Uses of Class javax.swing.event.TreeExpansionEvent (Java Platform SE 8 )
Date: 2026-01-21

## Uses of Class
javax.swing.event.TreeExpansionEvent

- Packages that use TreeExpansionEvent
  Package | Description
  --- | ---
  javax.swing | Provides a set of "lightweight" (all-Java language) components that, to the maximum degree possible, work the same on all platforms.
  javax.swing.event | Provides for events fired by Swing components.
  javax.swing.plaf.basic | Provides user interface objects built according to the Basic look and feel.
  javax.swing.tree | Provides classes and interfaces for dealing with `javax.swing.JTree`.

- - ### Uses of TreeExpansionEvent in javax.swing

    Methods in javax.swing with parameters of type TreeExpansionEvent
    Modifier and Type | Method and Description
    --- | ---
    `void` | JTree.AccessibleJTree.`treeCollapsed(TreeExpansionEvent e)` Tree Collapsed notification.
    `void` | JTree.AccessibleJTree.`treeExpanded(TreeExpansionEvent e)` Tree Model Expansion notification.

  - ### Uses of TreeExpansionEvent in javax.swing.event

    Methods in javax.swing.event with parameters of type TreeExpansionEvent
    Modifier and Type | Method and Description
    --- | ---
    `void` | TreeExpansionListener.`treeCollapsed(TreeExpansionEvent event)` Called whenever an item in the tree has been collapsed.
    `void` | TreeExpansionListener.`treeExpanded(TreeExpansionEvent event)` Called whenever an item in the tree has been expanded.
    `void` | TreeWillExpandListener.`treeWillCollapse(TreeExpansionEvent event)` Invoked whenever a node in the tree is about to be collapsed.
    `void` | TreeWillExpandListener.`treeWillExpand(TreeExpansionEvent event)` Invoked whenever a node in the tree is about to be expanded.

  - ### Uses of TreeExpansionEvent in javax.swing.plaf.basic

    Methods in javax.swing.plaf.basic with parameters of type TreeExpansionEvent
    Modifier and Type | Method and Description
    --- | ---
    `void` | BasicTreeUI.TreeExpansionHandler.`treeCollapsed(TreeExpansionEvent event)` Called whenever an item in the tree has been collapsed.
    `void` | BasicTreeUI.TreeExpansionHandler.`treeExpanded(TreeExpansionEvent event)` Called whenever an item in the tree has been expanded.

  - ### Uses of TreeExpansionEvent in javax.swing.tree

    Fields in javax.swing.tree declared as TreeExpansionEvent
    Modifier and Type | Field and Description
    --- | ---
    `protected TreeExpansionEvent` | ExpandVetoException.`event` The event that the exception was created for.

    Constructors in javax.swing.tree with parameters of type TreeExpansionEvent
    Constructor and Description
    `ExpandVetoException(TreeExpansionEvent event)` Constructs an ExpandVetoException object with no message.
    `ExpandVetoException(TreeExpansionEvent event, String message)` Constructs an ExpandVetoException object with the specified message.

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