next or previous row (for vertical scrolling) or column (for horizontal scrolling). |
int | getSelectedIndex() | Returns the smallest selected cell index; the selection when only a single item is selected in the list. |
int[] | getSelectedIndices() | Returns an array of all of the selected indices, in increasing order. |
E | getSelectedValue() | Returns the value for the smallest selected cell index; the selected value when only a single item is selected in the list. |
Object[] | getSelectedValues() | Deprecated. As of JDK 1.7, replaced by getSelectedValuesList()
|
List<E> | getSelectedValuesList() | Returns a list of all the selected items, in increasing order based on their indices in the list. |
Color | getSelectionBackground() | Returns the color used to draw the background of selected items. |
Color | getSelectionForeground() | Returns the color used to draw the foreground of selected items. |
int | getSelectionMode() | Returns the current selection mode for the list. |
ListSelectionModel | getSelectionModel() | Returns the current selection model. |
String | getToolTipText(MouseEvent event) | Returns the tooltip text to be used for the given event. |
ListUI | getUI() | Returns the |
String | getUIClassID() | Returns |
boolean | getValueIsAdjusting() | Returns the value of the selection model's |
int | getVisibleRowCount() | Returns the value of the |
Point | indexToLocation(int index) | Returns the origin of the specified item in the list's coordinate system. |
boolean | isSelectedIndex(int index) | Returns |
boolean | isSelectionEmpty() | Returns |
int | locationToIndex(Point location) | Returns the cell index closest to the given location in the list's coordinate system. |
protected String | paramString() | Returns a |
void | removeListSelectionListener(ListSelectionListener listener) | Removes a selection listener from the list. |
void | removeSelectionInterval(int index0,
int index1) | Sets the selection to be the set difference of the specified interval and the current selection. |
void | setCellRenderer(ListCellRenderer<? super E> cellRenderer) | Sets the delegate that is used to paint each cell in the list. |
void | setDragEnabled(boolean b) | Turns on or off automatic drag handling. |
void | setDropMode(DropMode dropMode) | Sets the drop mode for this component. |
void | setFixedCellHeight(int height) | Sets a fixed value to be used for the height of every cell in the list. |
void | setFixedCellWidth(int width) | Sets a fixed value to be used for the width of every cell in the list. |
void | setLayoutOrientation(int layoutOrientation) | Defines the way list cells are layed out. |
void | setListData(E[] listData) | Constructs a read-only |
void | setListData(Vector<? extends E> listData) | Constructs a read-only |
void | setModel(ListModel<E> model) | Sets the model that represents the contents or "value" of the list, notifies property change listeners, and then clears the list's selection. |
void | setPrototypeCellValue(E prototypeCellValue) | Sets the |
void | setSelectedIndex(int index) | Selects a single cell. |
void | setSelectedIndices(int[] indices) | Changes the selection to be the set of indices specified by the given array. |
void | setSelectedValue(Object anObject,
boolean shouldScroll) | Selects the specified object from the list. |
void | setSelectionBackground(Color selectionBackground) | Sets the color used to draw the background of selected items, which cell renderers can use fill selected cells. |
void | setSelectionForeground(Color selectionForeground) | Sets the color used to draw the foreground of selected items, which cell renderers can use to render text and graphics. |
void | setSelectionInterval(int anchor,
int lead) | Selects the specified interval. |
void | setSelectionMode(int selectionMode) | Sets the selection mode for the list. |
void | setSelectionModel(ListSelectionModel selectionModel) | Sets the |
void | setUI(ListUI ui) | Sets the |
void | setValueIsAdjusting(boolean b) | Sets the selection model's |
void | setVisibleRowCount(int visibleRowCount) | Sets the |
void | updateUI() | Resets the |
Methods declared in class javax.swing.JComponent
addAncestorListener, addNotify, addVetoableChangeListener, computeVisibleRect, contains, createToolTip, disable, enable, firePropertyChange, firePropertyChange, fireVetoableChange, getActionForKeyStroke, getActionMap, getAlignmentX, getAlignmentY, getAncestorListeners, getAutoscrolls, getBaseline, getBaselineResizeBehavior, getBorder, getBounds, getClientProperty, getComponentGraphics, getComponentPopupMenu, getConditionForKeyStroke, getDebugGraphicsOptions, getDefaultLocale, getFontMetrics, getGraphics, getHeight, getInheritsPopupMenu, getInputMap, getInputMap, getInputVerifier, getInsets, getInsets, getListeners, getLocation, getMaximumSize, getMinimumSize, getNextFocusableComponent, getPopupLocation, getPreferredSize, getRegisteredKeyStrokes, getRootPane, getSize, getToolTipLocation, getToolTipText, getTopLevelAncestor, getTransferHandler, getVerifyInputWhenFocusTarget, getVetoableChangeListeners, getVisibleRect, getWidth, getX, getY, grabFocus, isDoubleBuffered, isLightweightComponent, isManagingFocus, isOpaque, isOptimizedDrawingEnabled, isPaintingForPrint, isPaintingOrigin, isPaintingTile, isRequestFocusEnabled, isValidateRoot, paint, paintBorder, paintChildren, paintComponent, paintImmediately, paintImmediately, print, printAll, printBorder, printChildren, printComponent, processComponentKeyEvent, processKeyBinding, processKeyEvent, processMouseEvent, processMouseMotionEvent, putClientProperty, registerKeyboardAction, registerKeyboardAction, removeAncestorListener, removeNotify, removeVetoableChangeListener, repaint, repaint, requestDefaultFocus, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, resetKeyboardActions, reshape, revalidate, scrollRectToVisible, setActionMap, setAlignmentX, setAlignmentY, setAutoscrolls, setBackground, setBorder, setComponentPopupMenu, setDebugGraphicsOptions, setDefaultLocale, setDoubleBuffered, setEnabled, setFocusTraversalKeys, setFont, setForeground, setInheritsPopupMenu, setInputMap, setInputVerifier, setMaximumSize, setMinimumSize, setNextFocusableComponent, setOpaque, setPreferredSize, setRequestFocusEnabled, setToolTipText, setTransferHandler, setUI, setVerifyInputWhenFocusTarget, setVisible, unregisterKeyboardAction, update
Methods declared in class java.awt.Container
add, add, add, add, add, addContainerListener, addImpl, addPropertyChangeListener, addPropertyChangeListener, applyComponentOrientation, areFocusTraversalKeysSet, countComponents, deliverEvent, doLayout, findComponentAt, findComponentAt, getComponent, getComponentAt, getComponentAt, getComponentCount, getComponents, getComponentZOrder, getContainerListeners, getFocusTraversalKeys, getFocusTraversalPolicy, getLayout, getMousePosition, insets, invalidate, isAncestorOf, isFocusCycleRoot, isFocusCycleRoot, isFocusTraversalPolicyProvider, isFocusTraversalPolicySet, layout, list, list, locate, minimumSize, paintComponents, preferredSize, printComponents, processContainerEvent, processEvent, remove, remove, removeAll, removeContainerListener, setComponentZOrder, setFocusCycleRoot, setFocusTraversalPolicy, setFocusTraversalPolicyProvider, setLayout, transferFocusDownCycle, validate, validateTree
Methods declared in class java.awt.Component
action, add, addComponentListener, addFocusListener, addHierarchyBoundsListener, addHierarchyListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, addMouseWheelListener, bounds, checkImage, checkImage, coalesceEvents, contains, createImage, createImage, createVolatileImage, createVolatileImage, disableEvents, dispatchEvent, enable, enableEvents, enableInputMethods, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, getBackground, getBounds, getColorModel, getComponentListeners, getComponentOrientation, getCursor, getDropTarget, getFocusCycleRootAncestor, getFocusListeners, getFocusTraversalKeysEnabled, getFont, getForeground, getGraphicsConfiguration, getHierarchyBoundsListeners, getHierarchyListeners, getIgnoreRepaint, getInputContext, getInputMethodListeners, getInputMethodRequests, getKeyListeners, getLocale, getLocation, getLocationOnScreen, getMouseListeners, getMouseMotionListeners, getMousePosition, getMouseWheelListeners, getName, getParent, getPropertyChangeListeners, getPropertyChangeListeners, getSize, getToolkit, getTreeLock, gotFocus, handleEvent, hasFocus, hide, imageUpdate, inside, isBackgroundSet, isCursorSet, isDisplayable, isEnabled, isFocusable, isFocusOwner, isFocusTraversable, isFontSet, isForegroundSet, isLightweight, isMaximumSizeSet, isMinimumSizeSet, isPreferredSizeSet, isShowing, isValid, isVisible, keyDown, keyUp, list, list, list, location, lostFocus, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paintAll, postEvent, prepareImage, prepareImage, processComponentEvent, processFocusEvent, processHierarchyBoundsEvent, processHierarchyEvent, processInputMethodEvent, processMouseWheelEvent, remove, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, requestFocus, requestFocus, requestFocusInWindow, resize, resize, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setFocusable, setFocusTraversalKeysEnabled, setIgnoreRepaint, setLocale, setLocation, setLocation, setMixingCutoutShape, setName, setSize, setSize, show, show, size, toString, transferFocus, transferFocusBackward, transferFocusUpCycle
Methods declared in class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
Field Detail
VERTICAL
public static final int VERTICAL
Indicates a vertical layout of cells, in a single column; the default layout.
- Since:
- 1.4
- See Also:
-
setLayoutOrientation(int)
, Constant Field Values
VERTICAL_WRAP
public static final int VERTICAL_WRAP
Indicates a "newspaper style" layout with cells flowing vertically then horizontally.
- Since:
- 1.4
- See Also:
-
setLayoutOrientation(int)
, Constant Field Values
HORIZONTAL_WRAP
public static final int HORIZONTAL_WRAP
Indicates a "newspaper style" layout with cells flowing horizontally then vertically.
- Since:
- 1.4
- See Also:
-
setLayoutOrientation(int)
, Constant Field Values
Constructor Detail
JList
public JList(ListModel<E> dataModel)
Constructs a JList
that displays elements from the specified, non-null
, model. All JList
constructors delegate to this one.
This constructor registers the list with the ToolTipManager
, allowing for tooltips to be provided by the cell renderers.
- Parameters:
-
dataModel
- the model for the list - Throws:
-
IllegalArgumentException
- if the model isnull
JList
public JList(E[] listData)
Constructs a JList
that displays the elements in the specified array. This constructor creates a read-only model for the given array, and then delegates to the constructor that takes a ListModel
.
Attempts to pass a null
value to this method results in undefined behavior and, most likely, exceptions. The created model references the given array directly. Attempts to modify the array after constructing the list results in undefined behavior.
- Parameters:
-
listData
- the array of Objects to be loaded into the data model,non-null
JList
public JList(Vector<? extends E> listData)
Constructs a JList
that displays the elements in the specified Vector
. This constructor creates a read-only model for the given Vector
, and then delegates to the constructor that takes a ListModel
.
Attempts to pass a null
value to this method results in undefined behavior and, most likely, exceptions. The created model references the given Vector
directly. Attempts to modify the Vector
after constructing the list results in undefined behavior.
- Parameters:
-
listData
- theVector
to be loaded into the data model,non-null
JList
public JList()
Constructs a JList
with an empty, read-only, model.
Method Detail
getUI
public ListUI getUI()
Returns the ListUI
, the look and feel object that renders this component.
- Overrides:
-
getUI
in classJComponent
- Returns:
- the
ListUI
object that renders this component
setUI
@BeanProperty(hidden=true, visualUpdate=true, description="The UI object that implements the Component\'s LookAndFeel.") public void setUI(ListUI ui)
Sets the ListUI
, the look and feel object that renders this component.
- Parameters:
-
ui
- theListUI
object - See Also:
UIDefaults.getUI(javax.swing.JComponent)
updateUI
public void updateUI()
Resets the ListUI
property by setting it to the value provided by the current look and feel. If the current cell renderer was installed by the developer (rather than the look and feel itself), this also causes the cell renderer and its children to be updated, by calling SwingUtilities.updateComponentTreeUI
on it.
- Overrides:
-
updateUI
in classJComponent
- See Also:
-
UIManager.getUI(javax.swing.JComponent)
,SwingUtilities.updateComponentTreeUI(java.awt.Component)
getUIClassID
@BeanProperty(bound=false) public String getUIClassID()
Returns "ListUI"
, the UIDefaults
key used to look up the name of the javax.swing.plaf.ListUI
class that defines the look and feel for this component.
- Overrides:
-
getUIClassID
in classJComponent
- Returns:
- the string "ListUI"
- See Also:
-
JComponent.getUIClassID()
,UIDefaults.getUI(javax.swing.JComponent)
getPrototypeCellValue
public E getPrototypeCellValue()
Returns the "prototypical" cell value -- a value used to calculate a fixed width and height for cells. This can be null
if there is no such value.
- Returns:
- the value of the
prototypeCellValue
property - See Also:
setPrototypeCellValue(E)
setPrototypeCellValue
@BeanProperty(visualUpdate=true, description="The cell prototype value, used to compute cell width and height.") public void setPrototypeCellValue(E prototypeCellValue)
Sets the prototypeCellValue
property, and then (if the new value is non-null
), computes the fixedCellWidth
and fixedCellHeight
properties by requesting the cell renderer component for the given value (and index 0) from the cell renderer, and using that component's preferred size.
This method is useful when the list is too long to allow the ListUI
to compute the width/height of each cell, and there is a single cell value that is known to occupy as much space as any of the others, a so-called prototype.
While all three of the prototypeCellValue
, fixedCellHeight
, and fixedCellWidth
properties may be modified by this method, PropertyChangeEvent
notifications are only sent when the prototypeCellValue
property changes.
To see an example which sets this property, see the class description above.
The default value of this property is null
.
This is a JavaBeans bound property.
- Parameters:
-
prototypeCellValue
- the value on which to basefixedCellWidth
andfixedCellHeight
- See Also:
-
getPrototypeCellValue()
,setFixedCellWidth(int)
,setFixedCellHeight(int)
,Container.addPropertyChangeListener(java.beans.PropertyChangeListener)
getFixedCellWidth
public int getFixedCellWidth()
Returns the value of the fixedCellWidth
property.
- Returns:
- the fixed cell width
- See Also:
setFixedCellWidth(int)
setFixedCellWidth
@BeanProperty(visualUpdate=true, description="Defines a fixed cell width when greater than zero.") public void setFixedCellWidth(int width)
Sets a fixed value to be used for the width of every cell in the list. If width
is -1, cell widths are computed in the ListUI
by applying getPreferredSize
to the cell renderer component for each list element.
The default value of this property is -1
.
This is a JavaBeans bound property.
- Parameters:
-
width
- the width to be used for all cells in the list - See Also:
-
setPrototypeCellValue(E)
,setFixedCellWidth(int)
,Container.addPropertyChangeListener(java.beans.PropertyChangeListener)
getFixedCellHeight
public int getFixedCellHeight()
Returns the value of the fixedCellHeight
property.
- Returns:
- the fixed cell height
- See Also:
setFixedCellHeight(int)
setFixedCellHeight
@BeanProperty(visualUpdate=true, description="Defines a fixed cell height when greater than zero.") public void setFixedCellHeight(int height)
Sets a fixed value to be used for the height of every cell in the list. If height
is -1, cell heights are computed in the ListUI
by applying getPreferredSize
to the cell renderer component for each list element.
The default value of this property is -1
.
This is a JavaBeans bound property.
- Parameters:
-
height
- the height to be used for all cells in the list - See Also:
-
setPrototypeCellValue(E)
,setFixedCellWidth(int)
,Container.addPropertyChangeListener(java.beans.PropertyChangeListener)
getCellRenderer
public ListCellRenderer<? super E> getCellRenderer()
Returns the object responsible for painting list items.
- Returns:
- the value of the
cellRenderer
property - See Also:
setCellRenderer(javax.swing.ListCellRenderer<? super E>)
setCellRenderer
@BeanProperty(visualUpdate=true, description="The component used to draw the cells.") public void setCellRenderer(ListCellRenderer<? super E> cellRenderer)
Sets the delegate that is used to paint each cell in the list. The job of a cell renderer is discussed in detail in the class level documentation.
If the prototypeCellValue
property is non-null
, setting the cell renderer also causes the fixedCellWidth
and fixedCellHeight
properties to be re-calculated. Only one PropertyChangeEvent
is generated however - for the cellRenderer
property.
The default value of this property is provided by the ListUI
delegate, i.e. by the look and feel implementation.
This is a JavaBeans bound property.
- Parameters:
-
cellRenderer
- theListCellRenderer
that paints list cells - See Also:
getCellRenderer()
getSelectionForeground
public Color getSelectionForeground()
Returns the color used to draw the foreground of selected items. DefaultListCellRenderer
uses this color to draw the foreground of items in the selected state, as do the renderers installed by most ListUI
implementations.
- Returns:
- the color to draw the foreground of selected items
- See Also:
-
setSelectionForeground(java.awt.Color)
,DefaultListCellRenderer
setSelectionForeground
@BeanProperty(visualUpdate=true, description="The foreground color of selected cells.") public void setSelectionForeground(Color selectionForeground)
Sets the color used to draw the foreground of selected items, which cell renderers can use to render text and graphics. DefaultListCellRenderer
uses this color to draw the foreground of items in the selected state, as do the renderers installed by most ListUI
implementations.
The default value of this property is defined by the look and feel implementation.
This is a JavaBeans bound property.
- Parameters:
-
selectionForeground
- theColor
to use in the foreground for selected list items - See Also:
-
getSelectionForeground()
,setSelectionBackground(java.awt.Color)
,JComponent.setForeground(java.awt.Color)
,JComponent.setBackground(java.awt.Color)
,JComponent.setFont(java.awt.Font)
,DefaultListCellRenderer
getSelectionBackground
public Color getSelectionBackground()
Returns the color used to draw the background of selected items. DefaultListCellRenderer
uses this color to draw the background of items in the selected state, as do the renderers installed by most ListUI
implementations.
- Returns:
- the color to draw the background of selected items
- See Also:
-
setSelectionBackground(java.awt.Color)
,DefaultListCellRenderer
setSelectionBackground
@BeanProperty(visualUpdate=true, description="The background color of selected cells.") public void setSelectionBackground(Color selectionBackground)
Sets the color used to draw the background of selected items, which cell renderers can use fill selected cells. DefaultListCellRenderer
uses this color to fill the background of items in the selected state, as do the renderers installed by most ListUI
implementations.
The default value of this property is defined by the look and feel implementation.
This is a JavaBeans bound property.
- Parameters:
-
selectionBackground
- theColor
to use for the background of selected cells - See Also:
-
getSelectionBackground()
,setSelectionForeground(java.awt.Color)
,JComponent.setForeground(java.awt.Color)
,JComponent.setBackground(java.awt.Color)
,JComponent.setFont(java.awt.Font)
,DefaultListCellRenderer
getVisibleRowCount
public int getVisibleRowCount()
Returns the value of the visibleRowCount
property. See the documentation for setVisibleRowCount(int)
for details on how to interpret this value.
- Returns:
- the value of the
visibleRowCount
property. - See Also:
setVisibleRowCount(int)
setVisibleRowCount
@BeanProperty(visualUpdate=true, description="The preferred number of rows to display without requiring scrolling") public void setVisibleRowCount(int visibleRowCount)
Sets the visibleRowCount
property, which has different meanings depending on the layout orientation: For a VERTICAL
layout orientation, this sets the preferred number of rows to display without requiring scrolling; for other orientations, it affects the wrapping of cells.
In VERTICAL
orientation:
Setting this property affects the return value of the getPreferredScrollableViewportSize()
method, which is used to calculate the preferred size of an enclosing viewport. See that method's documentation for more details.
In HORIZONTAL_WRAP
and VERTICAL_WRAP
orientations:
This affects how cells are wrapped. See the documentation of setLayoutOrientation(int)
for more details.
The default value of this property is 8
.
Calling this method with a negative value results in the property being set to 0
.
This is a JavaBeans bound property.
- Parameters:
-
visibleRowCount
- an integer specifying the preferred number of rows to display without requiring scrolling - See Also:
-
getVisibleRowCount()
,getPreferredScrollableViewportSize()
,setLayoutOrientation(int)
,JComponent.getVisibleRect()
,JViewport
getLayoutOrientation
public int getLayoutOrientation()
Returns the layout orientation property for the list: VERTICAL
if the layout is a single column of cells, VERTICAL_WRAP
if the layout is "newspaper style" with the content flowing vertically then horizontally, or HORIZONTAL_WRAP
if the layout is "newspaper style" with the content flowing horizontally then vertically.
- Returns:
- the value of the
layoutOrientation
property - Since:
- 1.4
- See Also:
setLayoutOrientation(int)
setLayoutOrientation
@BeanProperty(visualUpdate=true, enumerationValues={"JList.VERTICAL","JList.HORIZONTAL_WRAP","JList.VERTICAL_WRAP"}, description="Defines the way list cells are layed out.") public void setLayoutOrientation(int layoutOrientation)
Defines the way list cells are layed out. Consider a JList
with five cells. Cells can be layed out in one of the following ways:
VERTICAL: 0 1 2 3 4 HORIZONTAL_WRAP: 0 1 2 3 4 VERTICAL_WRAP: 0 3 1 4 2
A description of these layouts follows:
Value | Description |
---|---|
VERTICAL |
Cells are layed out vertically in a single column. |
HORIZONTAL_WRAP |
Cells are layed out horizontally, wrapping to a new row as necessary. If the visibleRowCount property is less than or equal to zero, wrapping is determined by the width of the list; otherwise wrapping is done in such a way as to ensure visibleRowCount rows in the list. |
VERTICAL_WRAP |
Cells are layed out vertically, wrapping to a new column as necessary. If the visibleRowCount property is less than or equal to zero, wrapping is determined by the height of the list; otherwise wrapping is done at visibleRowCount rows. |
VERTICAL
.- Parameters:
-
layoutOrientation
- the new layout orientation, one of:VERTICAL
,HORIZONTAL_WRAP
orVERTICAL_WRAP
- Throws:
-
IllegalArgumentException
- iflayoutOrientation
isn't one of the allowable values - Since:
- 1.4
- See Also:
-
getLayoutOrientation()
,setVisibleRowCount(int)
,getScrollableTracksViewportHeight()
,getScrollableTracksViewportWidth()
getFirstVisibleIndex
@BeanProperty(bound=false) public int getFirstVisibleIndex()
Returns the smallest list index that is currently visible. In a left-to-right componentOrientation
, the first visible cell is found closest to the list's upper-left corner. In right-to-left orientation, it is found closest to the upper-right corner. If nothing is visible or the list is empty, -1
is returned. Note that the returned cell may only be partially visible.
- Returns:
- the index of the first visible cell
- See Also:
-
getLastVisibleIndex()
,JComponent.getVisibleRect()
getLastVisibleIndex
@BeanProperty(bound=false) public int getLastVisibleIndex()
Returns the largest list index that is currently visible. If nothing is visible or the list is empty, -1
is returned. Note that the returned cell may only be partially visible.
- Returns:
- the index of the last visible cell
- See Also:
-
getFirstVisibleIndex()
,JComponent.getVisibleRect()
ensureIndexIsVisible
public void ensureIndexIsVisible(int index)
Scrolls the list within an enclosing viewport to make the specified cell completely visible. This calls scrollRectToVisible
with the bounds of the specified cell. For this method to work, the JList
must be within a JViewport
.
If the given index is outside the list's range of cells, this method results in nothing.
- Parameters:
-
index
- the index of the cell to make visible - See Also:
-
JComponent.scrollRectToVisible(java.awt.Rectangle)
,JComponent.getVisibleRect()
setDragEnabled
@BeanProperty(bound=false, description="determines whether automatic drag handling is enabled") public void setDragEnabled(boolean b)
Turns on or off automatic drag handling. In order to enable automatic drag handling, this property should be set to true
, and the list's TransferHandler
needs to be non-null
. The default value of the dragEnabled
property is false
.
The job of honoring this property, and recognizing a user drag gesture, lies with the look and feel implementation, and in particular, the list's ListUI
. When automatic drag handling is enabled, most look and feels (including those that subclass BasicLookAndFeel
) begin a drag and drop operation whenever the user presses the mouse button over an item and then moves the mouse a few pixels. Setting this property to true
can therefore have a subtle effect on how selections behave.
If a look and feel is used that ignores this property, you can still begin a drag and drop operation by calling exportAsDrag
on the list's TransferHandler
.
- Parameters:
-
b
- whether or not to enable automatic drag handling - Throws:
-
HeadlessException
- ifb
istrue
andGraphicsEnvironment.isHeadless()
returnstrue
- Since:
- 1.4
- See Also:
-
GraphicsEnvironment.isHeadless()
,getDragEnabled()
,JComponent.setTransferHandler(javax.swing.TransferHandler)
,TransferHandler
getDragEnabled
public boolean getDragEnabled()
Returns whether or not automatic drag handling is enabled.
- Returns:
- the value of the
dragEnabled
property - Since:
- 1.4
- See Also:
setDragEnabled(boolean)
setDropMode
public final void setDropMode(DropMode dropMode)
Sets the drop mode for this component. For backward compatibility, the default for this property is DropMode.USE_SELECTION
. Usage of one of the other modes is recommended, however, for an improved user experience. DropMode.ON
, for instance, offers similar behavior of showing items as selected, but does so without affecting the actual selection in the list.
JList
supports the following drop modes:
DropMode.USE_SELECTION
DropMode.ON
DropMode.INSERT
DropMode.ON_OR_INSERT
TransferHandler
that accepts drops.- Parameters:
-
dropMode
- the drop mode to use - Throws:
-
IllegalArgumentException
- if the drop mode is unsupported ornull
- Since:
- 1.6
- See Also:
-
getDropMode()
,getDropLocation()
,JComponent.setTransferHandler(javax.swing.TransferHandler)
,TransferHandler
getDropMode
public final DropMode getDropMode()
Returns the drop mode for this component.
- Returns:
- the drop mode for this component
- Since:
- 1.6
- See Also:
setDropMode(javax.swing.DropMode)
getDropLocation
@BeanProperty(bound=false) public final JList.DropLocation getDropLocation()
Returns the location that this component should visually indicate as the drop location during a DnD operation over the component, or null
if no location is to currently be shown.
This method is not meant for querying the drop location from a TransferHandler
, as the drop location is only set after the TransferHandler
's canImport
has returned and has allowed for the location to be shown.
When this property changes, a property change event with name "dropLocation" is fired by the component.
By default, responsibility for listening for changes to this property and indicating the drop location visually lies with the list's ListUI
, which may paint it directly and/or install a cell renderer to do so. Developers wishing to implement custom drop location painting and/or replace the default cell renderer, may need to honor this property.
- Returns:
- the drop location
- Since:
- 1.6
- See Also:
-
setDropMode(javax.swing.DropMode)
,TransferHandler.canImport(TransferHandler.TransferSupport)
getNextMatch
public int getNextMatch(String prefix, int startIndex, Position.Bias bias)
Returns the next list element whose toString
value starts with the given prefix.
- Parameters:
-
prefix
- the string to test for a match -
startIndex
- the index for starting the search -
bias
- the search direction, either Position.Bias.Forward or Position.Bias.Backward. - Returns:
- the index of the next list element that starts with the prefix; otherwise
-1
- Throws:
-
IllegalArgumentException
- if prefix isnull
or startIndex is out of bounds - Since:
- 1.4
getToolTipText
public String getToolTipText(MouseEvent event)
Returns the tooltip text to be used for the given event. This overrides JComponent
's getToolTipText
to first check the cell renderer component for the cell over which the event occurred, returning its tooltip text, if any. This implementation allows you to specify tooltip text on the cell level, by using setToolTipText
on your cell renderer component.
Note: For JList
to properly display the tooltips of its renderers in this manner, JList
must be a registered component with the ToolTipManager
. This registration is done automatically in the constructor. However, if at a later point JList
is unregistered, by way of a call to setToolTipText(null)
, tips from the renderers will no longer display.
- Overrides:
-
getToolTipText
in classJComponent
- Parameters:
-
event
- theMouseEvent
to fetch the tooltip text for - Returns:
- a string containing the tooltip
- See Also:
-
JComponent.setToolTipText(java.lang.String)
,JComponent.getToolTipText()
locationToIndex
public int locationToIndex(Point location)
Returns the cell index closest to the given location in the list's coordinate system. To determine if the cell actually contains the specified location, compare the point against the cell's bounds, as provided by getCellBounds
. This method returns -1
if the model is empty
This is a cover method that delegates to the method of the same name in the list's ListUI
. It returns -1
if the list has no ListUI
.
- Parameters:
-
location
- the coordinates of the point - Returns:
- the cell index closest to the given location, or
-1
indexToLocation
public Point indexToLocation(int index)
Returns the origin of the specified item in the list's coordinate system. This method returns null
if the index isn't valid.
This is a cover method that delegates to the method of the same name in the list's ListUI
. It returns null
if the list has no ListUI
.
- Parameters:
-
index
- the cell index - Returns:
- the origin of the cell, or
null
getCellBounds
public Rectangle getCellBounds(int index0, int index1)
Returns the bounding rectangle, in the list's coordinate system, for the range of cells specified by the two indices. These indices can be supplied in any order.
If the smaller index is outside the list's range of cells, this method returns null
. If the smaller index is valid, but the larger index is outside the list's range, the bounds of just the first index is returned. Otherwise, the bounds of the valid range is returned.
This is a cover method that delegates to the method of the same name in the list's ListUI
. It returns null
if the list has no ListUI
.
- Parameters:
-
index0
- the first index in the range -
index1
- the second index in the range - Returns:
- the bounding rectangle for the range of cells, or
null
getModel
public ListModel<E> getModel()
Returns the data model that holds the list of items displayed by the JList
component.
- Returns:
- the
ListModel
that provides the displayed list of items - See Also:
setModel(javax.swing.ListModel<E>)
setModel
@BeanProperty(visualUpdate=true, description="The object that contains the data to be drawn by this JList.") public void setModel(ListModel<E> model)
Sets the model that represents the contents or "value" of the list, notifies property change listeners, and then clears the list's selection.
This is a JavaBeans bound property.
- Parameters:
-
model
- theListModel
that provides the list of items for display - Throws:
-
IllegalArgumentException
- ifmodel
isnull
- See Also:
-
getModel()
,clearSelection()
setListData
public void setListData(E[] listData)
Constructs a read-only ListModel
from an array of items, and calls setModel
with this model.
Attempts to pass a null
value to this method results in undefined behavior and, most likely, exceptions. The created model references the given array directly. Attempts to modify the array after invoking this method results in undefined behavior.
- Parameters:
-
listData
- an array ofE
containing the items to display in the list - See Also:
setModel(javax.swing.ListModel<E>)
setListData
public void setListData(Vector<? extends E> listData)
Constructs a read-only ListModel
from a Vector
and calls setModel
with this model.
Attempts to pass a null
value to this method results in undefined behavior and, most likely, exceptions. The created model references the given Vector
directly. Attempts to modify the Vector
after invoking this method results in undefined behavior.
- Parameters:
-
listData
- aVector
containing the items to display in the list - See Also:
setModel(javax.swing.ListModel<E>)
createSelectionModel
protected ListSelectionModel createSelectionModel()
Returns an instance of DefaultListSelectionModel
; called during construction to initialize the list's selection model property.
- Returns:
- a
DefaultListSelecitonModel
, used to initialize the list's selection model property during construction - See Also:
-
setSelectionModel(javax.swing.ListSelectionModel)
,DefaultListSelectionModel
getSelectionModel
public ListSelectionModel getSelectionModel()
Returns the current selection model. The selection model maintains the selection state of the list. See the class level documentation for more details.
- Returns:
- the
ListSelectionModel
that maintains the list's selections - See Also:
-
setSelectionModel(javax.swing.ListSelectionModel)
,ListSelectionModel
fireSelectionValueChanged
protected void fireSelectionValueChanged(int firstIndex, int lastIndex, boolean isAdjusting)
Notifies ListSelectionListener
s added directly to the list of selection changes made to the selection model. JList
listens for changes made to the selection in the selection model, and forwards notification to listeners added to the list directly, by calling this method.
This method constructs a ListSelectionEvent
with this list as the source, and the specified arguments, and sends it to the registered ListSelectionListeners
.
- Parameters:
-
firstIndex
- the first index in the range,<= lastIndex
-
lastIndex
- the last index in the range,>= firstIndex
-
isAdjusting
- whether or not this is one in a series of multiple events, where changes are still being made - See Also:
-
addListSelectionListener(javax.swing.event.ListSelectionListener)
,removeListSelectionListener(javax.swing.event.ListSelectionListener)
,ListSelectionEvent
,EventListenerList
addListSelectionListener
public void addListSelectionListener(ListSelectionListener listener)
Adds a listener to the list, to be notified each time a change to the selection occurs; the preferred way of listening for selection state changes. JList
takes care of listening for selection state changes in the selection model, and notifies the given listener of each change. ListSelectionEvent
s sent to the listener have a source
property set to this list.
- Parameters:
-
listener
- theListSelectionListener
to add - See Also:
-
getSelectionModel()
,getListSelectionListeners()
removeListSelectionListener
public void removeListSelectionListener(ListSelectionListener listener)
Removes a selection listener from the list.
- Parameters:
-
listener
- theListSelectionListener
to remove - See Also:
-
addListSelectionListener(javax.swing.event.ListSelectionListener)
,getSelectionModel()
getListSelectionListeners
@BeanProperty(bound=false) public ListSelectionListener[] getListSelectionListeners()
Returns an array of all the ListSelectionListener
s added to this JList
by way of addListSelectionListener
.
- Returns:
- all of the
ListSelectionListener
s on this list, or an empty array if no listeners have been added - Since:
- 1.4
- See Also:
addListSelectionListener(javax.swing.event.ListSelectionListener)
setSelectionModel
@BeanProperty(description="The selection model, recording which cells are selected.") public void setSelectionModel(ListSelectionModel selectionModel)
Sets the selectionModel
for the list to a non-null
ListSelectionModel
implementation. The selection model handles the task of making single selections, selections of contiguous ranges, and non-contiguous selections.
This is a JavaBeans bound property.
- Parameters:
-
selectionModel
- theListSelectionModel
that implements the selections - Throws:
-
IllegalArgumentException
- ifselectionModel
isnull
- See Also:
getSelectionModel()
setSelectionMode
@BeanProperty(bound=false, enumerationValues={"ListSelectionModel.SINGLE_SELECTION","ListSelectionModel.SINGLE_INTERVAL_SELECTION","ListSelectionModel.MULTIPLE_INTERVAL_SELECTION"}, description="The selection mode.") public void setSelectionMode(int selectionMode)
Sets the selection mode for the list. This is a cover method that sets the selection mode directly on the selection model.
The following list describes the accepted selection modes:
-
ListSelectionModel.SINGLE_SELECTION
- Only one list index can be selected at a time. In this mode,setSelectionInterval
andaddSelectionInterval
are equivalent, both replacing the current selection with the index represented by the second argument (the "lead"). -
ListSelectionModel.SINGLE_INTERVAL_SELECTION
- Only one contiguous interval can be selected at a time. In this mode,addSelectionInterval
behaves likesetSelectionInterval
(replacing the current selection}, unless the given interval is immediately adjacent to or overlaps the existing selection, and can be used to grow the selection. -
ListSelectionModel.MULTIPLE_INTERVAL_SELECTION
- In this mode, there's no restriction on what can be selected. This mode is the default.
- Parameters:
-
selectionMode
- the selection mode - Throws:
-
IllegalArgumentException
- if the selection mode isn't one of those allowed - See Also:
getSelectionMode()
getSelectionMode
public int getSelectionMode()
Returns the current selection mode for the list. This is a cover method that delegates to the method of the same name on the list's selection model.
- Returns:
- the current selection mode
- See Also:
setSelectionMode(int)
getAnchorSelectionIndex
@BeanProperty(bound=false) public int getAnchorSelectionIndex()
Returns the anchor selection index. This is a cover method that delegates to the method of the same name on the list's selection model.
- Returns:
- the anchor selection index
- See Also:
ListSelectionModel.getAnchorSelectionIndex()
getLeadSelectionIndex
@BeanProperty(bound=false, description="The lead selection index.") public int getLeadSelectionIndex()
Returns the lead selection index. This is a cover method that delegates to the method of the same name on the list's selection model.
- Returns:
- the lead selection index
- See Also:
ListSelectionModel.getLeadSelectionIndex()
getMinSelectionIndex
@BeanProperty(bound=false) public int getMinSelectionIndex()
Returns the smallest selected cell index, or -1
if the selection is empty. This is a cover method that delegates to the method of the same name on the list's selection model.
- Returns:
- the smallest selected cell index, or
-1
- See Also:
ListSelectionModel.getMinSelectionIndex()
getMaxSelectionIndex
@BeanProperty(bound=false) public int getMaxSelectionIndex()
Returns the largest selected cell index, or -1
if the selection is empty. This is a cover method that delegates to the method of the same name on the list's selection model.
- Returns:
- the largest selected cell index
- See Also:
ListSelectionModel.getMaxSelectionIndex()
isSelectedIndex
public boolean isSelectedIndex(int index)
Returns true
if the specified index is selected, else false
. This is a cover method that delegates to the method of the same name on the list's selection model.
- Parameters:
-
index
- index to be queried for selection state - Returns:
-
true
if the specified index is selected, elsefalse
- See Also:
-
ListSelectionModel.isSelectedIndex(int)
,setSelectedIndex(int)
isSelectionEmpty
@BeanProperty(bound=false) public boolean isSelectionEmpty()
Returns true
if nothing is selected, else false
. This is a cover method that delegates to the method of the same name on the list's selection model.
- Returns:
-
true
if nothing is selected, elsefalse
- See Also:
-
ListSelectionModel.isSelectionEmpty()
,clearSelection()
clearSelection
public void clearSelection()
Clears the selection; after calling this method, isSelectionEmpty
will return true
. This is a cover method that delegates to the method of the same name on the list's selection model.
setSelectionInterval
public void setSelectionInterval(int anchor, int lead)
Selects the specified interval. Both anchor
and lead
indices are included. anchor
doesn't have to be less than or equal to lead
. This is a cover method that delegates to the method of the same name on the list's selection model.
Refer to the documentation of the selection model class being used for details on how values less than 0
are handled.
- Parameters:
-
anchor
- the first index to select -
lead
- the last index to select - See Also:
-
ListSelectionModel.setSelectionInterval(int, int)
,DefaultListSelectionModel.setSelectionInterval(int, int)
,createSelectionModel()
,addSelectionInterval(int, int)
,removeSelectionInterval(int, int)
addSelectionInterval
public void addSelectionInterval(int anchor, int lead)
Sets the selection to be the union of the specified interval with current selection. Both the anchor
and lead
indices are included. anchor
doesn't have to be less than or equal to lead
. This is a cover method that delegates to the method of the same name on the list's selection model.
Refer to the documentation of the selection model class being used for details on how values less than 0
are handled.
- Parameters:
-
anchor
- the first index to add to the selection -
lead
- the last index to add to the selection - See Also:
-
ListSelectionModel.addSelectionInterval(int, int)
,DefaultListSelectionModel.addSelectionInterval(int, int)
,createSelectionModel()
,setSelectionInterval(int, int)
,removeSelectionInterval(int, int)
removeSelectionInterval
public void removeSelectionInterval(int index0, int index1)
Sets the selection to be the set difference of the specified interval and the current selection. Both the index0
and index1
indices are removed. index0
doesn't have to be less than or equal to index1
. This is a cover method that delegates to the method of the same name on the list's selection model.
Refer to the documentation of the selection model class being used for details on how values less than 0
are handled.
- Parameters:
-
index0
- the first index to remove from the selection -
index1
- the last index to remove from the selection - See Also:
-
ListSelectionModel.removeSelectionInterval(int, int)
,DefaultListSelectionModel.removeSelectionInterval(int, int)
,createSelectionModel()
,setSelectionInterval(int, int)
,addSelectionInterval(int, int)
setValueIsAdjusting
public void setValueIsAdjusting(boolean b)
Sets the selection model's valueIsAdjusting
property. When true
, upcoming changes to selection should be considered part of a single change. This property is used internally and developers typically need not call this method. For example, when the model is being updated in response to a user drag, the value of the property is set to true
when the drag is initiated and set to false
when the drag is finished. This allows listeners to update only when a change has been finalized, rather than handling all of the intermediate values.
You may want to use this directly if making a series of changes that should be considered part of a single change.
This is a cover method that delegates to the method of the same name on the list's selection model. See the documentation for ListSelectionModel.setValueIsAdjusting(boolean)
for more details.
- Parameters:
-
b
- the new value for the property - See Also:
-
ListSelectionModel.setValueIsAdjusting(boolean)
,ListSelectionEvent.getValueIsAdjusting()
,getValueIsAdjusting()
getValueIsAdjusting
public boolean getValueIsAdjusting()
Returns the value of the selection model's isAdjusting
property.
This is a cover method that delegates to the method of the same name on the list's selection model.
- Returns:
- the value of the selection model's
isAdjusting
property. - See Also:
-
setValueIsAdjusting(boolean)
,ListSelectionModel.getValueIsAdjusting()
getSelectedIndices
public int[] getSelectedIndices()
Returns an array of all of the selected indices, in increasing order.
- Returns:
- all of the selected indices, in increasing order, or an empty array if nothing is selected
- See Also:
-
removeSelectionInterval(int, int)
,addListSelectionListener(javax.swing.event.ListSelectionListener)
setSelectedIndex
@BeanProperty(bound=false, description="The index of the selected cell.") public void setSelectedIndex(int index)
Selects a single cell. Does nothing if the given index is greater than or equal to the model size. This is a convenience method that uses setSelectionInterval
on the selection model. Refer to the documentation for the selection model class being used for details on how values less than 0
are handled.
- Parameters:
-
index
- the index of the cell to select - See Also:
-
ListSelectionModel.setSelectionInterval(int, int)
,isSelectedIndex(int)
,addListSelectionListener(javax.swing.event.ListSelectionListener)
setSelectedIndices
public void setSelectedIndices(int[] indices)
Changes the selection to be the set of indices specified by the given array. Indices greater than or equal to the model size are ignored. This is a convenience method that clears the selection and then uses addSelectionInterval
on the selection model to add the indices. Refer to the documentation of the selection model class being used for details on how values less than 0
are handled.
- Parameters:
-
indices
- an array of the indices of the cells to select,non-null
- Throws:
-
NullPointerException
- if the given array isnull
- See Also:
-
ListSelectionModel.addSelectionInterval(int, int)
,isSelectedIndex(int)
,addListSelectionListener(javax.swing.event.ListSelectionListener)
getSelectedValues
@Deprecated @BeanProperty(bound=false) public Object[] getSelectedValues()
getSelectedValuesList()
Returns an array of all the selected values, in increasing order based on their indices in the list.
- Returns:
- the selected values, or an empty array if nothing is selected
- See Also:
-
isSelectedIndex(int)
,getModel()
,addListSelectionListener(javax.swing.event.ListSelectionListener)
getSelectedValuesList
@BeanProperty(bound=false) public List<E> getSelectedValuesList()
Returns a list of all the selected items, in increasing order based on their indices in the list.
- Returns:
- the selected items, or an empty list if nothing is selected
- Since:
- 1.7
- See Also:
-
isSelectedIndex(int)
,getModel()
,addListSelectionListener(javax.swing.event.ListSelectionListener)
getSelectedIndex
public int getSelectedIndex()
Returns the smallest selected cell index; the selection when only a single item is selected in the list. When multiple items are selected, it is simply the smallest selected index. Returns -1
if there is no selection.
This method is a cover that delegates to getMinSelectionIndex
.
- Returns:
- the smallest selected cell index
- See Also:
-
getMinSelectionIndex()
,addListSelectionListener(javax.swing.event.ListSelectionListener)
getSelectedValue
@BeanProperty(bound=false) public E getSelectedValue()
Returns the value for the smallest selected cell index; the selected value when only a single item is selected in the list. When multiple items are selected, it is simply the value for the smallest selected index. Returns null
if there is no selection.
This is a convenience method that simply returns the model value for getMinSelectionIndex
.
- Returns:
- the first selected value
- See Also:
-
getMinSelectionIndex()
,getModel()
,addListSelectionListener(javax.swing.event.ListSelectionListener)
setSelectedValue
public void setSelectedValue(Object anObject, boolean shouldScroll)
Selects the specified object from the list. If the object passed is null
, the selection is cleared.
- Parameters:
-
anObject
- the object to select -
shouldScroll
-true
if the list should scroll to display the selected object, if one exists; otherwisefalse
getPreferredScrollableViewportSize
@BeanProperty(bound=false) public Dimension getPreferredScrollableViewportSize()
Computes the size of viewport needed to display visibleRowCount
rows. The value returned by this method depends on the layout orientation:
VERTICAL
:
This is trivial if both fixedCellWidth
and fixedCellHeight
have been set (either explicitly or by specifying a prototype cell value). The width is simply the fixedCellWidth
plus the list's horizontal insets. The height is the fixedCellHeight
multiplied by the visibleRowCount
, plus the list's vertical insets.
If either fixedCellWidth
or fixedCellHeight
haven't been specified, heuristics are used. If the model is empty, the width is the fixedCellWidth
, if greater than 0
, or a hard-coded value of 256
. The height is the fixedCellHeight
multiplied by visibleRowCount
, if fixedCellHeight
is greater than 0
, otherwise it is a hard-coded value of 16
multiplied by visibleRowCount
.
If the model isn't empty, the width is the preferred size's width, typically the width of the widest list element. The height is the height of the cell with index 0 multiplied by the visibleRowCount
, plus the list's vertical insets.
VERTICAL_WRAP
or HORIZONTAL_WRAP
:
This method simply returns the value from getPreferredSize
. The list's ListUI
is expected to override getPreferredSize
to return an appropriate value.
- Specified by:
-
getPreferredScrollableViewportSize
in interfaceScrollable
- Returns:
- a dimension containing the size of the viewport needed to display
visibleRowCount
rows - See Also:
-
getPreferredScrollableViewportSize()
,setPrototypeCellValue(E)
getScrollableUnitIncrement
public int getScrollableUnitIncrement(Rectangle visibleRect, int orientation, int direction)
Returns the distance to scroll to expose the next or previous row (for vertical scrolling) or column (for horizontal scrolling).
For horizontal scrolling, if the layout orientation is VERTICAL
, then the list's font size is returned (or 1
if the font is null
).
- Specified by:
-
getScrollableUnitIncrement
in interfaceScrollable
- Parameters:
-
visibleRect
- the view area visible within the viewport -
orientation
-SwingConstants.HORIZONTAL
orSwingConstants.VERTICAL
-
direction
- less or equal to zero to scroll up/back, greater than zero for down/forward - Returns:
- the "unit" increment for scrolling in the specified direction; always positive
- Throws:
-
IllegalArgumentException
- ifvisibleRect
isnull
, ororientation
isn't one ofSwingConstants.VERTICAL
orSwingConstants.HORIZONTAL
- See Also:
-
getScrollableBlockIncrement(java.awt.Rectangle, int, int)
,Scrollable.getScrollableUnitIncrement(java.awt.Rectangle, int, int)
getScrollableBlockIncrement
public int getScrollableBlockIncrement(Rectangle visibleRect, int orientation, int direction)
Returns the distance to scroll to expose the next or previous block.
For vertical scrolling, the following rules are used:
- if scrolling down, returns the distance to scroll so that the last visible element becomes the first completely visible element
- if scrolling up, returns the distance to scroll so that the first visible element becomes the last completely visible element
- returns
visibleRect.height
if the list is empty
For horizontal scrolling, when the layout orientation is either VERTICAL_WRAP
or HORIZONTAL_WRAP
:
- if scrolling right, returns the distance to scroll so that the last visible element becomes the first completely visible element
- if scrolling left, returns the distance to scroll so that the first visible element becomes the last completely visible element
- returns
visibleRect.width
if the list is empty
For horizontal scrolling and VERTICAL
orientation, returns visibleRect.width
.
Note that the value of visibleRect
must be the equal to this.getVisibleRect()
.
- Specified by:
-
getScrollableBlockIncrement
in interfaceScrollable
- Parameters:
-
visibleRect
- the view area visible within the viewport -
orientation
-SwingConstants.HORIZONTAL
orSwingConstants.VERTICAL
-
direction
- less or equal to zero to scroll up/back, greater than zero for down/forward - Returns:
- the "block" increment for scrolling in the specified direction; always positive
- Throws:
-
IllegalArgumentException
- ifvisibleRect
isnull
, ororientation
isn't one ofSwingConstants.VERTICAL
orSwingConstants.HORIZONTAL
- See Also:
-
getScrollableUnitIncrement(java.awt.Rectangle, int, int)
,Scrollable.getScrollableBlockIncrement(java.awt.Rectangle, int, int)
getScrollableTracksViewportWidth
@BeanProperty(bound=false) public boolean getScrollableTracksViewportWidth()
Returns true
if this JList
is displayed in a JViewport
and the viewport is wider than the list's preferred width, or if the layout orientation is HORIZONTAL_WRAP
and visibleRowCount <= 0
; otherwise returns false
.
If false
, then don't track the viewport's width. This allows horizontal scrolling if the JViewport
is itself embedded in a JScrollPane
.
- Specified by:
-
getScrollableTracksViewportWidth
in interfaceScrollable
- Returns:
- whether or not an enclosing viewport should force the list's width to match its own
- See Also:
Scrollable.getScrollableTracksViewportWidth()
getScrollableTracksViewportHeight
@BeanProperty(bound=false) public boolean getScrollableTracksViewportHeight()
Returns true
if this JList
is displayed in a JViewport
and the viewport is taller than the list's preferred height, or if the layout orientation is VERTICAL_WRAP
and visibleRowCount <= 0
; otherwise returns false
.
If false
, then don't track the viewport's height. This allows vertical scrolling if the JViewport
is itself embedded in a JScrollPane
.
- Specified by:
-
getScrollableTracksViewportHeight
in interfaceScrollable
- Returns:
- whether or not an enclosing viewport should force the list's height to match its own
- See Also:
Scrollable.getScrollableTracksViewportHeight()
paramString
protected String paramString()
Returns a String
representation of this JList
. This method is intended to be used only for debugging purposes, and the content and format of the returned String
may vary between implementations. The returned String
may be empty, but may not be null
.
- Overrides:
-
paramString
in classJComponent
- Returns:
- a
String
representation of thisJList
.
getAccessibleContext
@BeanProperty(bound=false) public AccessibleContext getAccessibleContext()
Gets the AccessibleContext
associated with this JList
. For JList
, the AccessibleContext
takes the form of an AccessibleJList
.
A new AccessibleJList
instance is created if necessary.
- Specified by:
-
getAccessibleContext
in interfaceAccessible
- Overrides:
-
getAccessibleContext
in classComponent
- Returns:
- an
AccessibleJList
that serves as theAccessibleContext
of thisJList