将WindowListener添加到JDialog，并在windowClosed设置布尔值或关闭时的东西。也有一个buttonClicked布尔值，如果他们点击了按钮，它将是真实的，如果他们点击窗口顶部的退出按钮，它将是错误的。
boolean closed;
boolean buttonClicked;
JButton exitbutton;
JDialog dialog;
...
public void actionPerformed(ActionEvent arg0) {
buttonClicked = true;
dialog.dispose();
}
...
dialog.addWindowListener(new WindowListener() {
public void windowActivated(WindowEvent arg0) {
// Do nothing
}
public void windowClosed(WindowEvent arg0) {
closed = true;
if(buttonClicked) {
//They cliked the button to close it.
} else {
// They didn't click the button, they clicked exit in the top right corner of screen.
}
}
public void windowClosing(WindowEvent arg0) {
// Do nothing
}
public void windowDeactivated(WindowEvent arg0) {
// Do nothing
}
public void windowDeiconified(WindowEvent arg0) {
// Do nothing
}
public void windowIconified(WindowEvent arg0) {
// Do nothing
}
public void windowOpened(WindowEvent arg0) {
// Do nothing
}
});
