focus_childfocus.html
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<TITLE>Activating a Keystroke When Any Child Component Has Focus
(Java Developers Almanac Example)
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<h3>
e625.
Activating a Keystroke When Any Child Component Has Focus</h3>
Normally, a keystroke registered on a component is activated when the
component has the focus. This type of activation condition is called
<code>WHEN_FOCUSED</code>. It is possible to specify that a keystroke be
activated if it or any child or descendant component has the focus.
This type of keystroke activation condition is called
<code>WHEN_ANCESTOR_OF_FOCUSED_COMPONENT</code>.
<P> An example where this type of keystroke activation condition is
useful is in the case of a scrollpane that handles scrolling
navigation keystrokes even when the child component has the focus.
<P> There are three types of activation conditions available:
<code>WHEN_FOCUSED</code>, <code>WHEN_ANCESTOR_OF_FOCUSED_COMPONENT</code>, and
<code>WHEN_IN_FOCUSED_WINDOW</code>. See
<a href="../java.awt/focus_WindowFocus.html" class="eglink"><font size="-1"><b>e624</b> Activating a Keystroke When Any Component in the Window Has Focus</font></a> for more details about these
activation conditions.
<pre>
// To create an action, see <a href="../javax.swing/CreateAction.html" class="eglink"><font size="-1"><b>e854</b> Creating an Action</font></a>
// Register keystroke
<font color="#0066ff"><i>component</i></font>.getInputMap(JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT).put(
KeyStroke.getKeyStroke(<font color="#0066ff"><i>"F2"</i></font>), <font color="#0066ff"><i>action</i></font>.getValue(Action.NAME));
// Register action
<font color="#0066ff"><i>component</i></font>.getActionMap().put(<font color="#0066ff"><i>action</i></font>.getValue(Action.NAME), action);
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Related Examples
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e610. <a class="eglink" href="focus_FindFocus.html?l=rel">
Determining Which Component or Window Has the Focus
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e611. <a class="eglink" href="focus_NoFocus.html?l=rel">
Preventing a Component from Gaining the Focus
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e612. <a class="eglink" href="focus_NoFocusWindow.html?l=rel">
Preventing a Window from Gaining the Focus
</a>
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e613. <a class="eglink" href="focus_FocusEvents.html?l=rel">
Listening to All Focus Changes Between Components in an Application
</a>
<br>
e614. <a class="eglink" href="focus_FocusTravKeyComp.html?l=rel">
Setting Focus Traversal Keys in a Component
</a>
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e615. <a class="eglink" href="focus_FocusTravKey.html?l=rel">
Setting Focus Traversal Keys for the Entire Application
</a>
<br>
e616. <a class="eglink" href="focus_FocusTrans.html?l=rel">
Moving the Focus to the Next or Previous Focusable Component
</a>
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e617. <a class="eglink" href="focus_NextFocus.html?l=rel">
Modifying the Focus Traversal Order
</a>
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e618. <a class="eglink" href="focus_InitialFocus.html?l=rel">
Setting the Initial Focused Component in a Window
</a>
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e619. <a class="eglink" href="focus_FindNextFocus.html?l=rel">
Finding the Next Focusable Component
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e620. <a class="eglink" href="focus_TempFocus.html?l=rel">
Determining If a Focus Lost Is Temporary or Permanent
</a>
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e621. <a class="eglink" href="focus_OppositeFocus.html?l=rel">
Determining the Opposite Component of a Focus Event
</a>
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e622. <a class="eglink" href="focus_ValidateFocus.html?l=rel">
Validating a JTextField When Permanently Losing the Focus
</a>
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e623. <a class="eglink" href="focus_RemoveFocus.html?l=rel">
Removing the Focus from the Application
</a>
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e624. <a class="eglink" href="focus_WindowFocus.html?l=rel">
Activating a Keystroke When Any Component in the Window Has Focus
</a>
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See also:
<a class="eglink" href="/egs/java.awt/pkg.html?l=rel#Colors">
Colors
</a>
<a class="eglink" href="/egs/java.awt/pkg.html?l=rel#Components">
Components
</a>
<a class="eglink" href="/egs/java.awt/pkg.html?l=rel#Containers">
Containers
</a>
<a class="eglink" href="/egs/java.awt/pkg.html?l=rel#Cursors">
Cursors
</a>
<a class="eglink" href="/egs/java.awt/pkg.html?l=rel#Drawing">
Drawing
</a>
<a class="eglink" href="/egs/java.awt/pkg.html?l=rel#Events">
Events
</a>
<a class="eglink" href="/egs/java.awt/pkg.html?l=rel#Frames">
Frames
</a>
<a class="eglink" href="/egs/java.awt/pkg.html?l=rel#GridBagLayout">
GridBagLayout
</a>
<a class="eglink" href="/egs/java.awt/pkg.html?l=rel#Images">
Images
</a>
<a class="eglink" href="/egs/java.awt/pkg.html?l=rel#Shapes">
Shapes
</a>
<a class="eglink" href="/egs/java.awt/pkg.html?l=rel#Simulating%20Events">
Simulating Events
</a>
<a class="eglink" href="/egs/java.awt/pkg.html?l=rel#Text">
Text
</a>
<a class="eglink" href="/egs/java.awt/pkg.html?l=rel#The%20Screen">
The Screen
</a>
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