DesktopCanvas Size problem

Getting Started
1

Okay the actual code I’m writing is somewhat extensive and I won’t copy it all here but I have narrowed the code down to a few statements that repeat the problem:

I have a window on a Desktop App (2024 2.1 on macOS Tahoe) with a
desktopcanvas on the window named cSubstrate. In the window’s OPEN event I have the following statements:

cSubstrate.Width = 500
cSubstrate.Height = 400
cSubstrate.Backdrop = GrayLightH
cSubstrate.Refresh

Then I have a button on the window that executes the following code:

cSubstrate.Width = 400
cSubstrate.Height = 500
cSubstrate.Refresh
Return

The result is the Canvas redisplays with a width of 400 and a height of 400. There is plenty of room on the window for the added height.

Can someone offer an idea?

thanks

2

Are you sure about the final Height or may it be you just “see” 40000 transparent pixels? :smiley:

3

I’m not seeing this behavior in a simple test:

desktopCanvas1.xojo_binary_project.zip (5.2 KB)

4

What are the dimensions of the GrayLightH image?

5

You suspect the same thing as me. The canvas will probably measure 400x500 pixels, but 40000 of them are transparent. :wink:

6

Thanks so much guys. Bonehead error. it was the size of the backdrop image.

thanks again.