Invalid ImageList Index error [Delphi]

Question

This window appear all the time when I change Delphi's tab 'Code' to 'Design'. How can I fix this problem?

Answer 1

I've encountered this exact issue before using Delphi XE8. I found no solution other than restarting the IDE when it happens.

In particular, this happened whenever I would switch between Local Desktop and Remote Desktop. For example, I would start the IDE from locally at the computer itself. Then, I would go to another computer, and open Windows Remote Desktop to that computer, into the same desktop session, and when I went to use the IDE, it would give me the same Invalid ImageList Index error repeatedly.

Since then, I've been using Delphi 10 Seattle, as well as not using Remote Desktop. So I can't say whether this has been fixed yet in later Delphi versions. But if I recall, past attempts to use Delphi 10 Seattle via Remote Desktop have been successful.

Answer 2

i think i found the problem. if look carefully on the error details. the firs row show calling delete on custom image list... so i find out if i delete FMX.ListBox from uses, it will solve my problem. and it worked. so i think the problem is a bug on Firemonkey ListBox unit.