One action listener, two JButtons

问题

I have two JButtons called "Left" and "Right". The "Left" button moves a rectangle object to the left and the "Right" button moves it to the right. I have one ActionListener in the class that acts as the listener for when either button is clicked. However I want different actions to happen when each are clicked. How can I distinguish, in the ActionListener, between which was clicked?

回答1:

Set actionCommand to each of the button.

// Set the action commands to both the buttons.

 btnOne.setActionCommand("1");
 btnTwo.setActionCommand("2");

public void actionPerformed(ActionEvent e) {
 int action = Integer.parseInt(e.getActionCommand());

 switch(action) {
 case 1:
         //doSomething
         break;
 case 2: 
         // doSomething;
         break;
 }
}

UPDATE:

public class JBtnExample {
    public static void main(String[] args) {
        JButton btnOne = new JButton();
        JButton btnTwo = new JButton();

        ActionClass actionEvent = new ActionClass();

        btnOne.addActionListener(actionEvent);
                btnTwo.addActionListener(actionEvent);

        btnOne.setActionCommand("1");
        btnTwo.setActionCommand("2");
    }
} 

class ActionClass implements ActionListener {

    @Override
    public void actionPerformed(ActionEvent e) {
        int action = Integer.parseInt(e.getActionCommand());
        switch (action) {
        case 1:
            // DOSomething
            break;
        case 2:
            // DOSomething
            break;                          
        default:
            break;
        }
    }
}

回答2:

Quite easy with the getSource() method available to ActionEvent:

JButton leftButton, rightButton;

public void actionPerformed(ActionEvent e) {
  Object src = e.getSource();

  if (src == leftButton) {

  }
  else if (src == rightButton) {

  }
}

来源：https://stackoverflow.com/questions/14443259/one-action-listener-two-jbuttons

标签

java

swing

awt

jbutton

actionlistener