HierarchyListener (Java Platform SE 7 )
Keywords: java.awt.event.HierarchyListener interface

java.awt.event

## Interface HierarchyListener

- All Superinterfaces:
    EventListener
  All Known Implementing Classes:
    AWTEventMulticaster

      public interface HierarchyListener
      extends EventListener

  The listener interface for receiving hierarchy changed events. The class that is interested in processing a hierarchy changed event should implement this interface. The listener object created from that class is then registered with a Component using the Component's `addHierarchyListener` method. When the hierarchy to which the Component belongs changes, the `hierarchyChanged` method in the listener object is invoked, and the `HierarchyEvent` is passed to it.

  Hierarchy events are provided for notification purposes ONLY; The AWT will automatically handle changes to the hierarchy internally so that GUI layout, displayability, and visibility work properly regardless of whether a program registers a `HierarchyListener` or not.

  Since:
    1.3
  See Also:
    `HierarchyEvent`

- - ### Method Summary

    Methods
    Modifier and Type | Method and Description
    --- | ---
    `void` | `hierarchyChanged(HierarchyEvent e)` Called when the hierarchy has been changed.

- - ### Method Detail

    - #### hierarchyChanged

          void hierarchyChanged(HierarchyEvent e)

      Called when the hierarchy has been changed. To discern the actual type of change, call `HierarchyEvent.getChangeFlags()`.
      See Also:
        `HierarchyEvent.getChangeFlags()`

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