TreeWillExpandListener (Java Platform SE 8 )

All Superinterfaces:

EventListener
```
public interface TreeWillExpandListener
extends EventListener
```
当树展开或折叠节点时通知的侦听器。有关更多信息和示例，请参阅How to Write a Tree-Will-Expand Listener “Java教程 ”中的一节。

方法摘要

所有方法接口方法抽象方法
Modifier and Type	Method and Description
`void`	`treeWillCollapse(TreeExpansionEvent event)` 每当树中的节点即将被折叠时调用。
`void`	`treeWillExpand(TreeExpansionEvent event)` 每当树中的节点即将被扩展时调用。

- 方法详细信息
  - treeWillExpand
```
void treeWillExpand(TreeExpansionEvent event)
             throws ExpandVetoException
```
    每当树中的节点即将被扩展时调用。
    
    异常
    
    ExpandVetoException
  - treeWillCollapse
```
void treeWillCollapse(TreeExpansionEvent event)
               throws ExpandVetoException
```
    每当树中的节点即将被折叠时调用。
    
    异常
    
    ExpandVetoException

Submit a bug or feature
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
Copyright © 1993, 2014, Oracle and/or its affiliates. All rights reserved.

Interface TreeWillExpandListener

方法摘要

方法详细信息

treeWillExpand

treeWillCollapse