/** * @file lv_event.h * */ #ifndef LV_EVENT_H #define LV_EVENT_H #ifdef __cplusplus extern "C" { #endif /********************* * INCLUDES *********************/ #include /********************* * DEFINES *********************/ /********************** * TYPEDEFS **********************/ struct _lv_obj_t; struct _lv_event_dsc_t; /** * Type of event being sent to the object. */ typedef enum { LV_EVENT_ALL = 0, /** Input device events*/ LV_EVENT_PRESSED, /**< The object has been pressed*/ LV_EVENT_PRESSING, /**< The object is being pressed (called continuously while pressing)*/ LV_EVENT_PRESS_LOST, /**< The object is still being pressed but slid cursor/finger off of the object */ LV_EVENT_SHORT_CLICKED, /**< The object was pressed for a short period of time, then released it. Not called if scrolled.*/ LV_EVENT_LONG_PRESSED, /**< Object has been pressed for at least `long_press_time`. Not called if scrolled.*/ LV_EVENT_LONG_PRESSED_REPEAT, /**< Called after `long_press_time` in every `long_press_repeat_time` ms. Not called if scrolled.*/ LV_EVENT_CLICKED, /**< Called on release if not scrolled (regardless to long press)*/ LV_EVENT_RELEASED, /**< Called in every cases when the object has been released*/ LV_EVENT_SCROLL_BEGIN, /**< Scrolling begins*/ LV_EVENT_SCROLL_END, /**< Scrolling ends*/ LV_EVENT_SCROLL, /**< Scrolling*/ LV_EVENT_GESTURE, /**< A gesture is detected. Get the gesture with `lv_indev_get_gesture_dir(lv_indev_get_act());` */ LV_EVENT_KEY, /**< A key is sent to the object. Get the key with `lv_indev_get_key(lv_indev_get_act());`*/ LV_EVENT_FOCUSED, /**< The object is focused*/ LV_EVENT_DEFOCUSED, /**< The object is defocused*/ LV_EVENT_LEAVE, /**< The object is defocused but still selected*/ LV_EVENT_HIT_TEST, /**< Perform advanced hit-testing*/ /** Drawing events*/ LV_EVENT_COVER_CHECK, /**< Check if the object fully covers an area. The event parameter is `lv_cover_check_info_t *`.*/ LV_EVENT_REFR_EXT_DRAW_SIZE, /**< Get the required extra draw area around the object (e.g. for shadow). The event parameter is `lv_coord_t *` to store the size.*/ LV_EVENT_DRAW_MAIN_BEGIN, /**< Starting the main drawing phase*/ LV_EVENT_DRAW_MAIN, /**< Perform the main drawing*/ LV_EVENT_DRAW_MAIN_END, /**< Finishing the main drawing phase*/ LV_EVENT_DRAW_POST_BEGIN, /**< Starting the post draw phase (when all children are drawn)*/ LV_EVENT_DRAW_POST, /**< Perform the post draw phase (when all children are drawn)*/ LV_EVENT_DRAW_POST_END, /**< Finishing the post draw phase (when all children are drawn)*/ LV_EVENT_DRAW_PART_BEGIN, /**< Starting to draw a part. The event parameter is `lv_obj_draw_dsc_t *`. */ LV_EVENT_DRAW_PART_END, /**< Finishing to draw a part. The event parameter is `lv_obj_draw_dsc_t *`. */ /** Special events*/ LV_EVENT_VALUE_CHANGED, /**< The object's value has changed (i.e. slider moved)*/ LV_EVENT_INSERT, /**< A text is inserted to the object. The event data is `char *` being inserted.*/ LV_EVENT_REFRESH, /**< Notify the object to refresh something on it (for the user)*/ LV_EVENT_READY, /**< A process has finished*/ LV_EVENT_CANCEL, /**< A process has been cancelled */ /** Other events*/ LV_EVENT_DELETE, /**< Object is being deleted*/ LV_EVENT_CHILD_CHANGED, /**< Child was removed, added, or its size, position were changed */ LV_EVENT_CHILD_CREATED, /**< Child was created, always bubbles up to all parents*/ LV_EVENT_CHILD_DELETED, /**< Child was deleted, always bubbles up to all parents*/ LV_EVENT_SCREEN_UNLOAD_START, /**< A screen unload started, fired immediately when scr_load is called*/ LV_EVENT_SCREEN_LOAD_START, /**< A screen load started, fired when the screen change delay is expired*/ LV_EVENT_SCREEN_LOADED, /**< A screen was loaded*/ LV_EVENT_SCREEN_UNLOADED, /**< A screen was unloaded*/ LV_EVENT_SIZE_CHANGED, /**< Object coordinates/size have changed*/ LV_EVENT_STYLE_CHANGED, /**< Object's style has changed*/ LV_EVENT_LAYOUT_CHANGED, /**< The children position has changed due to a layout recalculation*/ LV_EVENT_GET_SELF_SIZE, /**< Get the internal size of a widget*/ _LV_EVENT_LAST, /** Number of default events*/ LV_EVENT_PREPROCESS = 0x80, /** This is a flag that can be set with an event so it's processed before the class default event processing */ } lv_event_code_t; typedef struct _lv_event_t { struct _lv_obj_t * target; struct _lv_obj_t * current_target; lv_event_code_t code; void * user_data; void * param; struct _lv_event_t * prev; uint8_t deleted : 1; uint8_t stop_processing : 1; uint8_t stop_bubbling : 1; } lv_event_t; /** * @brief Event callback. * Events are used to notify the user of some action being taken on the object. * For details, see ::lv_event_t. */ typedef void (*lv_event_cb_t)(lv_event_t * e); /** * Used as the event parameter of ::LV_EVENT_HIT_TEST to check if an `point` can click the object or not. * `res` should be set like this: * - If already set to `false` an other event wants that point non clickable. If you want to respect it leave it as `false` or set `true` to overwrite it. * - If already set `true` and `point` shouldn't be clickable set to `false` * - If already set to `true` you agree that `point` can click the object leave it as `true` */ typedef struct { const lv_point_t * point; /**< A point relative to screen to check if it can click the object or not*/ bool res; /**< true: `point` can click the object; false: it cannot*/ } lv_hit_test_info_t; /** * Used as the event parameter of ::LV_EVENT_COVER_CHECK to check if an area is covered by the object or not. * In the event use `const lv_area_t * area = lv_event_get_cover_area(e)` to get the area to check * and `lv_event_set_cover_res(e, res)` to set the result. */ typedef struct { lv_cover_res_t res; const lv_area_t * area; } lv_cover_check_info_t; /********************** * GLOBAL PROTOTYPES **********************/ /** * Send an event to the object * @param obj pointer to an object * @param event_code the type of the event from `lv_event_t` * @param param arbitrary data depending on the widget type and the event. (Usually `NULL`) * @return LV_RES_OK: `obj` was not deleted in the event; LV_RES_INV: `obj` was deleted in the event_code */ lv_res_t lv_event_send(struct _lv_obj_t * obj, lv_event_code_t event_code, void * param); /** * Used by the widgets internally to call the ancestor widget types's event handler * @param class_p pointer to the class of the widget (NOT the ancestor class) * @param e pointer to the event descriptor * @return LV_RES_OK: the target object was not deleted in the event; LV_RES_INV: it was deleted in the event_code */ lv_res_t lv_obj_event_base(const lv_obj_class_t * class_p, lv_event_t * e); /** * Get the object originally targeted by the event. It's the same even if the event is bubbled. * @param e pointer to the event descriptor * @return the target of the event_code */ struct _lv_obj_t * lv_event_get_target(lv_event_t * e); /** * Get the current target of the event. It's the object which event handler being called. * If the event is not bubbled it's the same as "normal" target. * @param e pointer to the event descriptor * @return pointer to the current target of the event_code */ struct _lv_obj_t * lv_event_get_current_target(lv_event_t * e); /** * Get the event code of an event * @param e pointer to the event descriptor * @return the event code. (E.g. `LV_EVENT_CLICKED`, `LV_EVENT_FOCUSED`, etc) */ lv_event_code_t lv_event_get_code(lv_event_t * e); /** * Get the parameter passed when the event was sent * @param e pointer to the event descriptor * @return pointer to the parameter */ void * lv_event_get_param(lv_event_t * e); /** * Get the user_data passed when the event was registered on the object * @param e pointer to the event descriptor * @return pointer to the user_data */ void * lv_event_get_user_data(lv_event_t * e); /** * Stop the event from bubbling. * This is only valid when called in the middle of an event processing chain. * @param e pointer to the event descriptor */ void lv_event_stop_bubbling(lv_event_t * e); /** * Stop processing this event. * This is only valid when called in the middle of an event processing chain. * @param e pointer to the event descriptor */ void lv_event_stop_processing(lv_event_t * e); /** * Register a new, custom event ID. * It can be used the same way as e.g. `LV_EVENT_CLICKED` to send custom events * @return the new event id * @example * uint32_t LV_EVENT_MINE = 0; * ... * e = lv_event_register_id(); * ... * lv_event_send(obj, LV_EVENT_MINE, &some_data); */ uint32_t lv_event_register_id(void); /** * Nested events can be called and one of them might belong to an object that is being deleted. * Mark this object's `event_temp_data` deleted to know that its `lv_event_send` should return `LV_RES_INV` * @param obj pointer to an object to mark as deleted */ void _lv_event_mark_deleted(struct _lv_obj_t * obj); /** * Add an event handler function for an object. * Used by the user to react on event which happens with the object. * An object can have multiple event handler. They will be called in the same order as they were added. * @param obj pointer to an object * @param filter and event code (e.g. `LV_EVENT_CLICKED`) on which the event should be called. `LV_EVENT_ALL` can be sued the receive all the events. * @param event_cb the new event function * @param user_data custom data data will be available in `event_cb` * @return a pointer the event descriptor. Can be used in ::lv_obj_remove_event_dsc */ struct _lv_event_dsc_t * lv_obj_add_event_cb(struct _lv_obj_t * obj, lv_event_cb_t event_cb, lv_event_code_t filter, void * user_data); /** * Remove an event handler function for an object. * @param obj pointer to an object * @param event_cb the event function to remove, or `NULL` to remove the firstly added event callback * @return true if any event handlers were removed */ bool lv_obj_remove_event_cb(struct _lv_obj_t * obj, lv_event_cb_t event_cb); /** * Remove an event handler function with a specific user_data from an object. * @param obj pointer to an object * @param event_cb the event function to remove, or `NULL` only `user_data` matters. * @param event_user_data the user_data specified in ::lv_obj_add_event_cb * @return true if any event handlers were removed */ bool lv_obj_remove_event_cb_with_user_data(struct _lv_obj_t * obj, lv_event_cb_t event_cb, const void * event_user_data); /** * DEPRECATED because doesn't work if multiple event handlers are added to an object. * Remove an event handler function for an object. * @param obj pointer to an object * @param event_dsc pointer to an event descriptor to remove (returned by ::lv_obj_add_event_cb) * @return true if any event handlers were removed */ bool lv_obj_remove_event_dsc(struct _lv_obj_t * obj, struct _lv_event_dsc_t * event_dsc); /** * The user data of an event object event callback. Always the first match with `event_cb` will be returned. * @param obj pointer to an object * @param event_cb the event function * @return the user_data */ void * lv_obj_get_event_user_data(struct _lv_obj_t * obj, lv_event_cb_t event_cb); /** * Get the input device passed as parameter to indev related events. * @param e pointer to an event * @return the indev that triggered the event or NULL if called on a not indev related event */ lv_indev_t * lv_event_get_indev(lv_event_t * e); /** * Get the part draw descriptor passed as parameter to `LV_EVENT_DRAW_PART_BEGIN/END`. * @param e pointer to an event * @return the part draw descriptor to hook the drawing or NULL if called on an unrelated event */ lv_obj_draw_part_dsc_t * lv_event_get_draw_part_dsc(lv_event_t * e); /** * Get the draw context which should be the first parameter of the draw functions. * Namely: `LV_EVENT_DRAW_MAIN/POST`, `LV_EVENT_DRAW_MAIN/POST_BEGIN`, `LV_EVENT_DRAW_MAIN/POST_END` * @param e pointer to an event * @return pointer to a draw context or NULL if called on an unrelated event */ lv_draw_ctx_t * lv_event_get_draw_ctx(lv_event_t * e); /** * Get the old area of the object before its size was changed. Can be used in `LV_EVENT_SIZE_CHANGED` * @param e pointer to an event * @return the old absolute area of the object or NULL if called on an unrelated event */ const lv_area_t * lv_event_get_old_size(lv_event_t * e); /** * Get the key passed as parameter to an event. Can be used in `LV_EVENT_KEY` * @param e pointer to an event * @return the triggering key or NULL if called on an unrelated event */ uint32_t lv_event_get_key(lv_event_t * e); /** * Get the animation descriptor of a scrolling. Can be used in `LV_EVENT_SCROLL_BEGIN` * @param e pointer to an event * @return the animation that will scroll the object. (can be modified as required) */ lv_anim_t * lv_event_get_scroll_anim(lv_event_t * e); /** * Set the new extra draw size. Can be used in `LV_EVENT_REFR_EXT_DRAW_SIZE` * @param e pointer to an event * @param size The new extra draw size */ void lv_event_set_ext_draw_size(lv_event_t * e, lv_coord_t size); /** * Get a pointer to an `lv_point_t` variable in which the self size should be saved (width in `point->x` and height `point->y`). * Can be used in `LV_EVENT_GET_SELF_SIZE` * @param e pointer to an event * @return pointer to `lv_point_t` or NULL if called on an unrelated event */ lv_point_t * lv_event_get_self_size_info(lv_event_t * e); /** * Get a pointer to an `lv_hit_test_info_t` variable in which the hit test result should be saved. Can be used in `LV_EVENT_HIT_TEST` * @param e pointer to an event * @return pointer to `lv_hit_test_info_t` or NULL if called on an unrelated event */ lv_hit_test_info_t * lv_event_get_hit_test_info(lv_event_t * e); /** * Get a pointer to an area which should be examined whether the object fully covers it or not. * Can be used in `LV_EVENT_HIT_TEST` * @param e pointer to an event * @return an area with absolute coordinates to check */ const lv_area_t * lv_event_get_cover_area(lv_event_t * e); /** * Set the result of cover checking. Can be used in `LV_EVENT_COVER_CHECK` * @param e pointer to an event * @param res an element of ::lv_cover_check_info_t */ void lv_event_set_cover_res(lv_event_t * e, lv_cover_res_t res); /********************** * MACROS **********************/ #ifdef __cplusplus } /*extern "C"*/ #endif #endif /*LV_EVENT_H*/