How can I use my TopComponent as a JFrame?

Question

Netbeans Platform's TopComponents are functionally similar to JFrames in many ways, and are intended to be used so, besides the fact that TopComponent extends JComponent .

However, I'm currently trying to use Docking Frames for my application. I would like to insert a bunch of these in one of my TopComponents, but the control class expects a JFrame as a parameter, and it cannot be instantiated without it. As I said, TopComponent doesn't extend JFrame , so I can't simply cast them, but sadly, they would probably do the trick if I could.

What can I do?

Answer 1

Try using nested JPanel instead.

1. Click on "Design" and right mouse button click and change layout from "Free" to GridBagLayout .
2. Add inner JPanel . I use GridBagConstraints because it's just one line method to ensure "full frame" layout. You can probably use any other layout to do the same.

I try to keep TopComponent as small as possible. All GUI components are in nested JPanels . When you want to test your code without NetBeans platform you'd just add parent JFrame instead of TopComponent .

public MyTopComponent() {
   initComponents();
   panel = new MyPanel();
   //ensures that our panel will be using 100% of our TopComponent
   add(panel, new GridBagConstraints(0, 0, 1, 1, 1.0, 1.0,
       GridBagConstraints.NORTHWEST, 
       GridBagConstraints.BOTH,
       new Insets(0, 0, 0, 0), 0, 0)
   );
}

//this code is generated by GUI editor
// <editor-fold defaultstate="collapsed" desc="Generated Code">                          
private void initComponents() {   
    setLayout(new java.awt.GridBagLayout());
}// </editor-fold>