bibliothek.gui.dock.util
Class NullWindowProvider

java.lang.Object
  extended by bibliothek.gui.dock.util.NullWindowProvider
All Implemented Interfaces:
WindowProvider

public class NullWindowProvider
extends Object
implements WindowProvider

A window provider that never returns a window.

Author:
Benjamin Sigg

Constructor Summary
NullWindowProvider()
           
 
Method Summary
 void addWindowProviderListener(WindowProviderListener listener)
          Adds a new listener to this provider.
 boolean isShowing()
          Tells whether this window represents a window that is visible.
 void removeWindowProviderListener(WindowProviderListener listener)
          Removes a listener from this provider
 Window searchWindow()
          Tries to find a window.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

NullWindowProvider

public NullWindowProvider()
Method Detail

addWindowProviderListener

public void addWindowProviderListener(WindowProviderListener listener)
Description copied from interface: WindowProvider
Adds a new listener to this provider. The listener should be called when the window provided by this object changes.

Specified by:
addWindowProviderListener in interface WindowProvider
Parameters:
listener - the new listener

removeWindowProviderListener

public void removeWindowProviderListener(WindowProviderListener listener)
Description copied from interface: WindowProvider
Removes a listener from this provider

Specified by:
removeWindowProviderListener in interface WindowProvider
Parameters:
listener - the listener to remove

searchWindow

public Window searchWindow()
Description copied from interface: WindowProvider
Tries to find a window. The result should either be a Frame or a Dialog, and a plain Window only as last resort. If possible the main-frame or another important window that will not be closed soon should be returned. Visible windows are preferred over non visible ones. This method is not guaranteed to have success, null is a valid result. This method is not required to return always the same window, however the WindowProviderListeners should be informed when the result changes.

Specified by:
searchWindow in interface WindowProvider
Returns:
if possible a visible Frame which won't be closed in the near future, any window which does not fulfill the requirements or null if no window is available at all.

isShowing

public boolean isShowing()
Description copied from interface: WindowProvider
Tells whether this window represents a window that is visible. Under normal circumstances this method would return:
Window window = sarchWindow();
return window == null ? false : window.isShowing();

This method is explicitly allowed to return any value it likes. The result of this method does not have to correspond with reality.

Specified by:
isShowing in interface WindowProvider
Returns:
whether this providers window is visible or not