zoom in/out in timeline

common/utils/T/tracer/gui/gui.h

@@ -81,6 +81,8 @@ int new_color(gui *gui, char *color);
  *      - click      { int: button } (if enabled)
  * - timeline
  *      - resize     { int: width }
+ *      - scrollup   { void *: NULL }
+ *      - scrolldown { void *: NULL }
  */
 
 /* same type as in gui_defs.h */

common/utils/T/tracer/gui/timeline.c

@@ -54,6 +54,21 @@ static void allocate(gui *_gui, widget *_this,
   gui_notify(_gui, "resize", _this, &width);
 }
 
+static void button(gui *_g, widget *_this, int x, int y, int button, int up)
+{
+  struct gui *g = _g;
+  struct timeline_widget *this = _this;
+  LOGD("BUTTON timeline %p xy %d %d button %d up %d\n", _this, x, y, button, up);
+  /* scroll up */
+  if (button == 4 && up == 0) {
+    gui_notify(g, "scrollup", _this, NULL);
+  }
+  /* scroll down */
+  if (button == 5 && up == 0) {
+    gui_notify(g, "scrolldown", _this, NULL);
+  }
+}
+
 /*************************************************************************/
 /*                           creation function                           */
 /*************************************************************************/
@@ -87,6 +102,7 @@ widget *new_timeline(gui *_gui, int width, int number_of_sublines,
   w->common.paint = paint;
   w->common.hints = hints;
   w->common.allocate = allocate;
+  w->common.button = button;
 
   gunlock(g);