Delphi - Drag & Drop with ListView

Question

Good evening :-)!

I have this code to use Drag & Drop method for files:

TForm1 = class(TForm)
...
public
    pr         


        

Answer 1

You've called DragAcceptFiles for the ListView, so Windows sends the WM_DROPFILES to your ListView and not to your Form. You have to catch the WM_DROPFILES message from the ListView.

  private
    FOrgListViewWndProc: TWndMethod;
    procedure ListViewWndProc(var Msg: TMessage);
  // ...
  end;

procedure TForm1.FormCreate(Sender: TObject);
begin
  // Redirect the ListView's WindowProc to ListViewWndProc
  FOrgListViewWndProc := ListView1.WindowProc;
  ListView1.WindowProc := ListViewWndProc;

  DragAcceptFiles(ListView1.Handle, True);
end;

procedure TForm1.ListViewWndProc(var Msg: TMessage);
begin
  // Catch the WM_DROPFILES message, and call the original ListView WindowProc 
  // for all other messages.
  case Msg.Msg of
    WM_DROPFILES:
      DropFiles(Msg);
  else
    if Assigned(FOrgListViewWndProc) then
      FOrgListViewWndProc(Msg);
  end;
end;

Answer 2

Your problem is, you're registering the list view window as a drop target, but handling the WM_DROPFILES message in the form class. The message is sent to the list view control, you should handle the message there.