marcp/domotic
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
domotic/components/lvgl__lvgl/examples/others/gestures/lv_example_gestures.c
Marc PASTEUR d132f39ff8 move lvgl
2025-12-19 18:08:19 +01:00

284 lines
8.3 KiB
C
Raw Blame History

/*******************************************************************
*
* @file lv_example_gestures.c
*
* This is a simple example program that demonstrates how to use
* the gesture recognition API, please refer to lv_indev_gesture.h or the documentation
* for more details
*
* The application starts with a single rectangle. The user can then
* - Pinch the rectangle to scale it
* - Rotate the rectangle to rotate it
* - Two fingers swipe the rectangle to see the direction and the distance of the swipe
*
* Copyright (c) 2024 EDGEMTech Ltd
*
* Author: EDGEMTech Ltd, Erik Tagirov (erik.tagirov@edgemtech.ch)
*
******************************************************************/
/*********************
* INCLUDES
*********************/
#include "../../lv_examples.h"
#if LV_USE_GESTURE_RECOGNITION && LV_BUILD_EXAMPLES
/*********************
* DEFINES
*********************/
#define RECT_INIT_WIDTH 300
#define RECT_INIT_HEIGHT 300
#define RECT_COLOR 0xC1BCFF
#ifndef M_PI
#define M_PI 3.1415926f
#endif
/**********************
* TYPEDEFS
**********************/
/**********************
* STATIC PROTOTYPES
**********************/
static void label_scale(lv_event_t * gesture_event);
static void label_rotate(lv_event_t * gesture_event);
static void label_swipe(lv_event_t * gesture_event);
/**********************
* STATIC VARIABLES
**********************/
static lv_obj_t * label;
static lv_style_t label_style;
static uint32_t label_width;
static uint32_t label_height;
static uint32_t label_x;
static uint32_t label_y;
/**********************
* MACROS
**********************/
/**********************
* GLOBAL FUNCTIONS
**********************/
/**
* Entry point it creates the screen, and the label
* Set event callbacks on the label
*/
void lv_example_gestures(void)
{
lv_obj_t * root_view;
label_width = RECT_INIT_WIDTH;
label_height = RECT_INIT_HEIGHT;
label_x = LV_HOR_RES / 2 - (label_width / 2);
label_y = LV_VER_RES / 2 - (label_height / 2);
root_view = lv_screen_active();
lv_obj_set_style_bg_color(root_view, lv_color_hex(0xffffff), LV_PART_MAIN);
label = lv_label_create(root_view);
lv_obj_remove_flag(root_view, LV_OBJ_FLAG_SCROLLABLE);
lv_label_set_text(label, "Zoom, rotate or move");
lv_obj_add_flag(label, LV_OBJ_FLAG_CLICKABLE);
lv_style_init(&label_style);
lv_style_set_bg_color(&label_style, lv_color_hex(RECT_COLOR));
lv_style_set_bg_opa(&label_style, LV_OPA_COVER);
lv_style_set_width(&label_style, (int)label_width);
lv_style_set_height(&label_style, (int)label_height);
lv_style_set_x(&label_style, (int)label_x);
lv_style_set_y(&label_style, (int)label_y);
lv_obj_add_style(label, &label_style, LV_STATE_DEFAULT);
lv_obj_add_event_cb(label, label_rotate, LV_EVENT_GESTURE, label);
lv_obj_add_event_cb(label, label_scale, LV_EVENT_GESTURE, label);
lv_obj_add_event_cb(label, label_swipe, LV_EVENT_GESTURE, label);
}
/**********************
* STATIC FUNCTIONS
**********************/
/**
* Called when a LV_EVENT_GESTURE event occurs - update the label if the gesture is a swipe
* @param gesture_event pointer to a LV_EVENT_GESTURE event
*/
static void label_swipe(lv_event_t * gesture_event)
{
lv_dir_t dir;
lv_indev_gesture_state_t state;
const char * text;
if(lv_event_get_gesture_type(gesture_event) != LV_INDEV_GESTURE_TWO_FINGERS_SWIPE) {
return;
}
state = lv_event_get_gesture_state(gesture_event, LV_INDEV_GESTURE_TWO_FINGERS_SWIPE);
dir = lv_event_get_two_fingers_swipe_dir(gesture_event);
if(state == LV_INDEV_GESTURE_STATE_ENDED) {
text = "NONE";
lv_label_set_text(label, text);
}
else if(state == LV_INDEV_GESTURE_STATE_RECOGNIZED) {
switch(dir) {
case LV_DIR_LEFT:
text = "LEFT";
break;
case LV_DIR_RIGHT:
text = "RIGHT";
break;
case LV_DIR_TOP:
text = "TOP";
break;
case LV_DIR_BOTTOM:
text = "BOTTOM";
break;
default:
text = "???";
break;
}
lv_label_set_text_fmt(label, "%s - %f", text, lv_event_get_two_fingers_swipe_distance(gesture_event));
}
}
/**
* Called when a LV_EVENT_GESTURE event occurs - scales the label if the gesture is a pinch
* @param gesture_event pointer to a LV_EVENT_GESTURE event
*/
static void label_scale(lv_event_t * gesture_event)
{
static int initial_w = -1;
static int initial_h = -1;
lv_indev_gesture_state_t state;
static lv_point_t center_pnt;
static float base_scale = 1.0;
float scale;
float label_width_float;
float label_height_float;
/* Ensure the gesture is a pinch */
if(lv_event_get_gesture_type(gesture_event) != LV_INDEV_GESTURE_PINCH) {
return;
}
state = lv_event_get_gesture_state(gesture_event, LV_INDEV_GESTURE_PINCH);
scale = base_scale * lv_event_get_pinch_scale(gesture_event);
/* Reset state when the gesture ended */
if(state == LV_INDEV_GESTURE_STATE_ENDED) {
/* Pinch gesture has ended - reset the width/height for the next pinch gesture*/
initial_w = -1;
initial_h = -1;
base_scale = scale;
return;
}
/* The first time the gesture is recognized, save its center */
if(state == LV_INDEV_GESTURE_STATE_RECOGNIZED) {
if((initial_h == -1 || initial_w == -1)) {
/* Pinch gesture has been recognized - this is the first event in a series of recognized events */
/* The scaling is applied relative to the original width/height of the rectangle */
initial_w = label_width;
initial_h = label_height;
center_pnt.x = lv_obj_get_x(label) + label_width / 2;
center_pnt.y = lv_obj_get_y(label) + label_height / 2;
}
/* The gesture is recognized, we can now use the scale */
/* Avoids a situation where the rectangle becomes too small or too big,
* adding limits */
if(scale < 0.4f) {
scale = 0.4f;
}
else if(scale > 2.0f) {
scale = 2.0f;
}
label_x = center_pnt.x - label_width / 2;
label_y = center_pnt.y - label_height / 2;
label_width_float = (float)RECT_INIT_WIDTH * scale;
label_height_float = (float)RECT_INIT_HEIGHT * scale;
/* Update position and size */
lv_style_set_width(&label_style, (int)label_width_float);
lv_style_set_height(&label_style, (int)label_height_float);
lv_style_set_x(&label_style, (int)label_x);
lv_style_set_y(&label_style, (int)label_y);
lv_obj_add_style(label, &label_style, LV_STATE_DEFAULT);
label_width = (int)label_width_float;
label_height = (int)label_height_float;
}
}
/**
* Called when a LV_EVENT_GESTURE event occurs - rotate the label if the gesture is a rotation
* @param gesture_event pointer to a LV_EVENT_GESTURE event
*/
static void label_rotate(lv_event_t * gesture_event)
{
float angle_degrees = 0.f;
static float start_angle = 0.f;
lv_indev_gesture_state_t state;
if(lv_event_get_gesture_type(gesture_event) != LV_INDEV_GESTURE_ROTATE) {
return;
}
state = lv_event_get_gesture_state(gesture_event, LV_INDEV_GESTURE_ROTATE);
/* Calculate new angle. The x10 is due to lv_obj_set_style_transform_rotation using x10 angle in parameter */
angle_degrees = start_angle + 10.0f * (lv_event_get_rotation(gesture_event) * 180.0f / M_PI);
/* Once the gesture ends, save the current angle to the start_angle */
if(state == LV_INDEV_GESTURE_STATE_ENDED) {
start_angle = angle_degrees;
}
/* If the gesture is recognized, rotate the label */
if(state == LV_INDEV_GESTURE_STATE_RECOGNIZED) {
/* Need to set the pivot to the center of the widget to not rotate
around the top-left corner */
lv_obj_set_style_transform_pivot_x(label, lv_obj_get_width(label) / 2, 0);
lv_obj_set_style_transform_pivot_y(label, lv_obj_get_height(label) / 2, 0);
lv_obj_set_style_transform_rotation(label, (int) angle_degrees, 0);
}
return;
}
#endif /* LV_USE_GESTURE_RECOGNITION && LV_USE_FLOAT */
Reference in New Issue View Git Blame Copy Permalink