feat(gif): add API to pause/resume gif timer (#4854)

Signed-off-by: wangxuedong <wangxuedong@xiaomi.com>

src/libs/gif/lv_gif.c

@@ -106,6 +106,18 @@ void lv_gif_restart(lv_obj_t * obj)
     lv_timer_reset(gifobj->timer);
 }
 
+void lv_gif_pause(lv_obj_t * obj)
+{
+    lv_gif_t * gifobj = (lv_gif_t *) obj;
+    lv_timer_pause(gifobj->timer);
+}
+
+void lv_gif_resume(lv_obj_t * obj)
+{
+    lv_gif_t * gifobj = (lv_gif_t *) obj;
+    lv_timer_resume(gifobj->timer);
+}
+
 /**********************
  *   STATIC FUNCTIONS
  **********************/

src/libs/gif/lv_gif.h

@@ -41,9 +41,38 @@ extern const lv_obj_class_t lv_gif_class;
  * GLOBAL PROTOTYPES
  **********************/
 
+/**
+ * Create a gif object
+ * @param parent    pointer to an object, it will be the parent of the new gif.
+ * @return          pointer to the gif obj
+ */
 lv_obj_t * lv_gif_create(lv_obj_t * parent);
+
+/**
+ * Set the gif data to display on the object
+ * @param obj       pointer to a gif object
+ * @param src       1) pointer to an ::lv_image_dsc_t descriptor (which contains gif raw data) or
+ *                  2) path to a gif file (e.g. "S:/dir/anim.gif")
+ */
 void lv_gif_set_src(lv_obj_t * obj, const void * src);
-void lv_gif_restart(lv_obj_t * gif);
+
+/**
+ * Restart a gif animation.
+ * @param obj pointer to a gif obj
+ */
+void lv_gif_restart(lv_obj_t * obj);
+
+/**
+ * Pause a gif animation.
+ * @param obj pointer to a gif obj
+ */
+void lv_gif_pause(lv_obj_t * obj);
+
+/**
+ * Resume a gif animation.
+ * @param obj pointer to a gif obj
+ */
+void lv_gif_resume(lv_obj_t * obj);
 
 /**********************
  *      MACROS