Drag and drop into other program

I would like to create an application for drag and drop to take a file into other application. For example, in my python window I would like take file and drop it in windows or photoshop. Is it possible in Python and need I use pywin32? For the moment I didn't find any information about this problem or just into window program path Thank you in advance

Solution

I do not have Windows, but from what I remember, you'll need to have a window's handle (either for the shell Window or for some graphical one e.g. WinForms or others). Then try to check the WM_DROPFILES message or better, ole2.h's RegisterDragDrop and via pDropTarget try to retrieve the sent path.

For WM_DROPFILES you can take an inspiration from SDL2's codebase in SDL_windowsevents.c

    case WM_DROPFILES:
        {
            UINT i;
            HDROP drop = (HDROP) wParam;
            UINT count = DragQueryFile(drop, 0xFFFFFFFF, NULL, 0);
            for (i = 0; i < count; ++i) {
                SDL_bool isstack;
                UINT size = DragQueryFile(drop, i, NULL, 0) + 1;
                LPTSTR buffer = SDL_small_alloc(TCHAR, size, &isstack);
                if (buffer) {
                    if (DragQueryFile(drop, i, buffer, size)) {
                        char *file = WIN_StringToUTF8(buffer);
                        SDL_SendDropFile(data->window, file);
                        SDL_free(file);
                    }
                    SDL_small_free(buffer, isstack);
                }
            }
            SDL_SendDropComplete(data->window);
            DragFinish(drop);
            return 0;
        }
        break;

which uses WIN_WindowProc() in this manner:

Initialize WNDCLASSEX struct:

WNDCLASSEX wcex;
// fill its members and this one for event handling:
wcex.lpfnWndProc = WIN_WindowProc;

then register it with RegisterClassEx(&wcex).

Of course, that's just C/C++ code. You'll either need to find translated or otherwise linked members of the libraries in pywin32 or use something that can access the libraries in a way you need, such as ctypes or Cython.

Other resources: