+/** @brief Called when a drag moves within a candidate destination
+ * @param w Destination widget
+ * @param dc Drag context
+ * @param x Current pointer location
+ * @param y Current pointer location
+ * @param time_ Current time
+ * @param user_data Pointer to queuelike
+ * @return TRUE in a dropzone, otherwise FALSE
+ */
+static gboolean ql_drag_motion(GtkWidget *w,
+ GdkDragContext *dc,
+ gint x,
+ gint y,
+ guint time_,
+ gpointer attribute((unused)) user_data) {
+ //struct queuelike *const ql = user_data;
+ GdkDragAction action = 0;
+
+ // GTK_DEST_DEFAULT_MOTION vets actions as follows:
+ // 1) if dc->suggested_action is in the gtk_drag_dest_set actions
+ // then dc->suggested_action is taken as the action.
+ // 2) otherwise if dc->actions intersects the gtk_drag_dest_set actions
+ // then the lowest-numbered member of the intersection is chosen.
+ // 3) otherwise no member is chosen and gdk_drag_status() is called
+ // with action=0 to refuse the drop.
+ if(dc->suggested_action) {
+ if(dc->suggested_action & (GDK_ACTION_MOVE|GDK_ACTION_COPY))
+ action = dc->suggested_action;
+ } else if(dc->actions & GDK_ACTION_MOVE)
+ action = GDK_ACTION_MOVE;
+ else if(dc->actions & GDK_ACTION_COPY)
+ action = GDK_ACTION_COPY;
+ /*fprintf(stderr, "suggested %#x actions %#x result %#x\n",
+ dc->suggested_action, dc->actions, action);*/
+ if(action) {
+ // If the action is acceptable then we see if this widget is acceptable
+ if(gtk_drag_dest_find_target(w, dc, NULL) == GDK_NONE)
+ action = 0;
+ }
+ // Report the status
+ gdk_drag_status(dc, action, time_);
+ if(action) {
+ // Highlight the drop area
+ GtkTreePath *path;
+ GtkTreeViewDropPosition pos;
+
+ if(gtk_tree_view_get_dest_row_at_pos(GTK_TREE_VIEW(w),
+ x, y,
+ &path,
+ &pos)) {
+ //fprintf(stderr, "gtk_tree_view_get_dest_row_at_pos() -> TRUE\n");
+ // Normalize drop position
+ switch(pos) {
+ case GTK_TREE_VIEW_DROP_INTO_OR_BEFORE:
+ pos = GTK_TREE_VIEW_DROP_BEFORE;
+ break;
+ case GTK_TREE_VIEW_DROP_INTO_OR_AFTER:
+ pos = GTK_TREE_VIEW_DROP_AFTER;
+ break;
+ default: break;
+ }
+ // Highlight drop target
+ gtk_tree_view_set_drag_dest_row(GTK_TREE_VIEW(w), path, pos);
+ } else {
+ //fprintf(stderr, "gtk_tree_view_get_dest_row_at_pos() -> FALSE\n");
+ gtk_tree_view_set_drag_dest_row(GTK_TREE_VIEW(w), NULL, 0);
+ }
+ }
+ return TRUE;
+}
+
+/** @brief Called when a drag moves leaves a candidate destination
+ * @param w Destination widget
+ * @param dc Drag context
+ * @param time_ Current time
+ * @param user_data Pointer to queuelike
+ */
+static void ql_drag_leave(GtkWidget *w,
+ GdkDragContext attribute((unused)) *dc,
+ guint attribute((unused)) time_,
+ gpointer attribute((unused)) user_data) {
+ //struct queuelike *const ql = user_data;
+
+ gtk_tree_view_set_drag_dest_row(GTK_TREE_VIEW(w), NULL, 0);