Treeview background image

[=?Utf-8?B?UGF0cmlja1M=?=]

I'd like to be able to give a treeview in my application a nice smooth
gradient as a background image, but I'm having trouble doing this. Webpages
that I've seen so far seem to suggest using the BackgroundImage property, but
this does not seem to work. I'm using C# Express 2008.

Does anybody here have any solutions?

[=?Utf-8?B?RnJhbmsgVXJheQ==?=]

RE: Treeview background image

I am using UltraTree from Infragistics,
this works perfect.

Best regards
Frank

"PatrickS" wrote:

I'd like to be able to give a treeview in my application a nice smooth
gradient as a background image, but I'm having trouble doing this. Webpages
that I've seen so far seem to suggest using the BackgroundImage property, but
this does not seem to work. I'm using C# Express 2008.
>
Does anybody here have any solutions?

[Peter Duniho]

Re: Treeview background image

On Tue, 22 Jul 2008 03:34:00 -0700, PatrickS
<msdn_newsgroup s001@_removetex tplusunderscore s_seurre.com.wr ote:

I'd like to be able to give a treeview in my application a nice smooth
gradient as a background image, but I'm having trouble doing this.
Webpages
that I've seen so far seem to suggest using the BackgroundImage
property, but
this does not seem to work. I'm using C# Express 2008.
>
Does anybody here have any solutions?

Good question. :) BackgroundImage is public, but MSDN says it's for
"framework use only" and I was unable to see any effect when setting it,
nor was I able to get the OnPaint() or OnPaintBackgrou nd() methods to be
called when I tried sub-classing TreeView. They seem to just be
completely disabled.

However, I was successful in overriding WndProc(), watching for the
WM_PAINT or WM_ERASEBKGND messages and drawing a background image there (I
added a public property to allow me to set the Image). If handling
WM_PAINT, you can do it before calling the base.WndProc(), and if handling
WM_ERASEBKGND, you can do it after calling base.WndProc(). Either
approach seemed to work.

I understand why the TreeView control might not actually use OnPaint() and
OnPaintBackgrou nd() itself, but I was surprised that it doesn't even call
those methods at all. That certainly seems odd to me. Looks like you
need to go "old-school" to do this (and a warning: there's always a chance
that doing so isn't going to work perfectly...I didn't test that option
thoroughly).

Pete

[=?Utf-8?B?UGF0cmlja1M=?=]

RE: Treeview background image

Unfortunately I don't believe that spending the sort of money they appear to
be asking for is an option.

(and would be like taking a sledgehammer to a nut given that all I want to
do that's out of the ordinary at this stage is set the background image and
they only seem to be selling an entire suite of controls)

"Frank Uray" wrote:

I am using UltraTree from Infragistics,
this works perfect.
>
Best regards
Frank
>
"PatrickS" wrote:
>

I'd like to be able to give a treeview in my application a nice smooth
gradient as a background image, but I'm having trouble doing this. Webpages
that I've seen so far seem to suggest using the BackgroundImage property, but
this does not seem to work. I'm using C# Express 2008.

Does anybody here have any solutions?

[=?Utf-8?B?UGF0cmlja1M=?=]

Re: Treeview background image

It seems that the following line of code will allow the BackgroundImage value
to be respected:

this.SetStyle(C ontrolStyles.Us erPaint, true);

However now the nodes are not being displayed. It's as if the background is
actually being displayed over them. I guess a bit of further investigation
would not amiss. Thank you for the tip though.

"Peter Duniho" wrote:

On Tue, 22 Jul 2008 03:34:00 -0700, PatrickS
<msdn_newsgroup s001@_removetex tplusunderscore s_seurre.com.wr ote:
>

I'd like to be able to give a treeview in my application a nice smooth
gradient as a background image, but I'm having trouble doing this.
Webpages
that I've seen so far seem to suggest using the BackgroundImage
property, but
this does not seem to work. I'm using C# Express 2008.

Does anybody here have any solutions?

>
Good question. :) BackgroundImage is public, but MSDN says it's for
"framework use only" and I was unable to see any effect when setting it,
nor was I able to get the OnPaint() or OnPaintBackgrou nd() methods to be
called when I tried sub-classing TreeView. They seem to just be
completely disabled.
>
However, I was successful in overriding WndProc(), watching for the
WM_PAINT or WM_ERASEBKGND messages and drawing a background image there (I
added a public property to allow me to set the Image). If handling
WM_PAINT, you can do it before calling the base.WndProc(), and if handling
WM_ERASEBKGND, you can do it after calling base.WndProc(). Either
approach seemed to work.
>
I understand why the TreeView control might not actually use OnPaint() and
OnPaintBackgrou nd() itself, but I was surprised that it doesn't even call
those methods at all. That certainly seems odd to me. Looks like you
need to go "old-school" to do this (and a warning: there's always a chance
that doing so isn't going to work perfectly...I didn't test that option
thoroughly).
>
Pete
>