Java中的KeyBindings在重新生成组件后停止工作

时间:2013-02-23 01:52:19

标签: key-bindings

我的JPanel的KeyBindings工作正常,直到我从JFrame中删除JPanel,创建一个新的JPanel对象,然后将其添加到JFrame。

KeyBinding方法再次在新的JPanel对象上运行,但Keys不做任何事情。

以下是我用来展示问题的两个课程:

public class KeyBindingsTester {

    static JFrame jf;
    static KeyBindingPanel kp;

public static void main(String[] args){
    new KeyBindingsTester(); 
}
public KeyBindingsTester(){

    jf = new JFrame();
    kp = new KeyBindingPanel();

    jf.add(kp, BorderLayout.CENTER);
    jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    jf.setVisible(true);
}
public static void reset(){
    jf.remove(kp);
    kp = new KeyBindingPanel();
    jf.add(kp,BorderLayout.CENTER);
            jf.setVisible(true);
}
}

---------和小组:

public class KeyBindingPanel extends JPanel{

public KeyBindingPanel(){
    setUpKeyBindings();
    System.out.println("Keybindings set up");
}
public void setUpKeyBindings(){

    addKeyBinding("B");
    addKeyBinding("R");
}
public void addKeyBinding(String key){

    getInputMap().put(KeyStroke.getKeyStroke(key), key);
    getActionMap().put(key, new KeyBindingAction(key));
}

public class KeyBindingAction extends AbstractAction{

    String action;
    public KeyBindingAction(String actionName){
    action = actionName;
}
public void actionPerformed(ActionEvent e){
    if(action.equals("R")){
        KeyBindingsTester.reset();
    }
    if(action.equals("B")){
        System.out.println("BBB");
    }
}
}
}

1 个答案:

答案 0 :(得分:0)

问题在于焦点不在于JPanel。

更改此内容:getInputMap()。put(KeyStroke.getKeyStroke(key),key);
对此:getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW).put(KeyStroke.getKeyStroke(key),key);