Class FixedHeightLayoutCache

java.lang.Object

javax.swing.tree.AbstractLayoutCache

javax.swing.tree.FixedHeightLayoutCache

All Implemented Interfaces:: RowMapper

public class FixedHeightLayoutCache extends AbstractLayoutCache

NOTE: This will become more open in a future release.

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.

Nested Class Summary

Nested classes/interfaces declared in class AbstractLayoutCache

AbstractLayoutCache.NodeDimensions

Modifier and Type	Class	Description
`static class`	`AbstractLayoutCache.NodeDimensions`	Used by `AbstractLayoutCache` to determine the size and x origin of a particular node.

Field Summary

Fields declared in class AbstractLayoutCache

nodeDimensions, rootVisible, rowHeight, treeModel, treeSelectionModel

Modifier and Type	Field	Description
`protected AbstractLayoutCache.NodeDimensions`	`nodeDimensions`	Object responsible for getting the size of a node.
`protected boolean`	`rootVisible`	True if the root node is displayed, false if its children are the highest visible nodes.
`protected int`	`rowHeight`	Height to use for each row.
`protected TreeModel`	`treeModel`	Model providing information.
`protected TreeSelectionModel`	`treeSelectionModel`	Selection model.

Constructor Summary

Constructor	Description
`FixedHeightLayoutCache()`	Constructs a `FixedHeightLayoutCache`.

Method Summary

Modifier and Type	Method	Description
`Rectangle`	`getBounds(TreePath path, Rectangle placeIn)`	Returns a rectangle giving the bounds needed to draw path.
`boolean`	`getExpandedState(TreePath path)`	Returns true if the path is expanded, and visible.
`TreePath`	`getPathClosestTo(int x, int y)`	Returns the path to the node that is closest to x,y.
`TreePath`	`getPathForRow(int row)`	Returns the path for passed in row.
`int`	`getRowCount()`	Returns the number of visible rows.
`int`	`getRowForPath(TreePath path)`	Returns the row that the last item identified in path is visible at.
`int`	`getVisibleChildCount(TreePath path)`	Returns the number of visible children for row.
`Enumeration<TreePath>`	`getVisiblePathsFrom(TreePath path)`	Returns an Enumerator that increments over the visible paths starting at the passed in location.
`void`	`invalidatePathBounds(TreePath path)`	Does nothing, FixedHeightLayoutCache doesn't cache width, and that is all that could change.
`void`	`invalidateSizes()`	Informs the TreeState that it needs to recalculate all the sizes it is referencing.
`boolean`	`isExpanded(TreePath path)`	Returns true if the value identified by row is currently expanded.
`void`	`setExpandedState(TreePath path, boolean isExpanded)`	Marks the path `path` expanded state to `isExpanded`.
`void`	`setModel(TreeModel newModel)`	Sets the TreeModel that will provide the data.
`void`	`setRootVisible(boolean rootVisible)`	Determines whether or not the root node from the TreeModel is visible.
`void`	`setRowHeight(int rowHeight)`	Sets the height of each cell.
`void`	`treeNodesChanged(TreeModelEvent e)`	Invoked after a node (or a set of siblings) has changed in some way.
`void`	`treeNodesInserted(TreeModelEvent e)`	Invoked after nodes have been inserted into the tree.
`void`	`treeNodesRemoved(TreeModelEvent e)`	Invoked after nodes have been removed from the tree.
`void`	`treeStructureChanged(TreeModelEvent e)`	Invoked after the tree has drastically changed structure from a given node down.

Methods declared in class AbstractLayoutCache

getModel, getNodeDimensions, getNodeDimensions, getPreferredHeight, getPreferredWidth, getRowHeight, getRowsForPaths, getSelectionModel, isFixedRowHeight, isRootVisible, setNodeDimensions, setSelectionModel

Modifier and Type	Method	Description
`TreeModel`	`getModel()`	Returns the `TreeModel` that is providing the data.
`AbstractLayoutCache.NodeDimensions`	`getNodeDimensions()`	Returns the object that renders nodes in the tree, and which is responsible for calculating the dimensions of individual nodes.
`protected Rectangle`	`getNodeDimensions(Object value, int row, int depth, boolean expanded, Rectangle placeIn)`	Returns, by reference in `placeIn`, the size needed to represent `value`.
`int`	`getPreferredHeight()`	Returns the preferred height.
`int`	`getPreferredWidth(Rectangle bounds)`	Returns the preferred width for the passed in region.
`int`	`getRowHeight()`	Returns the height of each row.
`int[]`	`getRowsForPaths(TreePath[] paths)`	Returns the rows that the `TreePath` instances in `path` are being displayed at.
`TreeSelectionModel`	`getSelectionModel()`	Returns the model used to maintain the selection.
`protected boolean`	`isFixedRowHeight()`	Returns true if the height of each row is a fixed size.
`boolean`	`isRootVisible()`	Returns true if the root node of the tree is displayed.
`void`	`setNodeDimensions(AbstractLayoutCache.NodeDimensions nd)`	Sets the renderer that is responsible for drawing nodes in the tree and which is therefore responsible for calculating the dimensions of individual nodes.
`void`	`setSelectionModel(TreeSelectionModel newLSM)`	Sets the `TreeSelectionModel` used to manage the selection to new LSM.

Methods declared in class Object

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

Modifier and Type	Method	Description
`protected Object`	`clone()`	Creates and returns a copy of this object.
`boolean`	`equals(Object obj)`	Indicates whether some other object is "equal to" this one.
`protected void`	`finalize()`	Deprecated, for removal: This API element is subject to removal in a future version. Finalization is deprecated and subject to removal in a future release.
`final Class<?>`	`getClass()`	Returns the runtime class of this `Object`.
`int`	`hashCode()`	Returns a hash code value for this object.
`final void`	`notify()`	Wakes up a single thread that is waiting on this object's monitor.
`final void`	`notifyAll()`	Wakes up all threads that are waiting on this object's monitor.
`String`	`toString()`	Returns a string representation of the object.
`final void`	`wait()`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted.
`final void`	`wait(long timeoutMillis)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
`final void`	`wait(long timeoutMillis, int nanos)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

Constructor Details

FixedHeightLayoutCache

public FixedHeightLayoutCache()

Constructs a FixedHeightLayoutCache.

Method Details

setModel

public void setModel(TreeModel newModel)

Sets the TreeModel that will provide the data.

Overrides:: setModel in class AbstractLayoutCache
Parameters:: newModel - the TreeModel that is to provide the data

setRootVisible

public void setRootVisible(boolean rootVisible)

Determines whether or not the root node from the TreeModel is visible.

Overrides:

setRootVisible in class AbstractLayoutCache

Parameters:

rootVisible - true if the root node of the tree is to be displayed

See Also:

setRowHeight

public void setRowHeight(int rowHeight)

Sets the height of each cell. If rowHeight is less than or equal to 0 this will throw an IllegalArgumentException.

Overrides:: setRowHeight in class AbstractLayoutCache
Parameters:: rowHeight - the height of each cell, in pixels

getRowCount

public int getRowCount()

Returns the number of visible rows.

Specified by:: getRowCount in class AbstractLayoutCache
Returns:: the number of rows being displayed

invalidatePathBounds

public void invalidatePathBounds(TreePath path)

Does nothing, FixedHeightLayoutCache doesn't cache width, and that is all that could change.

Specified by:: invalidatePathBounds in class AbstractLayoutCache
Parameters:: path - the path being updated

invalidateSizes

public void invalidateSizes()

Informs the TreeState that it needs to recalculate all the sizes it is referencing.

Specified by:: invalidateSizes in class AbstractLayoutCache

isExpanded

public boolean isExpanded(TreePath path)

Returns true if the value identified by row is currently expanded.

Specified by:: isExpanded in class AbstractLayoutCache
Parameters:: path - TreePath to check
Returns:: whether TreePath is expanded

getBounds

public Rectangle getBounds(TreePath path, Rectangle placeIn)

Returns a rectangle giving the bounds needed to draw path.

Specified by:: getBounds in class AbstractLayoutCache
Parameters:: path - a TreePath specifying a node; placeIn - a Rectangle object giving the available space
Returns:: a Rectangle object specifying the space to be used

getPathForRow

public TreePath getPathForRow(int row)

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

Specified by:: getPathForRow in class AbstractLayoutCache
Parameters:: row - the row being queried
Returns:: the TreePath for the given row

getRowForPath

public int getRowForPath(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 AbstractLayoutCache
Parameters:: path - the TreePath being queried
Returns:: the row where the last item in path is visible or -1 if any elements in path aren't currently visible

getPathClosestTo

public TreePath getPathClosestTo(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:: getPathClosestTo in class AbstractLayoutCache
Parameters:: x - the horizontal component of the desired location; y - the vertical component of the desired location
Returns:: the TreePath closest to the specified point

getVisibleChildCount

public int getVisibleChildCount(TreePath path)

Returns the number of visible children for row.

Specified by:: getVisibleChildCount in class AbstractLayoutCache
Parameters:: path - the path being queried
Returns:: the number of visible children for the specified path

getVisiblePathsFrom

public Enumeration<TreePath> getVisiblePathsFrom(TreePath path)

Returns an Enumerator that increments over the visible paths starting at the passed in location. The ordering of the enumeration is based on how the paths are displayed.

Specified by:: getVisiblePathsFrom in class AbstractLayoutCache
Parameters:: path - the starting location for the enumeration
Returns:: the Enumerator starting at the desired location

setExpandedState

public void setExpandedState(TreePath path, boolean isExpanded)

Marks the path path expanded state to isExpanded.

Specified by:: setExpandedState in class AbstractLayoutCache
Parameters:: path - the path being expanded or collapsed; isExpanded - true if the path should be expanded, false otherwise

getExpandedState

public boolean getExpandedState(TreePath path)

Returns true if the path is expanded, and visible.

Specified by:: getExpandedState in class AbstractLayoutCache
Parameters:: path - the path being queried
Returns:: true if the path is expanded and visible, false otherwise

treeNodesChanged

public void treeNodesChanged(TreeModelEvent e)

Invoked after a node (or a set of siblings) has changed in some way. The node(s) have not changed locations in the tree or altered their children arrays, but other attributes have changed and may affect presentation. Example: the name of a file has changed, but it is in the same location in the file system.

e.path() returns the path the parent of the changed node(s).

e.childIndices() returns the index(es) of the changed node(s).

Specified by:: treeNodesChanged in class AbstractLayoutCache
Parameters:: e - the TreeModelEvent

treeNodesInserted

public void treeNodesInserted(TreeModelEvent e)

Invoked after nodes have been inserted into the tree.

e.path() returns the parent of the new nodes

e.childIndices() returns the indices of the new nodes in ascending order.

Specified by:: treeNodesInserted in class AbstractLayoutCache
Parameters:: e - the TreeModelEvent

treeNodesRemoved

public void treeNodesRemoved(TreeModelEvent e)

Invoked after nodes have been removed from the tree. Note that if a subtree is removed from the tree, this method may only be invoked once for the root of the removed subtree, not once for each individual set of siblings removed.

e.path() returns the former parent of the deleted nodes.

e.childIndices() returns the indices the nodes had before they were deleted in ascending order.

Specified by:: treeNodesRemoved in class AbstractLayoutCache
Parameters:: e - the TreeModelEvent

treeStructureChanged

public void treeStructureChanged(TreeModelEvent e)

Invoked after the tree has drastically changed structure from a given node down. If the path returned by e.getPath() is of length one and the first element does not identify the current root node the first element should become the new root of the tree.

e.path() holds the path to the node.

e.childIndices() returns null.

Specified by:: treeStructureChanged in class AbstractLayoutCache
Parameters:: e - the TreeModelEvent

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