lv_indev_gesture.h

Typedefs

typedef struct lv_indev_gesture_recognizer lv_indev_gesture_recognizer_t

typedef struct lv_indev_touch_data lv_indev_touch_data_t

typedef struct lv_indev_gesture lv_indev_gesture_t

typedef struct lv_indev_gesture_configuration lv_indev_gesture_configuration_t

typedef void (*lv_recognizer_func_t)(lv_indev_gesture_recognizer_t*, lv_indev_touch_data_t*, uint16_t)

Enums

enum lv_indev_gesture_state_t

Values:

enumerator LV_INDEV_GESTURE_STATE_NONE

enumerator LV_INDEV_GESTURE_STATE_ONGOING

enumerator LV_INDEV_GESTURE_STATE_RECOGNIZED

enumerator LV_INDEV_GESTURE_STATE_ENDED

enumerator LV_INDEV_GESTURE_STATE_CANCELED

Functions

void lv_indev_gesture_detect_pinch(lv_indev_gesture_recognizer_t *recognizer, lv_indev_touch_data_t *touches, uint16_t touch_cnt)

Pinch gesture recognizer function Will update the recognizer data

Parameters:

recognizer – pointer to a gesture recognizer
touches – pointer to the first element of the collected touch events
touch_cnt – length of passed touch event array.

void lv_indev_gesture_detect_rotation(lv_indev_gesture_recognizer_t *recognizer, lv_indev_touch_data_t *touches, uint16_t touch_cnt)

Rotation gesture recognizer function Will update the recognizer data

Parameters:

recognizer – pointer to a gesture recognizer
touches – pointer to the first element of the collected touch events
touch_cnt – length of passed touch event array.

void lv_indev_gesture_detect_two_fingers_swipe(lv_indev_gesture_recognizer_t *recognizer, lv_indev_touch_data_t *touches, uint16_t touch_cnt)

Two finger swipe gesture recognizer function Will update the recognizer data

Parameters:

recognizer – pointer to a gesture recognizer
touches – pointer to the first element of the collected touch events
touch_cnt – length of passed touch event array.

void lv_indev_set_pinch_up_threshold(lv_indev_t *indev, float threshold)

Set the threshold for the pinch gesture scale up, when the scale factor of gesture reaches the threshold events get sent

Parameters:

indev – pointer to the indev device containing the pinch recognizer
threshold – threshold for a pinch up gesture to be recognized

void lv_indev_set_pinch_down_threshold(lv_indev_t *indev, float threshold)

Set the threshold for the pinch gesture scale down, when the scale factor of gesture reaches the threshold events get sent

Parameters:

indev – pointer to the indev device containing the pinch recognizer
threshold – threshold for a pinch down gesture to be recognized

void lv_indev_set_rotation_rad_threshold(lv_indev_t *indev, float threshold)

Set the rotation threshold in radian for the rotation gesture

Parameters:

indev – pointer to the indev device containing the rotation recognizer
threshold – threshold in radian for a rotation gesture to be recognized

float lv_event_get_pinch_scale(lv_event_t *gesture_event)

Obtains the current scale of a pinch gesture

Parameters:: gesture_event – pointer to a gesture event
Returns:: the scale of the current gesture

float lv_event_get_rotation(lv_event_t *gesture_event)

Obtains the current angle in radian of a rotation gesture

Parameters:: gesture_event – pointer to a gesture event
Returns:: the rotation angle in radian of the current gesture

float lv_event_get_two_fingers_swipe_distance(lv_event_t *gesture_event)

Obtains the current distance in pixels of a two fingers swipe gesture, from the starting center

Parameters:: gesture_event – pointer to a gesture event
Returns:: the distance from the center, in pixels, of the current gesture

lv_dir_t lv_event_get_two_fingers_swipe_dir(lv_event_t *gesture_event)

Obtains the current direction from the center of a two finger swipe

Parameters:: gesture_event – pointer to a gesture event
Returns:: the rotation angle in radian of the current gesture

void lv_indev_set_gesture_data(lv_indev_data_t *data, lv_indev_gesture_recognizer_t *recognizer, lv_indev_gesture_type_t type)

Sets the state of the recognizer to a indev data structure, it is usually called from the indev read callback

Parameters:

data – the indev data
recognizer – pointer to a gesture recognizer

void lv_indev_get_gesture_center_point(lv_indev_gesture_recognizer_t *recognizer, lv_point_t *point)

Obtains the center point of a gesture

Parameters:

gesture_event – pointer to a gesture recognizer event
point – pointer to a point

lv_indev_gesture_state_t lv_event_get_gesture_state(lv_event_t *gesture_event, lv_indev_gesture_type_t type)

Obtains the current state of the gesture recognizer attached to an event

Parameters:: gesture_event – pointer to a gesture recognizer event
Returns:: current state of the gesture recognizer

lv_indev_gesture_type_t lv_event_get_gesture_type(lv_event_t *gesture_event)

Obtains the current event type of the gesture recognizer attached to an event

Parameters:: gesture_event – pointer to a gesture recognizer event
Returns:: current event type of the gesture recognizer

void lv_indev_get_gesture_primary_point(lv_indev_gesture_recognizer_t *recognizer, lv_point_t *point)

Obtains the coordinates of the current primary point

Parameters:

recognizer – pointer to a gesture recognizer
point – pointer to a point

bool lv_indev_recognizer_is_active(lv_indev_gesture_recognizer_t *recognizer)

Allows to determine if there is an are ongoing gesture

Parameters:: recognizer – pointer to a gesture recognizer
Returns:: false if there are no contact points, or the gesture has ended - true otherwise

void lv_indev_gesture_recognizers_update(lv_indev_t *indev, lv_indev_touch_data_t *touches, uint16_t touch_cnt)

Update the recognizers. It execute the recognizers functions and checks for LV_GESTURE_STATE_RECOGNIZED or LV_GESTURE_STATE_ENDED gestures. To be called in the indev read_cb.

Parameters:

indev – pointer to the indev containing from which the reconizer need an update
touches – indev touch data array, containing the last touch data from indev since the last recognizers update
touch_cnt – number of indev touch data in touches

void lv_indev_gesture_recognizers_set_data(lv_indev_t *indev, lv_indev_data_t *data): Set the lv_indev_data_t struct from the recognizer data. To be called in the indev read_cb.