Add a JPanel to a JPanel...

[Andreas Beresko]

Hi,

I got followning problem: i have visible JPanel on the screen. When i click
on it, a contet menu appears, where I can coose "add another panel".
This calls a method paintNewPanel() and should add a new visible panel on my
panel. Code:

public void paintNewPanel(JPanel drawArea){ //is the JPanel which captures
the mouseclick an which should contain the new panel

JPanel panel = new JPanel();
panel.setBackground(Color.gray);
drawArea.add(panel);
panel.setBounds(0,0,100,100);

}

Problem: the new Panel isn't visible. I tried to call drawArea.repaint,
invalidate ... but nothing happens. Where's my fault?

best regarda Andreas

 

[Tor Iver Wilhelmsen]

Problem: the new Panel isn't visible. I tried to call drawArea.repaint,
invalidate ... but nothing happens. Where's my fault?

1) Are you sure drawArea has a null layout? Swing/AWT will laugh
heartlessly at your setBounds() otherwise.

2) Make sure the JPanel is opaque. I think they are by default though.

 

[Andreas Beresko]

Thanks for answer, but...

Problem: the new Panel isn't visible. I tried to call drawArea.repaint,
invalidate ... but nothing happens. Where's my fault?

1) Are you sure drawArea has a null layout? Swing/AWT will laugh
heartlessly at your setBounds() otherwise.

..... I'm sure it's null layout...

2) Make sure the JPanel is opaque. I think they are by default though.

.... when I set the first Panel to nonopaque I see my secon Panel I lay on
it, BUT: i want to add some
Mouse listeners to my second Panel and so it has to be in front of my first
(background panel)...

any other suggestion?

 

[Andrew Thompson]

I got followning problem:

...you seem to have a 'multi-posting' problem
as well. See my answer on c.l.j.gui.

 

[Andrew Thompson]

any other suggestion?

<http://www.physci.org/codes/sscce.jsp>

[ It sounds like you are doing a number of
things wrong, but it is difficult to say
without a complete example.

And given it is a GUI problem, it might be
best to post it to the thread on c.l.j.gui!

(..both me and ak read that group as well) ]

 

[Tor Iver Wilhelmsen]

... when I set the first Panel to nonopaque I see my secon Panel I lay on
it,

This seems to indicate that your "first" and "second" panels are in
the same container, not the second inside the first. Perhaps also that
what you think of as the background panel gets added after the "second
panel".

BUT: i want to add some Mouse listeners to my second Panel and so it
has to be in front of my first (background panel)...

This should be automatic as long as

You can try rearranging them by adjusting z-order.

 

[Liz]

You mean panel.setOpaque(false); nonopaque == nullPointer;