Question

我正在尝试将JDialog保持在JFrame内部，无论JFrame是移动还是调整大小。

基本上，我有一个类（这不是真正的代码，只是一个例子）

 import javax.swing.*;        
import javax.swing.event.AncestorEvent;
import javax.swing.event.AncestorListener;
import java.awt.event.ComponentAdapter;
import java.awt.event.ComponentEvent;
import java.awt.Dimension;
import java.awt.Color;

public class HelloWorldSwing extends ComponentAdapter implements   AncestorListener {


private JDialog dialog;

private JFrame frame;

@Override
public void componentResized( ComponentEvent event ) {
    //This value does not hcange when dragged from the left or right
    System.err.println( " Location " + frame.getLocationOnScreen() );
    recenter();
}    

@Override
public void ancestorAdded( AncestorEvent evt ) {

}

@Override
public void ancestorRemoved( AncestorEvent evt ) {

}

@Override
public void ancestorMoved( AncestorEvent evt ) {
    //This value does not hcange when dragged from the left or right
    System.err.println( " Location " + frame.getLocationOnScreen() );
    recenter();
}

private void recenter() {
    dialog.setLocationRelativeTo( frame.getRootPane() );
}


/**
 * Create the GUI and show it.  For thread safety,
 * this method should be invoked from the
 * event-dispatching thread.
 */
private void createAndShowGUI() {
    //Create and set up the window.
    frame = new JFrame("HelloWorldSwing");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.getRootPane().addAncestorListener( this );
    frame.getRootPane().setBackground( Color.WHITE );        
    frame.addComponentListener( this );
    frame.setMinimumSize( new Dimension( 500, 500 ) );
    frame.setMaximumSize( new Dimension( 500, 500 ) );

    dialog = new JDialog();
    dialog.setResizable( true );
    dialog.setAlwaysOnTop( true );
    dialog.setVisible( true );
    dialog.setMaximumSize( new Dimension( 200, 200 ) );
    dialog.setMinimumSize( new Dimension( 200, 200 ) );

    //Display the window.
    frame.pack();
    frame.setVisible(true);
}

public static void main(String[] args) {
    //Schedule a job for the event-dispatching thread:
    //creating and showing this application's GUI.
    javax.swing.SwingUtilities.invokeLater(new Runnable() {
        public void run() {
            HelloWorldSwing swing = new HelloWorldSwing();
            swing.createAndShowGUI();
        }
    });
}
}

当从左侧或顶部调整JFrame的大小时，屏幕上的位置会发生变化，但getLocationOnScreen（）不会更改其结果。似乎getLocationOnScreen应该因左上角由于调整大小而发生变化而改变。

我错过了什么？感谢。

更新::

此代码似乎在Windows上正常运行，但在Fedora 21，java 7上无法正常运行

调整大小后屏幕上的Java Swing位置

0 个答案: