Question

java图形设计，窗口阻塞的问题。

打开一个java窗口（原JFrame），里面有个按钮，点击后出现另一个窗口（新JFrame），如何使得原窗口处于阻塞的状态（即新窗口才是当前活动窗口，要想操作原窗口，就必须关闭新窗口）？

Answer 1

在 Swing 中只有 JDialog 可以设置为 Modal 窗体，
其方法可以在构造函数（例如“JDialog(Frame owner, boolean modal)”）中传参数，
也可以用 setModal(boolean b) 方法设定，
这个方法是从 Dialog 类继承的。
在 JFrame 类中，无法通过如 JDialog 的方法设置 Modal 窗体，
在 CSDN 有朋友尝试通过在 windowDeiconified() 时
requestFocus() 来模拟 Modal 窗体，代码如下：

public class MyModalFrame extends JFrame implements WindowListener ...{
PRivate JFrame frame = null;
private boolean modal = false;
private String title = null;

public MyModalFrame() ...{
this(null, false);
}

public MyModalFrame(JFrame frame) ...{
this(frame, false);
}

public MyModalFrame(JFrame frame, boolean modal) ...{
this(frame, modal, "");
}

public MyModalFrame(JFrame frame, boolean modal, String title) ...{
super(title);
this.frame = frame;
this.modal = modal;
this.title = title;
this.init();
}

private void init() ...{
if(modal)
frame.setEnabled(false);
this.addWindowListener(this);
}

public void windowOpened(WindowEvent windowEvent) ...{
}

public void windowClosing(WindowEvent windowEvent) ...{
if(modal)
frame.setEnabled(true);
}

public void windowClosed(WindowEvent windowEvent) ...{
}

public void windowIconified(WindowEvent windowEvent) ...{
}

public void windowDeiconified(WindowEvent windowEvent) ...{
}

public void windowActivated(WindowEvent windowEvent) ...{
}

public void windowDeactivated(WindowEvent windowEvent) ...{
if(modal)
this.requestFocus();
}
}