Adding textfield to Graphics in java

问题:

Does anyone know how to add JTextField into Graphics name bufferstrategy.getDrawGraphics? Tryed to pain it into graphics, something like this:

private JTextField Input = new JTextField();
BufferStrategy bs = getBufferStrategy();

if (bs == null) {
    createBufferStrategy(3);
    return;
}

final Graphics gCommands = bs.getDrawGraphics();
Graphics gCC = bs.getDrawGraphics();
Input.requestFocus();
Input.paint(gCC);
Input.setBounds(800,250, 350,20);
Input.setBorder(BorderFactory.createLineBorder(Color.BLACK, 0));
Input.setEditable(true);
Input.setBackground(getBackground());
Input.setForeground(getForeground());
Input.addKeyListener(key);

But, eventhough it displayed, I could not edit it. Even the Input.setBounds(800,250, 350,20) did not work. This method that is written above, is being called inside a gameloop. Can anyone help me?

回答1:

Painting a component on a Graphics won't make it a "live" component. Components need to be added to a valid container that is attached to a native peer before they become live.

At the moment, the only thing you are doing is producing a "rubber stamp"/image of the component on the surface of the graphics context.

There are some tricks to this, as the painting process expects that the component is attached to a valid, native peer.

First, you must prepare the field...

Input.setBounds(800,250, 350,20);
Input.setBorder(BorderFactory.createLineBorder(Color.BLACK, 0));
Input.setEditable(true);
Input.setBackground(getBackground());
Input.setForeground(getForeground());

Then you need to paint it. The field will not automatically repaint, again, this has to do with the field not been attached to a native peer...

Input.printAll(gCC);

If you want a life component, you are going to have to add the component to the container. This may be problematic when using a buffer strategy...

Swing components are already double buffered.