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Making your class an event source in Java

I'm making a custom button in Java that has two states, mousePressed, and mouseReleased. At the same time, if I wanted to reuse this button, so that other event listeners can register with it, are these the appropriate steps I should do (This is a hw assignment so although a JButton could be used, I think we are trying to show that we can create our own Button to act like JButton:

  • override addActionListener(ActionListener action)
  • override removeActionListener(ActionListener action)
  • have a private variable like List list = new List () to keep track of when events get added and some sort of function with for loop to run all the actions. Here is what I have so far:

    public class CustomButton { public static void main(String[] args) { Eve开发者_Python百科ntQueue.invokeLater(new Runnable() { public void run() { CustomButtonFrame frame = new CustomButtonFrame(); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.setVisible(true); } }); }

        public void addActionListener(ActionListener al)
        {
            listenerList.add(al);
        }
    
        public void removeActionListener(ActionListener al)
        {
            listenerList.remove(al);
        }
    
        private void notifyListeners()
        {
            for (ActionListener action : listenerList) {
                action.actionPerfomed();
            }
        }
    
        List<ActionListener> listenerList = new ArrayList<ActionListener>();
    }
    

I'm getting the compile errors: line 38: reference to List is ambiguous, both class java.util.List in java.util and class java.awt.List in java.awt match List listenerList = new ArrayList();

and line 34: cannot find symbol, method actionPerfomed() in interface java.awt.event.ActionListener action.actionPerformed();


No, completely not!

A JButton has everything you need. Just add your own listener to the button. Don't override something. Just like this:

public class MyButton extends JButton implements MouseListener // maybe you want to add other listeners... separate them with comma's.
{
     public MyButton(String caption)
     {
         super(caption);
         addMouseListener(this);
     }

     // implement your listener methods here

}


I'm making a custom button in Java that has two states, mousePressed, and mouseReleased

Maybe you should be using a JToggleButton.

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