we tracked this problem to the reshape() method in heavyweight components, which
goes into native code and *always* erases the component with the background
color. This causes most of the flickering that we have seen when trying to
combine heavyweight and lightweight.
Whenever the component moves it gets its background erased.
Please go and vote for bug 4060388, which has been on the bug parade since June
20, 1997!
good luck,
Ben Hinkle
> -----Original Message-----
> From: Ralph E. LaChance [mailto:[EMAIL PROTECTED]]
> Sent: Wednesday, June 23, 1999 4:11 PM
> To: [EMAIL PROTECTED]
> Subject: [JAVA2D] 2d drawing on Canvas on JInternalFrame
>
>
> Hi,
>
> We prototyped our Java2D application drawing 2D thingys
> on a (subclass of) canvas which in turn lives on a subclass
> of awt Frame. We double-bufferall painting to the canvas
> to get nice clean painting. In this config, all is fine so far.
>
> Now we're starting to (try to) swing it so the drawing canvas
> lives on a subclass of JInternalFrame, which itself lives
> on a JDesktopPane inside a JFrame. Seems like a reasonable
> approach: for this app, it makes sense to have multiple,
> separate, drawings active on the screen at once.
>
> Horrors in a hand basket!
>
> Dragging the internal frame causes the drawing to *badly*
> flicker; and re sizing the internal frame does so too.
>
> Now I think we understand what all's going on --
>
> a) the first because lightweight frames maybe don't get
> bitblt'd by the underlying OS, instead we're passed
> repeated Paint msg's during dragging
> b) the 2nd because we're ignoring (for the minute) the
> clip area passed to paint - we know we should only
> repaint according to the hints supplied... later.
>
> Is this the way its gonna be? That is, should we abandon
> the internal frames approach for the foreseeable?
> (i.e. if it didn't change in jdk1.2.2, we're gonna change back)
>
> Tia,
> -Ralph
>
> ==============================================================
> =============
> To unsubscribe, send email to [EMAIL PROTECTED] and
> include in the body
> of the message "signoff JAVA2D-INTEREST". For general help,
> send email to
> [EMAIL PROTECTED] and include in the body of the message "help".
>
===========================================================================
To unsubscribe, send email to [EMAIL PROTECTED] and include in the body
of the message "signoff JAVA2D-INTEREST". For general help, send email to
[EMAIL PROTECTED] and include in the body of the message "help".
