I`m using the pictureViewer sample of Alex Restrepo and unfortunately i cannot find details about him anymore to see the changes from RS to xojo.
I put the project on a dropbox and can be found here pictureViewer and it seems that the code from the computed property it creates error .
I did tested different samples with that computed property and some have same error.
Thanks again and hope that the project will help fixing the error. I will try to debug that and if in case i find a resolution for that i will post it here for helping others that use same code .
If the code Alex posted (which I assume was from long ago)… refers to the GRAPHIC object of a CANVAS control OUTSIDE of the Canvas Paint event… this most likely is the root of the issue. That was problematic then, and not allowed now.
IF that is the issue, it will require redesign and coding of the functions involved.
This is just a guess, since it is a pictureviewer, but I have not the time right now to investigate the code.
take a look into property (change visible to mevisible) and in PictureViewer.PictureCanvas.Paint (change if not visible then Return into if not mevisible then Return