.Net Windows Forms ListView OwnerDraw LargeImageList leak

Question

Hello there,

I'm ownerdrawing .Net Windows Forms ListView control and see a very strange bug/behavior when I need to draw an image from the associated LargeImageList.

When the View type is a type where LargeImageList is used (Tile, LargeIcon, etc.), I draw item images from the LargeImageList. At that condition, I see a huge memory increase and when you try to scroll ListView this becomes more obvious as you see a jerky scroll as well. This same thing does not happen when the same code uses SmallImageList which is simply like this :

Image MyImage = this.LargeImageList.Images[MyIndex]; e.Graphics.DrawImage(MyImage,MyLocation);

This is reproducable under XP and 7 according to my tests. Is this a known bug, any workaround?

Regards,

Özden

Answer 1

How are you managing the invalidated drawing area? As you are saying, looks like you are "overdrawing" the control, I mean, drawing even when it is not necessary.

Answer 2

Although I still think this is a bug, I found a workaround. If you draw using ImageList.Draw instead of e.Graphics.DrawImage this problem seems to go away.