W3cubDocs

Class BasicTreeUI

java.lang.Object

javax.swing.plaf.ComponentUI

javax.swing.plaf.TreeUI

javax.swing.plaf.basic.BasicTreeUI

Direct Known Subclasses:: MetalTreeUI, SynthTreeUI

public class BasicTreeUI extends TreeUI

The basic L&F for a hierarchical data structure.

Nested Class Summary

Modifier and Type	Class	Description
`class`	`BasicTreeUI.CellEditorHandler`	Listener responsible for getting cell editing events and updating the tree accordingly.
`class`	`BasicTreeUI.ComponentHandler`	Updates the preferred size when scrolling (if necessary).
`class`	`BasicTreeUI.FocusHandler`	Repaints the lead selection row when focus is lost/gained.
`class`	`BasicTreeUI.KeyHandler`	This is used to get multiple key down events to appropriately generate events.
`class`	`BasicTreeUI.MouseHandler`	TreeMouseListener is responsible for updating the selection based on mouse events.
`class`	`BasicTreeUI.MouseInputHandler`	MouseInputHandler handles passing all mouse events, including mouse motion events, until the mouse is released to the destination it is constructed with.
`class`	`BasicTreeUI.NodeDimensionsHandler`	Class responsible for getting size of node, method is forwarded to BasicTreeUI method.
`class`	`BasicTreeUI.PropertyChangeHandler`	PropertyChangeListener for the tree.
`class`	`BasicTreeUI.SelectionModelPropertyChangeHandler`	Listener on the TreeSelectionModel, resets the row selection if any of the properties of the model change.
`class`	`BasicTreeUI.TreeCancelEditingAction`	ActionListener that invokes cancelEditing when action performed.
`class`	`BasicTreeUI.TreeExpansionHandler`	Updates the TreeState in response to nodes expanding/collapsing.
`class`	`BasicTreeUI.TreeHomeAction`	TreeHomeAction is used to handle end/home actions.
`class`	`BasicTreeUI.TreeIncrementAction`	TreeIncrementAction is used to handle up/down actions.
`class`	`BasicTreeUI.TreeModelHandler`	Forwards all TreeModel events to the TreeState.
`class`	`BasicTreeUI.TreePageAction`	TreePageAction handles page up and page down events.
`class`	`BasicTreeUI.TreeSelectionHandler`	Listens for changes in the selection model and updates the display accordingly.
`class`	`BasicTreeUI.TreeToggleAction`	For the first selected row expandedness will be toggled.
`class`	`BasicTreeUI.TreeTraverseAction`	`TreeTraverseAction` is the action used for left/right keys.

Field Summary

Modifier and Type	Field	Description
`protected TreeCellEditor`	`cellEditor`	Editor for the tree.
`protected Icon`	`collapsedIcon`	The collapsed icon.
`protected boolean`	`createdCellEditor`	Set to true if editor that is currently in the tree was created by this instance.
`protected boolean`	`createdRenderer`	Set to true if the renderer that is currently in the tree was created by this instance.
`protected TreeCellRenderer`	`currentCellRenderer`	Renderer that is being used to do the actual cell drawing.
`protected int`	`depthOffset`	How much the depth should be offset to properly calculate x locations.
`protected Hashtable<TreePath,Boolean>`	`drawingCache`	Used for minimizing the drawing of vertical lines.
`protected Component`	`editingComponent`	When editing, this will be the Component that is doing the actual editing.
`protected TreePath`	`editingPath`	Path that is being edited.
`protected int`	`editingRow`	Row that is being edited.
`protected boolean`	`editorHasDifferentSize`	Set to true if the editor has a different size than the renderer.
`protected Icon`	`expandedIcon`	The expanded icon.
`protected boolean`	`largeModel`	True if doing optimizations for a largeModel.
`protected int`	`lastSelectedRow`	Index of the row that was last selected.
`protected int`	`leftChildIndent`	Distance between left margin and where vertical dashes will be drawn.
`protected AbstractLayoutCache.NodeDimensions`	`nodeDimensions`	Responsible for telling the TreeState the size needed for a node.
`protected Dimension`	`preferredMinSize`	Minimum preferred size.
`protected Dimension`	`preferredSize`	Size needed to completely display all the nodes.
`protected CellRendererPane`	`rendererPane`	Used to paint the TreeCellRenderer.
`protected int`	`rightChildIndent`	Distance to add to leftChildIndent to determine where cell contents will be drawn.
`protected boolean`	`stopEditingInCompleteEditing`	Set to false when editing and shouldSelectCell() returns true meaning the node should be selected before editing, used in completeEditing.
`protected int`	`totalChildIndent`	Total distance that will be indented.
`protected JTree`	`tree`	Component that we're going to be drawing into.
`protected TreeModel`	`treeModel`	Used to determine what to display.
`protected TreeSelectionModel`	`treeSelectionModel`	Model maintaining the selection.
`protected AbstractLayoutCache`	`treeState`	Object responsible for handling sizing and expanded issues.
`protected boolean`	`validCachedPreferredSize`	Is the preferredSize valid?

Constructor Summary

Constructor	Description
`BasicTreeUI()`	Constructs a new instance of `BasicTreeUI`.

Method Summary

Modifier and Type	Method	Description
`void`	`cancelEditing(JTree tree)`	Cancels the current editing session.
`protected void`	`checkForClickInExpandControl(TreePath path, int mouseX, int mouseY)`	If the `mouseX` and `mouseY` are in the expand/collapse region of the `row`, this will toggle the row.
`protected void`	`completeEditing()`	Messages to stop the editing session.
`protected void`	`completeEditing(boolean messageStop, boolean messageCancel, boolean messageTree)`	Stops the editing session.
`protected void`	`completeUIInstall()`	Invoked from installUI after all the defaults/listeners have been installed.
`protected void`	`completeUIUninstall()`	Uninstalls UI.
`protected void`	`configureLayoutCache()`	Resets the TreeState instance based on the tree we're providing the look and feel for.
`protected CellEditorListener`	`createCellEditorListener()`	Creates a listener to handle events from the current editor.
`protected CellRendererPane`	`createCellRendererPane()`	Returns the renderer pane that renderer components are placed in.
`protected ComponentListener`	`createComponentListener()`	Creates and returns a new ComponentHandler.
`protected TreeCellEditor`	`createDefaultCellEditor()`	Creates a default cell editor.
`protected TreeCellRenderer`	`createDefaultCellRenderer()`	Returns the default cell renderer that is used to do the stamping of each node.
`protected FocusListener`	`createFocusListener()`	Creates a listener that is responsible for updating the display when focus is lost/gained.
`protected KeyListener`	`createKeyListener()`	Creates the listener responsible for getting key events from the tree.
`protected AbstractLayoutCache`	`createLayoutCache()`	Creates the object responsible for managing what is expanded, as well as the size of nodes.
`protected MouseListener`	`createMouseListener()`	Creates the listener responsible for updating the selection based on mouse events.
`protected AbstractLayoutCache.NodeDimensions`	`createNodeDimensions()`	Creates an instance of `NodeDimensions` that is able to determine the size of a given node in the tree.
`protected PropertyChangeListener`	`createPropertyChangeListener()`	Creates a listener that is responsible that updates the UI based on how the tree changes.
`protected PropertyChangeListener`	`createSelectionModelPropertyChangeListener()`	Creates the listener responsible for getting property change events from the selection model.
`protected TreeExpansionListener`	`createTreeExpansionListener()`	Creates and returns the object responsible for updating the treestate when nodes expanded state changes.
`protected TreeModelListener`	`createTreeModelListener()`	Returns a listener that can update the tree when the model changes.
`protected TreeSelectionListener`	`createTreeSelectionListener()`	Creates the listener that updates the display based on selection change methods.
`static ComponentUI`	`createUI(JComponent x)`	Constructs a new instance of `BasicTreeUI`.
`protected void`	`drawCentered(Component c, Graphics graphics, Icon icon, int x, int y)`	Draws the `icon` centered at (x,y).
`protected void`	`drawDashedHorizontalLine(Graphics g, int y, int x1, int x2)`	Draws a horizontal dashed line.
`protected void`	`drawDashedVerticalLine(Graphics g, int x, int y1, int y2)`	Draws a vertical dashed line.
`protected void`	`ensureRowsAreVisible(int beginRow, int endRow)`	Ensures that the rows identified by `beginRow` through `endRow` are visible.
`int`	`getBaseline(JComponent c, int width, int height)`	Returns the baseline.
`Component.BaselineResizeBehavior`	`getBaselineResizeBehavior(JComponent c)`	Returns an enum indicating how the baseline of the component changes as the size changes.
`protected TreeCellEditor`	`getCellEditor()`	Returns the editor used to edit entries in the drawn tree component, or `null` if the tree cannot be edited.
`protected TreeCellRenderer`	`getCellRenderer()`	Returns the current instance of the `TreeCellRenderer` that is rendering each cell.
`TreePath`	`getClosestPathForLocation(JTree tree, int x, int y)`	Returns the path to the node that is closest to x,y.
`Icon`	`getCollapsedIcon()`	Returns the collapsed icon.
`protected Rectangle`	`getDropLineRect(JTree.DropLocation loc)`	Returns a unbounding box for the drop line.
`TreePath`	`getEditingPath(JTree tree)`	Returns the path to the element that is being edited.
`Icon`	`getExpandedIcon()`	Returns the expanded icon.
`protected Color`	`getHashColor()`	Returns the hash color.
`protected int`	`getHorizontalLegBuffer()`	The horizontal element of legs between nodes starts at the right of the left-hand side of the child node by default.
`protected TreePath`	`getLastChildPath(TreePath parent)`	Returns a path to the last child of `parent`.
`protected int`	`getLeadSelectionRow()`	Returns the lead row of the selection.
`int`	`getLeftChildIndent()`	Returns the left child indent.
`Dimension`	`getMaximumSize(JComponent c)`	Returns the maximum size for this component, which will be the preferred size if the instance is currently in a JTree, or 0, 0.
`Dimension`	`getMinimumSize(JComponent c)`	Returns the minimum size for this component.
`protected TreeModel`	`getModel()`	Returns the tree model.
`Rectangle`	`getPathBounds(JTree tree, TreePath path)`	Returns the Rectangle enclosing the label portion that the last item in path will be drawn into.
`TreePath`	`getPathForRow(JTree tree, int row)`	Returns the path for passed in row.
`Dimension`	`getPreferredMinSize()`	Returns the minimum preferred size.
`Dimension`	`getPreferredSize(JComponent c)`	Returns the preferred size to properly display the tree, this is a cover method for `getPreferredSize(c, true)`.
`Dimension`	`getPreferredSize(JComponent c, boolean checkConsistency)`	Returns the preferred size to represent the tree in c.
`int`	`getRightChildIndent()`	Returns the right child indent.
`int`	`getRowCount(JTree tree)`	Returns the number of rows that are being displayed.
`int`	`getRowForPath(JTree tree, TreePath path)`	Returns the row that the last item identified in path is visible at.
`protected int`	`getRowHeight()`	Returns the height of each row in the drawn tree component.
`protected int`	`getRowX(int row, int depth)`	Returns the location, along the x-axis, to render a particular row at.
`protected TreeSelectionModel`	`getSelectionModel()`	Returns the current instance of the `TreeSelectionModel` which is the model for selections.
`protected boolean`	`getShowsRootHandles()`	Returns `true` if the root handles are to be displayed.
`protected int`	`getVerticalLegBuffer()`	The vertical element of legs between nodes starts at the bottom of the parent node by default.
`protected void`	`handleExpandControlClick(TreePath path, int mouseX, int mouseY)`	Messaged when the user clicks the particular row, this invokes `toggleExpandState`.
`protected void`	`installComponents()`	Intalls the subcomponents of the tree, which is the renderer pane.
`protected void`	`installDefaults()`	Installs default properties.
`protected void`	`installKeyboardActions()`	Registers keyboard actions.
`protected void`	`installListeners()`	Registers listeners.
`protected boolean`	`isDropLine(JTree.DropLocation loc)`	Tells if a `DropLocation` should be indicated by a line between nodes.
`protected boolean`	`isEditable()`	Returns whether the drawn tree component should be enabled for editing.
`boolean`	`isEditing(JTree tree)`	Returns true if the tree is being edited.
`protected boolean`	`isLargeModel()`	Returns `true` if large model is set.
`protected boolean`	`isLeaf(int row)`	Returns `true` if the node at `row` is a leaf.
`protected boolean`	`isLocationInExpandControl(TreePath path, int mouseX, int mouseY)`	Returns `true` if `mouseX` and `mouseY` fall in the area of row that is used to expand/collapse the node and the node at `row` does not represent a leaf.
`protected boolean`	`isMultiSelectEvent(MouseEvent event)`	Returning `true` signifies a mouse event on the node should select from the anchor point.
`protected boolean`	`isRootVisible()`	Returns whether the root node of the drawn tree component should be displayed.
`protected boolean`	`isToggleEvent(MouseEvent event)`	Returning `true` indicates the row under the mouse should be toggled based on the event.
`protected boolean`	`isToggleSelectionEvent(MouseEvent event)`	Returning `true` signifies a mouse event on the node should toggle the selection of only the row under mouse.
`protected void`	`paintDropLine(Graphics g)`	Paints the drop line.
`protected void`	`paintExpandControl(Graphics g, Rectangle clipBounds, Insets insets, Rectangle bounds, TreePath path, int row, boolean isExpanded, boolean hasBeenExpanded, boolean isLeaf)`	Paints the expand (toggle) part of a row.
`protected void`	`paintHorizontalLine(Graphics g, JComponent c, int y, int left, int right)`	Paints a horizontal line.
`protected void`	`paintHorizontalPartOfLeg(Graphics g, Rectangle clipBounds, Insets insets, Rectangle bounds, TreePath path, int row, boolean isExpanded, boolean hasBeenExpanded, boolean isLeaf)`	Paints the horizontal part of the leg.
`protected void`	`paintRow(Graphics g, Rectangle clipBounds, Insets insets, Rectangle bounds, TreePath path, int row, boolean isExpanded, boolean hasBeenExpanded, boolean isLeaf)`	Paints the renderer part of a row.
`protected void`	`paintVerticalLine(Graphics g, JComponent c, int x, int top, int bottom)`	Paints a vertical line.
`protected void`	`paintVerticalPartOfLeg(Graphics g, Rectangle clipBounds, Insets insets, TreePath path)`	Paints the vertical part of the leg.
`protected void`	`pathWasCollapsed(TreePath path)`	Messaged from the `VisibleTreeNode` after it has collapsed.
`protected void`	`pathWasExpanded(TreePath path)`	Messaged from the `VisibleTreeNode` after it has been expanded.
`protected void`	`prepareForUIInstall()`	Invoked after the `tree` instance variable has been set, but before any defaults/listeners have been installed.
`protected void`	`prepareForUIUninstall()`	Invoked before uninstallation of UI.
`protected void`	`selectPathForEvent(TreePath path, MouseEvent event)`	Messaged to update the selection based on a `MouseEvent` over a particular row.
`protected void`	`setCellEditor(TreeCellEditor editor)`	Sets the cell editor.
`protected void`	`setCellRenderer(TreeCellRenderer tcr)`	Sets the `TreeCellRenderer` to `tcr`.
`void`	`setCollapsedIcon(Icon newG)`	Sets the collapsed icon.
`protected void`	`setEditable(boolean newValue)`	Configures the receiver to allow, or not allow, editing.
`void`	`setExpandedIcon(Icon newG)`	Sets the expanded icon.
`protected void`	`setHashColor(Color color)`	Sets the hash color.
`protected void`	`setLargeModel(boolean largeModel)`	Sets the `largeModel`.
`void`	`setLeftChildIndent(int newAmount)`	Sets the left child indent.
`protected void`	`setModel(TreeModel model)`	Sets the `TreeModel`.
`void`	`setPreferredMinSize(Dimension newSize)`	Sets the preferred minimum size.
`void`	`setRightChildIndent(int newAmount)`	Sets the right child indent.
`protected void`	`setRootVisible(boolean newValue)`	Sets the root to being visible.
`protected void`	`setRowHeight(int rowHeight)`	Sets the row height, this is forwarded to the treeState.
`protected void`	`setSelectionModel(TreeSelectionModel newLSM)`	Resets the selection model.
`protected void`	`setShowsRootHandles(boolean newValue)`	Determines whether the node handles are to be displayed.
`protected boolean`	`shouldPaintExpandControl(TreePath path, int row, boolean isExpanded, boolean hasBeenExpanded, boolean isLeaf)`	Returns `true` if the expand (toggle) control should be drawn for the specified row.
`protected boolean`	`startEditing(TreePath path, MouseEvent event)`	Will start editing for node if there is a `cellEditor` and `shouldSelectCell` returns `true`.
`void`	`startEditingAtPath(JTree tree, TreePath path)`	Selects the last item in path and tries to edit it.
`boolean`	`stopEditing(JTree tree)`	Stops the current editing session.
`protected void`	`toggleExpandState(TreePath path)`	Expands path if it is not expanded, or collapses row if it is expanded.
`protected void`	`uninstallComponents()`	Uninstalls the renderer pane.
`protected void`	`uninstallDefaults()`	Uninstalls default properties.
`protected void`	`uninstallKeyboardActions()`	Unregisters keyboard actions.
`protected void`	`uninstallListeners()`	Unregisters listeners.
`protected void`	`updateCachedPreferredSize()`	Updates the `preferredSize` instance variable, which is returned from `getPreferredSize()`.
`protected void`	`updateCellEditor()`	Updates the cellEditor based on the editability of the JTree that we're contained in.
`protected void`	`updateDepthOffset()`	Updates how much each depth should be offset by.
`protected void`	`updateExpandedDescendants(TreePath path)`	Updates the expanded state of all the descendants of `path` by getting the expanded descendants from the tree and forwarding to the tree state.
`protected void`	`updateLayoutCacheExpandedNodes()`	Makes all the nodes that are expanded in JTree expanded in LayoutCache.
`protected void`	`updateLeadSelectionRow()`	Updates the lead row of the selection.
`protected void`	`updateRenderer()`	Messaged from the tree we're in when the renderer has changed.
`protected void`	`updateSize()`	Marks the cached size as being invalid, and messages the tree with `treeDidChange`.

Methods declared in class javax.swing.plaf.ComponentUI

contains, getAccessibleChild, getAccessibleChildrenCount, installUI, paint, uninstallUI, update

Methods declared in class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

collapsedIcon

protected transient Icon collapsedIcon

The collapsed icon.

expandedIcon

protected transient Icon expandedIcon

The expanded icon.

leftChildIndent

protected int leftChildIndent

Distance between left margin and where vertical dashes will be drawn.

rightChildIndent

protected int rightChildIndent

Distance to add to leftChildIndent to determine where cell contents will be drawn.

totalChildIndent

protected int totalChildIndent

Total distance that will be indented. The sum of leftChildIndent and rightChildIndent.

preferredMinSize

protected Dimension preferredMinSize

Minimum preferred size.

lastSelectedRow

protected int lastSelectedRow

Index of the row that was last selected.

tree

protected JTree tree

Component that we're going to be drawing into.

currentCellRenderer

protected transient TreeCellRenderer currentCellRenderer

Renderer that is being used to do the actual cell drawing.

createdRenderer

protected boolean createdRenderer

Set to true if the renderer that is currently in the tree was created by this instance.

cellEditor

protected transient TreeCellEditor cellEditor

Editor for the tree.

createdCellEditor

protected boolean createdCellEditor

Set to true if editor that is currently in the tree was created by this instance.

stopEditingInCompleteEditing

protected boolean stopEditingInCompleteEditing

Set to false when editing and shouldSelectCell() returns true meaning the node should be selected before editing, used in completeEditing.

rendererPane

protected CellRendererPane rendererPane

Used to paint the TreeCellRenderer.

preferredSize

protected Dimension preferredSize

Size needed to completely display all the nodes.

validCachedPreferredSize

protected boolean validCachedPreferredSize

Is the preferredSize valid?

treeState

protected AbstractLayoutCache treeState

Object responsible for handling sizing and expanded issues.

drawingCache

protected Hashtable<TreePath,Boolean> drawingCache

Used for minimizing the drawing of vertical lines.

largeModel

protected boolean largeModel

True if doing optimizations for a largeModel. Subclasses that don't support this may wish to override createLayoutCache to not return a FixedHeightLayoutCache instance.

nodeDimensions

protected AbstractLayoutCache.NodeDimensions nodeDimensions

Responsible for telling the TreeState the size needed for a node.

treeModel

protected TreeModel treeModel

Used to determine what to display.

treeSelectionModel

protected TreeSelectionModel treeSelectionModel

Model maintaining the selection.

depthOffset

protected int depthOffset

How much the depth should be offset to properly calculate x locations. This is based on whether or not the root is visible, and if the root handles are visible.

editingComponent

protected Component editingComponent

When editing, this will be the Component that is doing the actual editing.

editingPath

protected TreePath editingPath

Path that is being edited.

editingRow

protected int editingRow

Row that is being edited. Should only be referenced if editingComponent is not null.

editorHasDifferentSize

protected boolean editorHasDifferentSize

Set to true if the editor has a different size than the renderer.

Constructor Details

BasicTreeUI

public BasicTreeUI()

Constructs a new instance of BasicTreeUI.

Method Details

createUI

public static ComponentUI createUI(JComponent x)

Constructs a new instance of BasicTreeUI.

Parameters:: x - a component
Returns:: a new instance of BasicTreeUI

getHashColor

protected Color getHashColor()

Returns the hash color.

Returns:: the hash color

setHashColor

protected void setHashColor(Color color)

Sets the hash color.

Parameters:: color - the hash color

setLeftChildIndent

public void setLeftChildIndent(int newAmount)

Sets the left child indent.

Parameters:: newAmount - the left child indent

getLeftChildIndent

public int getLeftChildIndent()

Returns the left child indent.

Returns:: the left child indent

setRightChildIndent

public void setRightChildIndent(int newAmount)

Sets the right child indent.

Parameters:: newAmount - the right child indent

getRightChildIndent

public int getRightChildIndent()

Returns the right child indent.

Returns:: the right child indent

setExpandedIcon

public void setExpandedIcon(Icon newG)

Sets the expanded icon.

Parameters:: newG - the expanded icon

getExpandedIcon

public Icon getExpandedIcon()

Returns the expanded icon.

Returns:: the expanded icon

setCollapsedIcon

public void setCollapsedIcon(Icon newG)

Sets the collapsed icon.

Parameters:: newG - the collapsed icon

getCollapsedIcon

public Icon getCollapsedIcon()

Returns the collapsed icon.

Returns:: the collapsed icon

setLargeModel

protected void setLargeModel(boolean largeModel)

Sets the largeModel. Called when the largeModel property is changed in the drawn tree component.

Parameters:: largeModel - the new value of the largeModel property

isLargeModel

protected boolean isLargeModel()

Returns true if large model is set.

Returns:: true if large model is set

setRowHeight

protected void setRowHeight(int rowHeight)

Sets the row height, this is forwarded to the treeState. Called when the rowHeight property is changed in the drawn tree component.

Parameters:: rowHeight - the new value of the rowHeight property

getRowHeight

protected int getRowHeight()

Returns the height of each row in the drawn tree component. If the returned value is less than or equal to 0 the height for each row is determined by the renderer.

Returns:: the height of each row, in pixels

setCellRenderer

protected void setCellRenderer(TreeCellRenderer tcr)

Sets the TreeCellRenderer to tcr. This invokes updateRenderer. Called when the cellRenderer property is changed in the drawn tree component.

Parameters:: tcr - the new value of the cellRenderer property

getCellRenderer

protected TreeCellRenderer getCellRenderer()

Returns the current instance of the TreeCellRenderer that is rendering each cell.

Returns:: the TreeCellRenderer instance

setModel

protected void setModel(TreeModel model)

Sets the TreeModel.

Parameters:: model - the new value

getModel

protected TreeModel getModel()

Returns the tree model.

Returns:: the tree model

setRootVisible

protected void setRootVisible(boolean newValue)

Sets the root to being visible. Called when the rootVisible property is changed in the drawn tree component.

Parameters:: newValue - the new value of the rootVisible property

isRootVisible

protected boolean isRootVisible()

Returns whether the root node of the drawn tree component should be displayed.

Returns:: true if the root node of the tree is displayed

setShowsRootHandles

protected void setShowsRootHandles(boolean newValue)

Determines whether the node handles are to be displayed. Called when the showsRootHandles property is changed in the drawn tree component.

Parameters:: newValue - the new value of the showsRootHandles property

getShowsRootHandles

protected boolean getShowsRootHandles()

Returns true if the root handles are to be displayed.

Returns:: true if the root handles are to be displayed

setCellEditor

protected void setCellEditor(TreeCellEditor editor)

Sets the cell editor. Called when the cellEditor property is changed in the drawn tree component.

Parameters:: editor - the new value of the cellEditor property

getCellEditor

protected TreeCellEditor getCellEditor()

Returns the editor used to edit entries in the drawn tree component, or null if the tree cannot be edited.

Returns:: the TreeCellEditor instance, or null

setEditable

protected void setEditable(boolean newValue)

Configures the receiver to allow, or not allow, editing. Called when the editable property is changed in the drawn tree component.

Parameters:: newValue - the new value of the editable property

isEditable

protected boolean isEditable()

Returns whether the drawn tree component should be enabled for editing.

Returns:: true if the tree is editable

setSelectionModel

protected void setSelectionModel(TreeSelectionModel newLSM)

Resets the selection model. The appropriate listener are installed on the model. Called when the selectionModel property is changed in the drawn tree component.

Parameters:: newLSM - the new value of the selectionModel property

getSelectionModel

protected TreeSelectionModel getSelectionModel()

Returns the current instance of the TreeSelectionModel which is the model for selections.

Returns:: the TreeSelectionModel instance

getPathBounds

public Rectangle getPathBounds(JTree tree, TreePath path)

Returns the Rectangle enclosing the label portion that the last item in path will be drawn into. Will return null if any component in path is currently invalid.

Specified by:: getPathBounds in class TreeUI
Parameters:: tree - the JTree for path; path - the TreePath identifying the node
Returns:: the Rectangle enclosing the label portion that the last item in path will be drawn into, null if any component in path is currently valid.

getPathForRow

public TreePath getPathForRow(JTree tree, int row)

Returns the path for passed in row. If row is not visible null is returned.

Specified by:: getPathForRow in class TreeUI
Parameters:: tree - a JTree object; row - an integer specifying a row
Returns:: the path for row or null if row is not visible

getRowForPath

public int getRowForPath(JTree tree, TreePath path)

Returns the row that the last item identified in path is visible at. Will return -1 if any of the elements in path are not currently visible.

Specified by:: getRowForPath in class TreeUI
Parameters:: tree - the JTree for path; path - the TreePath object to look in
Returns:: an integer specifying the row at which the last item identified is visible, -1 if any of the elements in path are not currently visible

getRowCount

public int getRowCount(JTree tree)

Returns the number of rows that are being displayed.

Specified by:: getRowCount in class TreeUI
Parameters:: tree - the JTree for which to count rows
Returns:: an integer specifying the number of row being displayed

getClosestPathForLocation

public TreePath getClosestPathForLocation(JTree tree, int x, int y)

Returns the path to the node that is closest to x,y. If there is nothing currently visible this will return null, otherwise it'll always return a valid path. If you need to test if the returned object is exactly at x, y you should get the bounds for the returned path and test x, y against that.

Specified by:: getClosestPathForLocation in class TreeUI
Parameters:: tree - a JTree object; x - an integer giving the number of pixels horizontally from the left edge of the display area; y - an integer giving the number of pixels vertically from the top of the display area, minus any top margin
Returns:: the TreePath node closest to x,y or null if there is nothing currently visible

isEditing

public boolean isEditing(JTree tree)

Returns true if the tree is being edited. The item that is being edited can be returned by getEditingPath().

Specified by:: isEditing in class TreeUI
Parameters:: tree - a JTree object
Returns:: true if tree is being edited

stopEditing

public boolean stopEditing(JTree tree)

Stops the current editing session. This has no effect if the tree isn't being edited. Returns true if the editor allows the editing session to stop.

Specified by:: stopEditing in class TreeUI
Parameters:: tree - a JTree object
Returns:: true if the editor allows the editing session to stop

cancelEditing

public void cancelEditing(JTree tree)

Cancels the current editing session.

Specified by:: cancelEditing in class TreeUI
Parameters:: tree - a JTree object

startEditingAtPath

public void startEditingAtPath(JTree tree, TreePath path)

Selects the last item in path and tries to edit it. Editing will fail if the CellEditor won't allow it for the selected item.

Specified by:: startEditingAtPath in class TreeUI
Parameters:: tree - the JTree being edited; path - the TreePath to be edited

getEditingPath

public TreePath getEditingPath(JTree tree)

Returns the path to the element that is being edited.

Specified by:: getEditingPath in class TreeUI
Parameters:: tree - the JTree for which to return a path
Returns:: a TreePath containing the path to tree

prepareForUIInstall

protected void prepareForUIInstall()

Invoked after the tree instance variable has been set, but before any defaults/listeners have been installed.

completeUIInstall

protected void completeUIInstall()

Invoked from installUI after all the defaults/listeners have been installed.

installDefaults

protected void installDefaults()

Installs default properties.

installListeners

protected void installListeners()

Registers listeners.

installKeyboardActions

protected void installKeyboardActions()

Registers keyboard actions.

installComponents

protected void installComponents()

Intalls the subcomponents of the tree, which is the renderer pane.

createNodeDimensions

protected AbstractLayoutCache.NodeDimensions createNodeDimensions()

Creates an instance of NodeDimensions that is able to determine the size of a given node in the tree.

Returns:: an instance of NodeDimensions

createPropertyChangeListener

protected PropertyChangeListener createPropertyChangeListener()

Creates a listener that is responsible that updates the UI based on how the tree changes.

Returns:: an instance of the PropertyChangeListener

createMouseListener

protected MouseListener createMouseListener()

Creates the listener responsible for updating the selection based on mouse events.

Returns:: an instance of the MouseListener

createFocusListener

protected FocusListener createFocusListener()

Creates a listener that is responsible for updating the display when focus is lost/gained.

Returns:: an instance of the FocusListener

createKeyListener

protected KeyListener createKeyListener()

Creates the listener responsible for getting key events from the tree.

Returns:: an instance of the KeyListener

createSelectionModelPropertyChangeListener

protected PropertyChangeListener createSelectionModelPropertyChangeListener()

Creates the listener responsible for getting property change events from the selection model.

Returns:: an instance of the PropertyChangeListener

createTreeSelectionListener

protected TreeSelectionListener createTreeSelectionListener()

Creates the listener that updates the display based on selection change methods.

Returns:: an instance of the TreeSelectionListener

createCellEditorListener

protected CellEditorListener createCellEditorListener()

Creates a listener to handle events from the current editor.

Returns:: an instance of the CellEditorListener

createComponentListener

protected ComponentListener createComponentListener()

Creates and returns a new ComponentHandler. This is used for the large model to mark the validCachedPreferredSize as invalid when the component moves.

Returns:: an instance of the ComponentListener

createTreeExpansionListener

protected TreeExpansionListener createTreeExpansionListener()

Creates and returns the object responsible for updating the treestate when nodes expanded state changes.

Returns:: an instance of the TreeExpansionListener

createLayoutCache

protected AbstractLayoutCache createLayoutCache()

Creates the object responsible for managing what is expanded, as well as the size of nodes.

Returns:: the object responsible for managing what is expanded

createCellRendererPane

protected CellRendererPane createCellRendererPane()

Returns the renderer pane that renderer components are placed in.

Returns:: an instance of the CellRendererPane

createDefaultCellEditor

protected TreeCellEditor createDefaultCellEditor()

Creates a default cell editor.

Returns:: a default cell editor

createDefaultCellRenderer

protected TreeCellRenderer createDefaultCellRenderer()

Returns the default cell renderer that is used to do the stamping of each node.

Returns:: an instance of TreeCellRenderer

createTreeModelListener

protected TreeModelListener createTreeModelListener()

Returns a listener that can update the tree when the model changes.

Returns:: an instance of the TreeModelListener.

prepareForUIUninstall

protected void prepareForUIUninstall()

Invoked before uninstallation of UI.

completeUIUninstall

protected void completeUIUninstall()

Uninstalls UI.

uninstallDefaults

protected void uninstallDefaults()

Uninstalls default properties.

uninstallListeners

protected void uninstallListeners()

Unregisters listeners.

uninstallKeyboardActions

protected void uninstallKeyboardActions()

Unregisters keyboard actions.

uninstallComponents

protected void uninstallComponents()

Uninstalls the renderer pane.

getBaseline

public int getBaseline(JComponent c, int width, int height)

Returns the baseline.

Overrides:

getBaseline in class ComponentUI

Parameters:

c - JComponent baseline is being requested for

width - the width to get the baseline for

height - the height to get the baseline for

Returns:

baseline or a value < 0 indicating there is no reasonable baseline

Throws:

NullPointerException - if c is null

IllegalArgumentException - if width or height is < 0

Since:

1.6

See Also:

getBaselineResizeBehavior

public Component.BaselineResizeBehavior getBaselineResizeBehavior(JComponent c)

Returns an enum indicating how the baseline of the component changes as the size changes.

Overrides:

getBaselineResizeBehavior in class ComponentUI

Parameters:

c - JComponent to return baseline resize behavior for

Returns:

an enum indicating how the baseline changes as the component size changes

Throws:

NullPointerException - if c is null

Since:

1.6

See Also:

isDropLine

protected boolean isDropLine(JTree.DropLocation loc)

Tells if a DropLocation should be indicated by a line between nodes. This is meant for javax.swing.DropMode.INSERT and javax.swing.DropMode.ON_OR_INSERT drop modes.

Parameters:: loc - a DropLocation
Returns:: true if the drop location should be shown as a line
Since:: 1.7

paintDropLine

protected void paintDropLine(Graphics g)

Paints the drop line.

Parameters:: g - Graphics object to draw on
Since:: 1.7

getDropLineRect

protected Rectangle getDropLineRect(JTree.DropLocation loc)

Returns a unbounding box for the drop line.

Parameters:: loc - a DropLocation
Returns:: bounding box for the drop line
Since:: 1.7

paintHorizontalPartOfLeg

protected void paintHorizontalPartOfLeg(Graphics g, Rectangle clipBounds, Insets insets, Rectangle bounds, TreePath path, int row, boolean isExpanded, boolean hasBeenExpanded, boolean isLeaf)

Paints the horizontal part of the leg. The receiver should NOT modify clipBounds, or insets.

NOTE: parentRow can be -1 if the root is not visible.

Parameters:: g - a graphics context; clipBounds - a clipped rectangle; insets - insets; bounds - a bounding rectangle; path - a tree path; row - a row; isExpanded - true if the path is expanded; hasBeenExpanded - true if the path has been expanded; isLeaf - true if the path is leaf

paintVerticalPartOfLeg

protected void paintVerticalPartOfLeg(Graphics g, Rectangle clipBounds, Insets insets, TreePath path)

Paints the vertical part of the leg. The receiver should NOT modify clipBounds, insets.

Parameters:: g - a graphics context; clipBounds - a clipped rectangle; insets - insets; path - a tree path

paintExpandControl

protected void paintExpandControl(Graphics g, Rectangle clipBounds, Insets insets, Rectangle bounds, TreePath path, int row, boolean isExpanded, boolean hasBeenExpanded, boolean isLeaf)

Paints the expand (toggle) part of a row. The receiver should NOT modify clipBounds, or insets.

Parameters:: g - a graphics context; clipBounds - a clipped rectangle; insets - insets; bounds - a bounding rectangle; path - a tree path; row - a row; isExpanded - true if the path is expanded; hasBeenExpanded - true if the path has been expanded; isLeaf - true if the row is leaf

paintRow

protected void paintRow(Graphics g, Rectangle clipBounds, Insets insets, Rectangle bounds, TreePath path, int row, boolean isExpanded, boolean hasBeenExpanded, boolean isLeaf)

Paints the renderer part of a row. The receiver should NOT modify clipBounds, or insets.

Parameters:: g - a graphics context; clipBounds - a clipped rectangle; insets - insets; bounds - a bounding rectangle; path - a tree path; row - a row; isExpanded - true if the path is expanded; hasBeenExpanded - true if the path has been expanded; isLeaf - true if the path is leaf

shouldPaintExpandControl

protected boolean shouldPaintExpandControl(TreePath path, int row, boolean isExpanded, boolean hasBeenExpanded, boolean isLeaf)

Returns true if the expand (toggle) control should be drawn for the specified row.

Parameters:: path - a tree path; row - a row; isExpanded - true if the path is expanded; hasBeenExpanded - true if the path has been expanded; isLeaf - true if the row is leaf
Returns:: true if the expand (toggle) control should be drawn for the specified row

paintVerticalLine

protected void paintVerticalLine(Graphics g, JComponent c, int x, int top, int bottom)

Paints a vertical line.

Parameters:: g - a graphics context; c - a component; x - an X coordinate; top - an Y1 coordinate; bottom - an Y2 coordinate

paintHorizontalLine

protected void paintHorizontalLine(Graphics g, JComponent c, int y, int left, int right)

Paints a horizontal line.

Parameters:: g - a graphics context; c - a component; y - an Y coordinate; left - an X1 coordinate; right - an X2 coordinate

getVerticalLegBuffer

protected int getVerticalLegBuffer()

The vertical element of legs between nodes starts at the bottom of the parent node by default. This method makes the leg start below that.

Returns:: the vertical leg buffer

getHorizontalLegBuffer

protected int getHorizontalLegBuffer()

The horizontal element of legs between nodes starts at the right of the left-hand side of the child node by default. This method makes the leg end before that.

Returns:: the horizontal leg buffer

drawCentered

protected void drawCentered(Component c, Graphics graphics, Icon icon, int x, int y)

Draws the icon centered at (x,y).

Parameters:: c - a component; graphics - a graphics context; icon - an icon; x - an X coordinate; y - an Y coordinate

drawDashedHorizontalLine

protected void drawDashedHorizontalLine(Graphics g, int y, int x1, int x2)

Draws a horizontal dashed line. It is assumed x1 <= x2. If x1 is greater than x2, the method draws nothing.

Parameters:: g - an instance of Graphics; y - an Y coordinate; x1 - an X1 coordinate; x2 - an X2 coordinate

drawDashedVerticalLine

protected void drawDashedVerticalLine(Graphics g, int x, int y1, int y2)

Draws a vertical dashed line. It is assumed y1 <= y2. If y1 is greater than y2, the method draws nothing.

Parameters:: g - an instance of Graphics; x - an X coordinate; y1 - an Y1 coordinate; y2 - an Y2 coordinate

getRowX

protected int getRowX(int row, int depth)

Returns the location, along the x-axis, to render a particular row at. The return value does not include any Insets specified on the JTree. This does not check for the validity of the row or depth, it is assumed to be correct and will not throw an Exception if the row or depth doesn't match that of the tree.

Parameters:: row - Row to return x location for; depth - Depth of the row
Returns:: amount to indent the given row.
Since:: 1.5

updateLayoutCacheExpandedNodes

protected void updateLayoutCacheExpandedNodes()

Makes all the nodes that are expanded in JTree expanded in LayoutCache. This invokes updateExpandedDescendants with the root path.

updateExpandedDescendants

protected void updateExpandedDescendants(TreePath path)

Updates the expanded state of all the descendants of path by getting the expanded descendants from the tree and forwarding to the tree state.

Parameters:: path - a tree path

getLastChildPath

protected TreePath getLastChildPath(TreePath parent)

Returns a path to the last child of parent.

Parameters:: parent - a tree path
Returns:: a path to the last child of parent

updateDepthOffset

protected void updateDepthOffset()

Updates how much each depth should be offset by.

updateCellEditor

protected void updateCellEditor()

Updates the cellEditor based on the editability of the JTree that we're contained in. If the tree is editable but doesn't have a cellEditor, a basic one will be used.

updateRenderer

protected void updateRenderer()

Messaged from the tree we're in when the renderer has changed.

configureLayoutCache

protected void configureLayoutCache()

Resets the TreeState instance based on the tree we're providing the look and feel for.

updateSize

protected void updateSize()

Marks the cached size as being invalid, and messages the tree with treeDidChange.

updateCachedPreferredSize

protected void updateCachedPreferredSize()

Updates the preferredSize instance variable, which is returned from getPreferredSize().

For left to right orientations, the size is determined from the current AbstractLayoutCache. For RTL orientations, the preferred size becomes the width minus the minimum x position.

pathWasExpanded

protected void pathWasExpanded(TreePath path)

Messaged from the VisibleTreeNode after it has been expanded.

Parameters:: path - a tree path

pathWasCollapsed

protected void pathWasCollapsed(TreePath path)

Messaged from the VisibleTreeNode after it has collapsed.

Parameters:: path - a tree path

ensureRowsAreVisible

protected void ensureRowsAreVisible(int beginRow, int endRow)

Ensures that the rows identified by beginRow through endRow are visible.

Parameters:: beginRow - the begin row; endRow - the end row

setPreferredMinSize

public void setPreferredMinSize(Dimension newSize)

Sets the preferred minimum size.

Parameters:: newSize - the new preferred size

getPreferredMinSize

public Dimension getPreferredMinSize()

Returns the minimum preferred size.

Returns:: the minimum preferred size

getPreferredSize

public Dimension getPreferredSize(JComponent c)

Returns the preferred size to properly display the tree, this is a cover method for getPreferredSize(c, true).

Overrides:

getPreferredSize in class ComponentUI

Parameters:

c - a component

Returns:

the preferred size to represent the tree in the component

See Also:

getPreferredSize

public Dimension getPreferredSize(JComponent c, boolean checkConsistency)

Returns the preferred size to represent the tree in c. If checkConsistency is true checkConsistency is messaged first.

Parameters:: c - a component; checkConsistency - if true consistency is checked
Returns:: the preferred size to represent the tree in the component

getMinimumSize

public Dimension getMinimumSize(JComponent c)

Returns the minimum size for this component. Which will be the min preferred size or 0, 0.

Overrides:

getMinimumSize in class ComponentUI

Parameters:

c - the component whose minimum size is being queried; this argument is often ignored, but might be used if the UI object is stateless and shared by multiple components

Returns:

a Dimension object or null

See Also:

getMaximumSize

public Dimension getMaximumSize(JComponent c)

Returns the maximum size for this component, which will be the preferred size if the instance is currently in a JTree, or 0, 0.

Overrides:

getMaximumSize in class ComponentUI

Parameters:

c - the component whose maximum size is being queried; this argument is often ignored, but might be used if the UI object is stateless and shared by multiple components

Returns:

a Dimension object or null

See Also:

completeEditing

protected void completeEditing()

Messages to stop the editing session. If the UI the receiver is providing the look and feel for returns true from getInvokesStopCellEditing, stopCellEditing will invoked on the current editor. Then completeEditing will be messaged with false, true, false to cancel any lingering editing.

completeEditing

protected void completeEditing(boolean messageStop, boolean messageCancel, boolean messageTree)

Stops the editing session. If messageStop is true the editor is messaged with stopEditing, if messageCancel is true the editor is messaged with cancelEditing. If messageTree is true the treeModel is messaged with valueForPathChanged.

Parameters:: messageStop - message to stop editing; messageCancel - message to cancel editing; messageTree - message to tree

startEditing

protected boolean startEditing(TreePath path, MouseEvent event)

Will start editing for node if there is a cellEditor and shouldSelectCell returns true.

This assumes that path is valid and visible.

Parameters:: path - a tree path; event - a mouse event
Returns:: true if the editing is successful

checkForClickInExpandControl

protected void checkForClickInExpandControl(TreePath path, int mouseX, int mouseY)

If the mouseX and mouseY are in the expand/collapse region of the row, this will toggle the row.

Parameters:: path - a tree path; mouseX - an X coordinate; mouseY - an Y coordinate

isLocationInExpandControl

protected boolean isLocationInExpandControl(TreePath path, int mouseX, int mouseY)

Returns true if mouseX and mouseY fall in the area of row that is used to expand/collapse the node and the node at row does not represent a leaf.

Parameters:: path - a tree path; mouseX - an X coordinate; mouseY - an Y coordinate
Returns:: true if the mouse cursor fall in the area of row that is used to expand/collapse the node and the node is not a leaf.

handleExpandControlClick

protected void handleExpandControlClick(TreePath path, int mouseX, int mouseY)

Messaged when the user clicks the particular row, this invokes toggleExpandState.

Parameters:: path - a tree path; mouseX - an X coordinate; mouseY - an Y coordinate

toggleExpandState

protected void toggleExpandState(TreePath path)

Expands path if it is not expanded, or collapses row if it is expanded. If expanding a path and JTree scrolls on expand, ensureRowsAreVisible is invoked to scroll as many of the children to visible as possible (tries to scroll to last visible descendant of path).

Parameters:: path - a tree path

isToggleSelectionEvent

protected boolean isToggleSelectionEvent(MouseEvent event)

Returning true signifies a mouse event on the node should toggle the selection of only the row under mouse.

Parameters:: event - a mouse event
Returns:: true if a mouse event on the node should toggle the selection

isMultiSelectEvent

protected boolean isMultiSelectEvent(MouseEvent event)

Returning true signifies a mouse event on the node should select from the anchor point.

Parameters:: event - a mouse event
Returns:: true if a mouse event on the node should select from the anchor point

isToggleEvent

protected boolean isToggleEvent(MouseEvent event)

Returning true indicates the row under the mouse should be toggled based on the event. This is invoked after checkForClickInExpandControl, implying the location is not in the expand (toggle) control.

Parameters:: event - a mouse event
Returns:: true if the row under the mouse should be toggled

selectPathForEvent

protected void selectPathForEvent(TreePath path, MouseEvent event)

Messaged to update the selection based on a MouseEvent over a particular row. If the event is a toggle selection event, the row is either selected, or deselected. If the event identifies a multi selection event, the selection is updated from the anchor point. Otherwise the row is selected, and if the event specified a toggle event the row is expanded/collapsed.

Parameters:: path - the selected path; event - the mouse event

isLeaf

protected boolean isLeaf(int row)

Returns true if the node at row is a leaf.

Parameters:: row - a row
Returns:: true if the node at row is a leaf

updateLeadSelectionRow

protected void updateLeadSelectionRow()

Updates the lead row of the selection.

Since:: 1.7

getLeadSelectionRow

protected int getLeadSelectionRow()

Returns the lead row of the selection.

Returns:: selection lead row
Since:: 1.7

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https://docs.oracle.com/en/java/javase/21/docs/api/java.desktop/javax/swing/plaf/basic/BasicTreeUI.html