如何在涉及 ActionListener 的另一个类中启用按钮

Question

I have this code that I am referencing in Java Eclipse:

public class ClassWithButton extends JFrame{
    private final JPanel Your_Panel_name;

    public void enableButtons() {
    for (Component c : Your_Panel_name.getComponents()) {
      if (c instanceof JButton) 
         c.setEnabled(true);
     }
  }
}

Then there is a class which implements ActionListener.java

public class ActionListenerImpl implements ActionListener{
    public void actionPerformed(ActionEvent e){

    }
}

I have a button in a class that extends JFrame and I have a panel in which I disabled two buttons on it. I have another class that extends ActionListener, when I press another button on the panel, I want the 2 disabled buttons to be enabled, how would I go about doing so?

Answer 1

I would suggest you define your own Listener class to achieve your goal.

First, define a Listener class.

public interface ButtonEnabledListener {
    void buttonEnabled(boolean isEnabled);
}

Second, implement this Listener for your JFrame or JPanel class.

public YourJPanel extends JPanel implements ButtonEnabledListener {
    void buttonEnabled(boolean isEnabled) {
        for (JButton button : buttons) {
            button.setEnabled(isEnabled);
        }
    }
}

Last, in another class, pass in your frame or panel and fire the event. Since your class implements ActionListener, so fire the event in the implemented method.

public AnotherClass implements ActionListener {
    JButton yourButton;
    ButtonEnabledListener listener;
    public AnotherClass(ButtonEnabledListener yourPanel) {
       yourButton = new JButton("enable buttons in my panel");
       yourButton.addActionListener(this);
       listener = yourPanel;
    }
    public void actionPerformed(ActionEvent e) {
        listener.buttonEnabled(true);                    
    }
}

Answer 2

With the code you've given, here's a quick example of how the reference works, but this is not the way I would implement it.

public class ClassWithButton extends JFrame{
    private final JPanel Your_Panel_name;
    ActionListenerImpl act;
    JButton otherButton;
    public ClassWithButton()
    {
        act = new ActionListenerImpl(this);
        otherButton = new JButton("Click to enable");
        otherButton.addActionListener(act);
    }
    public void enableButtons() {
        for (Component c : Your_Panel_name.getComponents()) {
            if (c instanceof JButton) 
                c.setEnabled(true);
        }
    }
}

public class ActionListenerImpl implements ActionListener{
    ClassWithButton b;
    public ActionListenerImpl(ClassWithButton b)
    {
        this.b = b;
    }
    public void actionPerformed(ActionEvent e){
        b.enableButtons();
    }
}