Bug in TListView custom draw item ?

[aradeonas]

Hi,
Today I did work with listview and saw a weird behavior:
I made a simple drag and drop demo for listview:
1- Add 10 item and set all items imageindex=-1.
2- Write dragdrop code for reorder items.
3- Test reorder and it work well.
4- Assign listview custom draw item and run again.
5- Now when I drag an item,item show new image !
6- Delete custom draw item procedure and now everything work fine!

Why?

I attached a sample project for you to test.

[aradeonas]

Somebody please just download sample project and test it for confirm

[Never]

@aradeonas
what is your OS and lazarus v?

[aradeonas]

Windows 8.1
Lazarus 1.2.6
FPC 2.6.2

[Never]

>Assign listview custom draw item and run again.
There is no code in ListCustomDrawItem? you uploaded wrong test project?

[aradeonas]

No,Try drag and drop some item and reorder them,you will see what happen there,moved items get new icon!
That empty ListCustomDrawItem make it wrong,just remove that event from ListView and you will see everything works fine.

[Never]

   lol 

Oh my.....
this is something.....very funny
 i can't stop laughing

[aradeonas]

Oh God,this is a good reason for me to laugh
Maybe we are wrong and I will appreciate any one can tell me what is wrong.

[Never]

i do not now what's wrong  with it lolololol maybe is a feature lolololololol
but as a temporary fix to do your job
add at the start of 

Code: [Select]

procedure TForm1.ListDragDrop(Sender, Source: TObject; X, Y: integer);
......
begin
 List.OnCustomDrawItem:=nil;  or in { ListStartDrag }
end before the end of the procedure
add

Code: [Select]

......................
List.OnCustomDrawItem:=@ListCustomDrawItem;  or in  {  ListEndDrag }
end;


[aradeonas]

Oh,Thank you @Never.
But It's really interesting to me to find out what cause this.

[Never]

from my point of view your code is correct and this is a bug
maybe more experienced users can confirm as well
and report it in the bug tracker

[aradeonas]

Any body else can check it?