Interface TreeSelectionModel

All Known Implementing Classes:: DefaultTreeSelectionModel, JTree.EmptySelectionModel

public interface TreeSelectionModel

This interface represents the current state of the selection for the tree component. For information and examples of using tree selection models, see How to Use Trees in The Java Tutorial.

The state of the tree selection is characterized by a set of TreePaths, and optionally a set of integers. The mapping from TreePath to integer is done by way of an instance of RowMapper. It is not necessary for a TreeSelectionModel to have a RowMapper to correctly operate, but without a RowMapper getSelectionRows will return null.

A TreeSelectionModel can be configured to allow only one path (SINGLE_TREE_SELECTION) a number of contiguous paths (CONTIGUOUS_TREE_SELECTION) or a number of discontiguous paths (DISCONTIGUOUS_TREE_SELECTION). A RowMapper is used to determine if TreePaths are contiguous. In the absence of a RowMapper CONTIGUOUS_TREE_SELECTION and DISCONTIGUOUS_TREE_SELECTION behave the same, that is they allow any number of paths to be contained in the TreeSelectionModel.

For a selection model of CONTIGUOUS_TREE_SELECTION any time the paths are changed (setSelectionPath, addSelectionPath ...) the TreePaths are again checked to make they are contiguous. A check of the TreePaths can also be forced by invoking resetRowSelection. How a set of discontiguous TreePaths is mapped to a contiguous set is left to implementors of this interface to enforce a particular policy.

Implementations should combine duplicate TreePaths that are added to the selection. For example, the following code

TreePath[] paths = new TreePath[] { treePath, treePath };
   treeSelectionModel.setSelectionPaths(paths);

should result in only one path being selected: treePath, and not two copies of treePath.

The lead TreePath is the last path that was added (or set). The lead row is then the row that corresponds to the TreePath as determined from the RowMapper.

Field Summary

Fields
Modifier and Type	Field	Description
`static int`	`CONTIGUOUS_TREE_SELECTION`	Selection can only be contiguous.
`static int`	`DISCONTIGUOUS_TREE_SELECTION`	Selection can contain any number of items that are not necessarily contiguous.
`static int`	`SINGLE_TREE_SELECTION`	Selection can only contain one path at a time.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`void`	`addPropertyChangeListener(PropertyChangeListener listener)`	Adds a PropertyChangeListener to the listener list.
`void`	`addSelectionPath(TreePath path)`	Adds path to the current selection.
`void`	`addSelectionPaths(TreePath[] paths)`	Adds paths to the current selection.
`void`	`addTreeSelectionListener(TreeSelectionListener x)`	Adds x to the list of listeners that are notified each time the set of selected TreePaths changes.
`void`	`clearSelection()`	Empties the current selection.
`TreePath`	`getLeadSelectionPath()`	Returns the last path that was added.
`int`	`getLeadSelectionRow()`	Returns the lead selection index.
`int`	`getMaxSelectionRow()`	Returns the largest value obtained from the RowMapper for the current set of selected TreePaths.
`int`	`getMinSelectionRow()`	Returns the smallest value obtained from the RowMapper for the current set of selected TreePaths.
`RowMapper`	`getRowMapper()`	Returns the RowMapper instance that is able to map a TreePath to a row.
`int`	`getSelectionCount()`	Returns the number of paths that are selected.
`int`	`getSelectionMode()`	Returns the current selection mode, one of `SINGLE_TREE_SELECTION`, `CONTIGUOUS_TREE_SELECTION` or `DISCONTIGUOUS_TREE_SELECTION`.
`TreePath`	`getSelectionPath()`	Returns the first path in the selection.
`TreePath[]`	`getSelectionPaths()`	Returns the paths in the selection.
`int[]`	`getSelectionRows()`	Returns all of the currently selected rows.
`boolean`	`isPathSelected(TreePath path)`	Returns true if the path, `path`, is in the current selection.
`boolean`	`isRowSelected(int row)`	Returns true if the row identified by `row` is selected.
`boolean`	`isSelectionEmpty()`	Returns true if the selection is currently empty.
`void`	`removePropertyChangeListener(PropertyChangeListener listener)`	Removes a PropertyChangeListener from the listener list.
`void`	`removeSelectionPath(TreePath path)`	Removes path from the selection.
`void`	`removeSelectionPaths(TreePath[] paths)`	Removes paths from the selection.
`void`	`removeTreeSelectionListener(TreeSelectionListener x)`	Removes x from the list of listeners that are notified each time the set of selected TreePaths changes.
`void`	`resetRowSelection()`	Updates this object's mapping from TreePaths to rows.
`void`	`setRowMapper(RowMapper newMapper)`	Sets the RowMapper instance.
`void`	`setSelectionMode(int mode)`	Sets the selection model, which must be one of SINGLE_TREE_SELECTION, CONTIGUOUS_TREE_SELECTION or DISCONTIGUOUS_TREE_SELECTION.
`void`	`setSelectionPath(TreePath path)`	Sets the selection to path.
`void`	`setSelectionPaths(TreePath[] paths)`	Sets the selection to path.

Field Detail

SINGLE_TREE_SELECTION

static final int SINGLE_TREE_SELECTION

Selection can only contain one path at a time.

See Also:: Constant Field Values

CONTIGUOUS_TREE_SELECTION

static final int CONTIGUOUS_TREE_SELECTION

Selection can only be contiguous. This will only be enforced if a RowMapper instance is provided. That is, if no RowMapper is set this behaves the same as DISCONTIGUOUS_TREE_SELECTION.

See Also:: Constant Field Values

DISCONTIGUOUS_TREE_SELECTION

static final int DISCONTIGUOUS_TREE_SELECTION

Selection can contain any number of items that are not necessarily contiguous.

See Also:: Constant Field Values

Method Detail

setSelectionMode

void setSelectionMode(int mode)

Sets the selection model, which must be one of SINGLE_TREE_SELECTION, CONTIGUOUS_TREE_SELECTION or DISCONTIGUOUS_TREE_SELECTION.

This may change the selection if the current selection is not valid for the new mode. For example, if three TreePaths are selected when the mode is changed to SINGLE_TREE_SELECTION, only one TreePath will remain selected. It is up to the particular implementation to decide what TreePath remains selected.

Parameters:: mode - selection mode to be set

getSelectionMode

int getSelectionMode()

Returns the current selection mode, one of SINGLE_TREE_SELECTION, CONTIGUOUS_TREE_SELECTION or DISCONTIGUOUS_TREE_SELECTION.

Returns:: the current selection mode

setSelectionPath

void setSelectionPath(TreePath path)

Sets the selection to path. If this represents a change, then the TreeSelectionListeners are notified. If path is null, this has the same effect as invoking clearSelection.

Parameters:: path - new path to select

setSelectionPaths

void setSelectionPaths(TreePath[] paths)

Sets the selection to path. If this represents a change, then the TreeSelectionListeners are notified. If paths is null, this has the same effect as invoking clearSelection.

Parameters:: paths - new selection

addSelectionPath

void addSelectionPath(TreePath path)

Adds path to the current selection. If path is not currently in the selection the TreeSelectionListeners are notified. This has no effect if path is null.

Parameters:: path - the new path to add to the current selection

addSelectionPaths

void addSelectionPaths(TreePath[] paths)

Adds paths to the current selection. If any of the paths in paths are not currently in the selection the TreeSelectionListeners are notified. This has no effect if paths is null.

Parameters:: paths - the new paths to add to the current selection

removeSelectionPath

void removeSelectionPath(TreePath path)

Removes path from the selection. If path is in the selection The TreeSelectionListeners are notified. This has no effect if path is null.

Parameters:: path - the path to remove from the selection

removeSelectionPaths

void removeSelectionPaths(TreePath[] paths)

Removes paths from the selection. If any of the paths in paths are in the selection, the TreeSelectionListeners are notified. This method has no effect if paths is null.

Parameters:: paths - the path to remove from the selection

getSelectionPath

TreePath getSelectionPath()

Returns the first path in the selection. How first is defined is up to implementors, and may not necessarily be the TreePath with the smallest integer value as determined from the RowMapper.

Returns:: the first path in the selection

getSelectionPaths

TreePath[] getSelectionPaths()

Returns the paths in the selection. This will return null (or an empty array) if nothing is currently selected.

Returns:: the paths in the selection

getSelectionCount

int getSelectionCount()

Returns the number of paths that are selected.

Returns:: the number of paths that are selected

isPathSelected

boolean isPathSelected(TreePath path)

Returns true if the path, path, is in the current selection.

Parameters:: path - the path to be loked for
Returns:: whether the path is in the current selection

isSelectionEmpty

boolean isSelectionEmpty()

Returns true if the selection is currently empty.

Returns:: whether the selection is currently empty

clearSelection

void clearSelection()

Empties the current selection. If this represents a change in the current selection, the selection listeners are notified.

setRowMapper

void setRowMapper(RowMapper newMapper)

Sets the RowMapper instance. This instance is used to determine the row for a particular TreePath.

Parameters:: newMapper - RowMapper to be set

getRowMapper

RowMapper getRowMapper()

Returns the RowMapper instance that is able to map a TreePath to a row.

Returns:: the RowMapper instance that is able to map a TreePath to a row

getSelectionRows

int[] getSelectionRows()

Returns all of the currently selected rows. This will return null (or an empty array) if there are no selected TreePaths or a RowMapper has not been set.

Returns:: all of the currently selected rows

getMinSelectionRow

int getMinSelectionRow()

Returns the smallest value obtained from the RowMapper for the current set of selected TreePaths. If nothing is selected, or there is no RowMapper, this will return -1.

Returns:: the smallest value obtained from the RowMapper for the current set of selected TreePaths

getMaxSelectionRow

int getMaxSelectionRow()

Returns the largest value obtained from the RowMapper for the current set of selected TreePaths. If nothing is selected, or there is no RowMapper, this will return -1.

Returns:: the largest value obtained from the RowMapper for the current set of selected TreePaths

isRowSelected

boolean isRowSelected(int row)

Returns true if the row identified by row is selected.

Parameters:: row - row to check
Returns:: whether the row is selected

resetRowSelection

void resetRowSelection()

Updates this object's mapping from TreePaths to rows. This should be invoked when the mapping from TreePaths to integers has changed (for example, a node has been expanded).

You do not normally have to call this; JTree and its associated listeners will invoke this for you. If you are implementing your own view class, then you will have to invoke this.

getLeadSelectionRow

int getLeadSelectionRow()

Returns the lead selection index. That is the last index that was added.

Returns:: the lead selection index

getLeadSelectionPath

TreePath getLeadSelectionPath()

Returns the last path that was added. This may differ from the leadSelectionPath property maintained by the JTree.

Returns:: the last path that was added

addPropertyChangeListener

void addPropertyChangeListener(PropertyChangeListener listener)

Adds a PropertyChangeListener to the listener list. The listener is registered for all properties.

A PropertyChangeEvent will get fired when the selection mode changes.

Parameters:: listener - the PropertyChangeListener to be added

removePropertyChangeListener

void removePropertyChangeListener(PropertyChangeListener listener)

Removes a PropertyChangeListener from the listener list. This removes a PropertyChangeListener that was registered for all properties.

Parameters:: listener - the PropertyChangeListener to be removed

addTreeSelectionListener

void addTreeSelectionListener(TreeSelectionListener x)

Adds x to the list of listeners that are notified each time the set of selected TreePaths changes.

Parameters:: x - the new listener to be added

removeTreeSelectionListener

void removeTreeSelectionListener(TreeSelectionListener x)

Removes x from the list of listeners that are notified each time the set of selected TreePaths changes.

Parameters:: x - the listener to remove