On http://wiki.freepascal.org/VirtualTreeview_Example_for_Lazarus there is the following example procedure:
------------------------------------------------ procedure TForm1.Button1Click(Sender: TObject); Var Data: PTreeData; XNode: PVirtualNode; Rand: Integer; Begin Randomize; Rand := Random(99); XNode:=VST.AddChild(nil); if VST.AbsoluteIndex(XNode) > -1 then Begin Data := VST.GetNodeData(Xnode); Data^.Column0:= 'One ' + IntToStr(Rand); Data^.Column1:= 'Two ' + IntToStr(Rand + 10); Data^.Column2:= 'Three ' + IntToStr(Rand - 10); End; End; ------------------------------------------------ Can someone explain what the line if VST.AbsoluteIndex(XNode) > -1 then actually means? The method AbsoluteIndex gives back a Cardinal so how can it be less than 0? Therefore the if statement is completely useless because it is always true. BTW: I was pointed to this because Lazarus (or FPC?) showed me a compiling message that this line will cause a type convertion to 64 bit (well done!). -- _______________________________________________ Lazarus mailing list [email protected] http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
