src/java/org/apache/log4j/chainsaw/helper/SwingHelper.java

/*
 * Copyright 1999,2004 The Apache Software Foundation.
 * 
 * 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.
 */

package org.apache.log4j.chainsaw.helper;

import java.awt.Component;
import java.awt.Dimension;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;

import javax.swing.AbstractAction;
import javax.swing.Action;
import javax.swing.InputMap;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JDialog;
import javax.swing.KeyStroke;

/**
 * A collection of standard utility methods for use within Swing.
 * 
 * @author Paul Smith <psmith@apache.org>
 *
 */
public final class SwingHelper {
  /**
   * Centers the Component on screen.
   *
   * @param component
   */
  public static void centerOnScreen(Component component) {
    Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
    component.setLocation(
      (screenSize.width / 2) - (component.getWidth() / 2),
      (screenSize.height / 2) - (component.getHeight() / 2));
  }
  
  /**
   * This method configures a standard Cancel action, bound to the ESC key, to dispose of the dialog,
   * and sets the buttons action to be this action, and adds the action to the dialog's rootPane 
   * action map
   * @param dialog
   * @param cancelButton
   */
  public static void configureCancelForDialog(final JDialog dialog, JButton cancelButton) {
    String CANCEL_ACTION_KEY = "CANCEL_ACTION_KEY";
    int noModifiers = 0;
    KeyStroke escapeKey = KeyStroke.getKeyStroke(KeyEvent.VK_ESCAPE, noModifiers, false);
    InputMap inputMap = dialog.getRootPane().getInputMap(JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT);
    inputMap.put(escapeKey, CANCEL_ACTION_KEY);
    
    Action closeAction = new AbstractAction("Cancel") {

      public void actionPerformed(ActionEvent arg0) {
        dialog.dispose();
      }};
    cancelButton.setAction(closeAction);
    dialog.getRootPane().getActionMap().put(CANCEL_ACTION_KEY, closeAction);
    
  }
}