为什么没有调用windowClosed?

vic*_*icd 7 java user-interface swing

我有一个问题,为什么在我的测试代码中没有调用"windowClosed"方法如下,

import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

import javax.swing.JFrame;

public class Tmp {

    class TFrame extends JFrame{
        private static final long serialVersionUID = -5729542298504858399L;

        public TFrame() {
            setTitle("title");
            setSize(300, 300);
        }
    }


    public static void main(String[] args) {
        final TFrame t = new Tmp().new TFrame();
        t.addWindowStateListener(new WindowAdapter() {
            @Override
            public void windowStateChanged(WindowEvent e) {
                super.windowStateChanged(e);
                System.out.println(e.getOldState() + "<-old new->" + e.getNewState());
            }
        });
        t.addWindowListener(new WindowAdapter() {

            @Override
            public void windowClosed(WindowEvent e) {
                super.windowClosed(e);
                System.out.println(e.getID() + "closed " + e.getNewState());
            }

            @Override
            public void windowClosing(WindowEvent e) {
                super.windowClosing(e);
                System.out.println(e.getID() + "closing" + e.getNewState());
            }
        });
        t.setVisible(true);
    }
}
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如果我写语句setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE)或显式调用dispose()到TFrame,windowClosed()将被调用.

是否有人可以更详细地解释它,我很困惑为windowClosed()编写监听器的属性方式,提前感谢.

//////////////////根据Dan //////////////的一些导游更新

import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

import javax.swing.JFrame;
import javax.swing.JOptionPane;

public class Tmp {

    class TFrame extends JFrame {
        // ignored .....
        t.addWindowListener(new WindowAdapter() {

            @Override
            public void windowClosed(WindowEvent e) {
                super.windowClosed(e);
                System.out.println(e.getID() + "closed " + e.getNewState());
            }

            @Override
            public void windowClosing(WindowEvent e) {
                super.windowClosing(e);
                System.out.println(e.getID() + "closing" + e.getNewState());
                int quit = JOptionPane.showConfirmDialog(t, "Are you sure to quit?");
                if(quit == JOptionPane.YES_OPTION){
                    t.dispose();
                }
                else if (quit == JOptionPane.NO_OPTION){
                    t.setVisible(false);
                }
            }
        });
        t.setVisible(true);
        t.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
    }
}
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Dan*_* D. 7

setDefaultCloseOperationis 的默认值HIDE_ON_CLOSE.有了这个,窗口没有关闭,它只是隐藏.

将值更改为其他值,您可以将其实际关闭而不是仅隐藏它,因此将触发事件.

  • 我不得不说,我不喜欢JRE在这里的命名.HIDE_ON_CLOSE意味着关闭窗口会隐藏窗口.也就是说你关闭了窗口.也就是说你通常会期望windowClosed被解雇!似乎非常模糊,只有DISPOSE_ON_CLOSE会触发windowClosed.它记录在某个地方,但命名肯定是模棱两可的. (2认同)