frame_handle_end->set_x0 (pixel_width - (TimeAxisViewItem::GRAB_HANDLE_WIDTH));
frame_handle_end->set_x1 (pixel_width);
frame_handle_end->show();
frame_handle_end->set_x0 (pixel_width - (TimeAxisViewItem::GRAB_HANDLE_WIDTH));
frame_handle_end->set_x1 (pixel_width);
frame_handle_end->show();