+ struct queuelike *const ql = user_data;
+ struct ql_drag_begin_state qdbs[1];
+ GdkPixmap *icon;
+
+ //fprintf(stderr, "drag-begin\n");
+ memset(qdbs, 0, sizeof *qdbs);
+ qdbs->ql = ql;
+ /* Find out how many rows there are */
+ if(!(qdbs->rows = gtk_tree_selection_count_selected_rows(ql->selection)))
+ return; /* doesn't make sense */
+ /* Generate a pixmap for each row */
+ qdbs->pixmaps = xcalloc(qdbs->rows, sizeof *qdbs->pixmaps);
+ gtk_tree_selection_selected_foreach(ql->selection,
+ ql_drag_make_row_pixmaps,
+ qdbs);
+ /* Determine the size of the final icon */
+ int height = 0, width = 0;
+ for(int n = 0; n < qdbs->rows; ++n) {
+ int pxw, pxh;
+ gdk_drawable_get_size(qdbs->pixmaps[n], &pxw, &pxh);
+ if(pxw > width)
+ width = pxw;
+ height += pxh;
+ }
+ if(!width || !height)
+ return; /* doesn't make sense */
+ /* Construct the icon */
+ icon = gdk_pixmap_new(qdbs->pixmaps[0], width, height, -1);
+ GdkGC *gc = gdk_gc_new(icon);
+ gdk_gc_set_colormap(gc, gtk_widget_get_colormap(ql->view));
+ int y = 0;
+ for(int n = 0; n < qdbs->rows; ++n) {
+ int pxw, pxh;
+ gdk_drawable_get_size(qdbs->pixmaps[n], &pxw, &pxh);
+ gdk_draw_drawable(icon,
+ gc,
+ qdbs->pixmaps[n],
+ 0, 0, /* source coords */
+ 0, y, /* dest coords */
+ pxw, pxh); /* size */
+ y += pxh;
+ }
+ // TODO scale down a bit, the resulting icons are currently a bit on the
+ // large side.
+ gtk_drag_source_set_icon(ql->view,
+ gtk_widget_get_colormap(ql->view),
+ icon,
+ NULL);