Out of range error in function TSVGIconImage.SVGIconItem

[luebbe]

I have a strange error which I don't understand.

on a form I have a TSVGIconImage. In FormCreate I assign the imagelist and -index as follows:

  svgArrow.ImageList := dmResources.imlEnabledButtons;
  svgArrow.ImageIndex := cImgRight;

When this image should be painted I receive an "Out of range exception" in

function TSVGIconImage.SVGIconItem: TSVGIconItem;
var
  {$IFDEF D10_3+}
  LVirtualImageList: TVirtualImageList;
  LItem: TVirtualImageListItem;
  {$ENDIF}
  LSVGIconItems: TSVGIconItems;
begin
  Result := nil;
  if FImageList is TSVGIconImageListBase then
  begin
    LSVGIconItems := TSVGIconImageListBase(FImageList).SVGIconItems;
    Result := LSVGIconItems[FImageIndex];
  end;
  {$IFDEF D10_3+}
  if (FImageList is TVirtualImageList) then
  begin
    LVirtualImageList := TVirtualImageList(FImageList);
    if LVirtualImageList.ImageCollection is TSVGIconImageCollection then
    begin
      LSVGIconItems := TSVGIconImageCollection(LVirtualImageList.ImageCollection).SVGIconItems;
      LItem := LVirtualImageList.Images[FImageIndex];
      if Assigned(LItem) then
        Result := LSVGIconItems[LItem.Collectionindex]; <--- Exception here, because LItem.CollectionIndex = -1
    end;
  end;
  {$ENDIF}
end;

because LItem.CollectionIndex = -1

When I initialize the icon with

  svgArrow.ImageList := dmResources.imlEnabledButtons;
  svgArrow.ImageIndex := cImgRight -1;

the icon is painted.

How can it happen that the collectionindex is -1? Is there perhaps a problem with the icon name, because it is similar to a standard property? There must be something to it, because the exception also happens with icons named "Top" or "Right". I only access icons by index, never by name.

[luebbe]

Until now I found out that this is also a very nasty side effect of the combination of gettext translation and SVGIconImageList. At some point it still translates the icon names. When I switch the application's language to English, everything is fine. Have you ever tried what happens, when an icon's name is changed?

This is what I see in the debugger when I put a breakpoint on the exception line: The original item name hasn't changed, but due to some "magic" LItem: TVirtualImageListItem was translated from "stop" to "beenden"

I put a breakpoint here:

procedure TVirtualImageListItem.SetName(const AValue: String);
begin
  FName := AValue;
end;

but this method was never entered.

The solution is again to put a component on gettext's ignore list:

TP_GlobalIgnoreClass(TVirtualImageList);

[luebbe]

Added information to the "Known issues" Wiki page

[pyscripter]

The solution is again to put a component on gettext's ignore list:

TP_GlobalIgnoreClass(TVirtualImageList);

I have been using: TP_GlobalIgnoreClassProperty(TObject,'ImageName');

ImageName should not be translated in any component.

[luebbe]

Should I add this to the Wiki https://github.com/EtheaDev/SVGIconImageList/wiki/Known-issues? I thought it would be better to ignore any property of the List instead of a specific property of any object.

[pyscripter]

I tried to "kill many birds with one stone". ImageName is present in many components (for example CustomButton, MenuItem, Action), and should never be be translated.

[luebbe]

ok, I'll add yours as an alternative solution to the Wiki entry