Transparent color in Canvas

General
1

How can I set a transparent color in a Canvas. Say I want to show a custom frame and want to see the background see through it? Is that possible? The frame itself is black on white, and a want the white color to be transparant.

2

You can set the forecolor as follow before calling DrawRect.

g.Forecolor = &cff000055

The 55 is a hex value between 0 and 255 that determines the transparency.

3

For Windows builds, make sure you have GDI Plus enabled in the Windows build settings.

4

Mmm… maybe I was not clear. Look at this picture

This is a compiled app. Exactly how it appears in the IDE. GDI+ enabled and g.Forecolor = &cff000055. Transparancy is True.

[Edit] This is a backdrop. My bad. :frowning: That is what I meant. I’m showing a picture and I want the white pixels in the picture to be transparant.

5

Before Xojo / Cocoa, I used the Transparency property. Now…

Read: Picture Support for Transparency.

7

Got it: set both values in the Inspector… that’s all.