Re: Java swing JPanel messed up

From:
Daniel Pitts <newsgroup.spamfilter@virtualinfinity.net>
Newsgroups:
comp.lang.java.gui
Date:
Wed, 08 Apr 2009 08:28:26 -0700
Message-ID:
<49dcc231$0$22339$7836cce5@newsrazor.net>
dom.k.black@googlemail.com wrote:

Hi,

I have a prototype, very simple Swing app. It consists of a MainFrame
with a JPanel based component.

I override the JPanel paintComponent() method to plot some data. This
involves quite a few floating point calculations, but not enough to
cause a noticeable delay (ie a small fraction of a second).

It works fine, until I resize the window (causing the JPanel to
resize). Then it messes up, some parts of the plot are correct, some
are displaced upwards in the Y direction. It definitely does a redraw.

I added a button which calls repaint() on the panel. If I press that,
the plot is fine again.

Is there anything I need to do when I resize? Should I call repaint()
after a resize? Is there an onResize event?

Regards

Dom

Make sure you're doing all the drawing on the EDT. If you start a new
Thread at any time, you might be doing things unsafely.

Without an SSCCE, we can't really help you.
(see <http://sscce.org/>)

--
Daniel Pitts' Tech Blog: <http://virtualinfinity.net/wordpress/>

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