Reputation: 43
I've faced a problem with Java swing mouse released event which appears seems on mac os java implementation only (there is no such problem on Windows Java).
My configuration: OS X 10.9 Java version: 1.7.0_45, vendor: Oracle Corporation
To repeat this problem run this oracle tutorial demo class
public class MouseEventDemo extends JPanel
implements MouseListener {
BlankArea blankArea;
JTextArea textArea;
static final String NEWLINE = System.getProperty("line.separator");
public static void main(String[] args) {
/* Use an appropriate Look and Feel */
try {
//UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");
//UIManager.setLookAndFeel("com.sun.java.swing.plaf.gtk.GTKLookAndFeel");
UIManager.setLookAndFeel("javax.swing.plaf.metal.MetalLookAndFeel");
} catch (UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
} catch (IllegalAccessException ex) {
ex.printStackTrace();
} catch (InstantiationException ex) {
ex.printStackTrace();
} catch (ClassNotFoundException ex) {
ex.printStackTrace();
}
/* Turn off metal's use of bold fonts */
UIManager.put("swing.boldMetal", Boolean.FALSE);
//Schedule a job for the event dispatch thread:
//creating and showing this application's GUI.
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
/**
* Create the GUI and show it. For thread safety,
* this method should be invoked from the
* event dispatch thread.
*/
private static void createAndShowGUI() {
//Create and set up the window.
JFrame frame = new JFrame("MouseEventDemo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//Create and set up the content pane.
JComponent newContentPane = new MouseEventDemo();
newContentPane.setOpaque(true); //content panes must be opaque
frame.setContentPane(newContentPane);
//Display the window.
frame.pack();
frame.setVisible(true);
}
public MouseEventDemo() {
super(new GridLayout(0,1));
blankArea = new BlankArea(Color.YELLOW);
add(blankArea);
textArea = new JTextArea();
textArea.setEditable(false);
JScrollPane scrollPane = new JScrollPane(textArea);
scrollPane.setVerticalScrollBarPolicy(
JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
scrollPane.setPreferredSize(new Dimension(200, 75));
add(scrollPane);
TextField tf=new TextField(10);
add(tf);
//Register for mouse events on blankArea and the panel.
blankArea.addMouseListener(this);
addMouseListener(this);
setPreferredSize(new Dimension(450, 450));
setBorder(BorderFactory.createEmptyBorder(20,20,20,20));
}
void eventOutput(String eventDescription, MouseEvent e) {
textArea.append(eventDescription + " detected on "
+ e.getComponent().getClass().getName()
+ "." + NEWLINE);
textArea.setCaretPosition(textArea.getDocument().getLength());
}
public void mousePressed(MouseEvent e) {
eventOutput("Mouse pressed (# of clicks: "
+ e.getClickCount() + ")", e);
}
public void mouseReleased(MouseEvent e) {
eventOutput("Mouse released (# of clicks: "
+ e.getClickCount() + ")", e);
}
public void mouseEntered(MouseEvent e) {
eventOutput("Mouse entered", e);
}
public void mouseExited(MouseEvent e) {
eventOutput("Mouse exited", e);
}
public void mouseClicked(MouseEvent e) {
eventOutput("Mouse clicked (# of clicks: "
+ e.getClickCount() + ")", e);
}
public class BlankArea extends JLabel {
Dimension minSize = new Dimension(100, 50);
public BlankArea(Color color) {
setBackground(color);
setOpaque(true);
setBorder(BorderFactory.createLineBorder(Color.black));
}
public Dimension getMinimumSize() {
return minSize;
}
public Dimension getPreferredSize() {
return minSize;
}
}
}
"Mouse Release" event for BlankArea is fired perfectly in all cases except the following:
Thanks for your help in advance.
EDITED: I've added a TextField at the bottom of main frame. Now, if repeat all case steps described above, but release mouse exactly on TextField the "mouse_released" event is fired, but still not on TextArea.
Upvotes: 4
Views: 1003
Reputation: 205785
The observed behavior also prevails using Java 6 on Mac OS X. Note that getComponent()
"Returns the originator of the event." In general, your program should not rely on anomalous, platform-specific results. As the Windows behavior is not documented, your actual goal may inform a more reliable approach.
Correction: This is a regression in 1.7.0_45
on Mac OS X, examined in JDK-8013475
.
Upvotes: 1