ActionListener 知道哪个组件触发了动作

Question

我希望有一个动作监听器能够找出源代码，如下面的代码所示。我应该如何实施？

JTextField tf1 = new JTextField();
JTextField tf2 = new JTextField();

ActionListener listener = new ActionListener(){
  @Override
  public void actionPerformed(ActionEvent event){
    if (source == tf1){//how to implement this?
      System.out.println("Textfield 1 updated");
    }
    else if (source == tf2){//how to implement this?
      System.out.println("Textfield 2 updated");
    }
  }
};

tf1.addActionListener(listener);
tf2.addActionListener(listener);

我如何告诉代码，以便我的动作侦听器能够确切地知道哪个 jtextfield 触发了这个动作？

Answer 1

ActionEvent#getSource() returns 发起事件的对象（组件）：

ActionListener listener = new ActionListener() {
  @Override
  public void actionPerformed(ActionEvent event) {
    final Object source = event.getSource();
    if (source.equals(tf1)) {
      System.out.println("Textfield 1 updated");
    }
    else if (source.equals(tf2))
      System.out.println("Textfield 2 updated");
    }
  }
};

ActionListener 知道哪个组件触发了动作

ActionListener knowing which component triggered the action

java

swing

actionlistener

jtextfield