Question

I have function dodaj(); in JFrame, and in this JFrame i have JPanel.
To use Buttons from JPanel i am using ActionListener. But when someone click on button I wanna call function dodaj(); from JFrame.
If I have ActionLIstener in JFrame i can use this.dodaj();, but i have action listener on JPanel, with is composition od JFrame.
How could i call dodaj(); (JFrame function) from ActionListener with is on JPanel?

Thanks for reading it and sorry for my bad english.

Answer 1

You don’t mention it, but are your JFrame and JPanels both classes, and so your problem is that you want to call a method from one class in another class? If so, the key is to get a reference to the JFrame class and pass it into the JPanel class via a constructor or method parameter.

For example:

class MyFrame extends JFrame {
   private MyPanel myPanel;

   public MyFrame() {
      myPanel = new MyPanel(this);
   }

   public void frameMethod() {
      System.out.println("in JFrame's frameMethod");
   }

}

class MyPanel extends JPanel {
   private MyFrame myFrame;
   private JButton someButton = new JButton("Button");

   public MyPanel(final MyFrame myFrame) {
      this.myFrame = myFrame;

      someButton.addActionListener(new ActionListener() {
         @Override
         public void actionPerformed(ActionEvent arg0) {
            myFrame.frameMethod();
         }
      });
   }  
}

As an aside, I don’t recommend extending JFrame or JPanel without good reason such as the need to override methods.