TImageEnMView.OnFilter

Declaration

Description

Occurs whenever a frame needs to be displayed. It can be used to implement your own custom filter.

Note:
◼ ShowFrame defaults to True, unless it has been filtered by Filter
◼ OnFilter is called frequently. Ensure your filtering code is quick to avoid slowing user interaction
◼ If you change your filter, you should call Update

Demo

Demos\Multi\Filtering\Filtering.dpr

Examples

procedure TMainForm.IEMViewFilter(Sender: TObject; Index: integer; const Filename: string; var ShowFrame: Boolean);
begin
  // check filename does not exist in our excluded files list list
  if fExcludedFiles.IndexOf( Filename ) >= 0 then
    ShowFrame := False;
end;

procedure TMainForm.ImageEnMView1Filter(Sender: TObject; Index: Integer; const
    Filename: string; var ShowFrame: Boolean);
begin
  // Hide Landscape images
  if ShowFrame and
     chkHideLandscape.checked and
     ( ImageEnMView1.ImageWidth[Index] > ImageEnMView1.ImageHeight[Index] ) then
    ShowFrame := False
  else
  // Hide JPEG images
  if ShowFrame and
     chkHideJPEG.checked and
     (( Lowercase( ExtractFileExt( ImageEnMView1.ImageFilename[Index] )) = '.jpg' ) or
      ( Lowercase( ExtractFileExt( ImageEnMView1.ImageFilename[Index] )) = '.jpeg' )) then
    ShowFrame := False;
end;

TImageEnMView.OnFilter