Java Swing Focus hasFocus(Component component)

Description

has Focus

License

Apache License

Return

true if javax.swing.SwingUtilities.findFocusOwner(component) != null

Declaration

public static boolean hasFocus(Component component) 

Method Source Code

//package com.java2s;
/*//from  w ww .  j a v  a 2 s . c  o  m
 * Copyright 2000-2009 JetBrains s.r.o.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import java.awt.*;

public class Main {
    /**
     * @return true if javax.swing.SwingUtilities.findFocusOwner(component) != null
     */
    public static boolean hasFocus(Component component) {
        Component focusOwner = findFocusOwner(component);
        return focusOwner != null;
    }

    private static Component findFocusOwner(Component c) {
        Component focusOwner = KeyboardFocusManager
                .getCurrentKeyboardFocusManager().getFocusOwner();

        // verify focusOwner is a descendant of c
        for (Component temp = focusOwner; temp != null; temp = (temp instanceof Window) ? null
                : temp.getParent()) {
            if (temp == c) {
                return focusOwner;
            }
        }

        return null;
    }
}

Related

1. focusLater(final Component component)
2. focusOnOpen(final JComponent component)
3. getFocusableComponentOrChild(Component c, boolean deepest)
4. getFocusableComponentOrChild(Component c, boolean deepest)
5. getPermanentFocusOwner()
6. hasFocusOwner(final Component component)
7. installDefaultFocusHandling(Container c)
8. installFocusCycleRoot(Container c, FocusTraversalPolicy cyclePolicy)
9. installJComponentRepainterOnWindowFocusChanged( JComponent component)