add touch management to LVGL Demo

Author: leonardocavagnis

libraries/H7_Video/examples/LVGLDemo/LVGLDemo.ino

@@ -4,14 +4,36 @@
 
 H7_Video Display(480,800);
 
-//@TODO: Complete demo with 4 main features + touch management
+//@TODO: Complete demo with 4 main features
+
+void my_touchpad_read(lv_indev_drv_t * indev, lv_indev_data_t * data) {
+  data->state = (touchpad_pressed) ? LV_INDEV_STATE_PR : LV_INDEV_STATE_REL;
+  if(data->state == LV_INDEV_STATE_PR) {
+    data->point.x = giga_get_touch_x();
+    data->point.y = giga_get_touch_y();
+    touchpad_pressed = false;
+
+    Serial.print("Touch detected: ");
+    Serial.print(data->point.x);
+    Serial.print(",");
+    Serial.println(data->point.y);
+  }
+  
+  return;
+}
 
 void setup() {
   Serial.begin(115200);
   giga_touch_setup();
 
   Display.begin();
 
+  static lv_indev_drv_t indev_drv;                            /* Descriptor of a input device driver */
+  lv_indev_drv_init(&indev_drv);                              /* Basic initialization */
+  indev_drv.type = LV_INDEV_TYPE_POINTER;                     /* Touch pad is a pointer-like device */
+  indev_drv.read_cb = my_touchpad_read;                       /* Set your driver function */
+  lv_indev_t * my_indev = lv_indev_drv_register(&indev_drv);  /* Register the driver in LVGL and save the created input device object */
+
   /* Change the active screen's background color */
   lv_obj_set_style_bg_color(lv_scr_act(), lv_color_hex(0x03989e), LV_PART_MAIN);
 
@@ -24,7 +46,7 @@ void setup() {
 
 void loop() { 
   /* Touch handler */
-  giga_touch_loop();
+  giga_touch_handler();
 
   /* Feed LVGL engine */
   lv_timer_handler();

libraries/H7_Video/examples/LVGLDemo/giga_touch.cpp

@@ -24,13 +24,13 @@ bool touchpad_pressed;
 
 void handleTouch(int8_t contacts, GTPoint *points) {
   touchpad_pressed = true;
-  printf("Contacts: %d\n", contacts);
+  //printf("Contacts: %d\n", contacts);
   for (uint8_t i = 0; i < contacts; i++) {
     if (i == 0) {
       touchpad_x = points[i].x;
       touchpad_y = points[i].y;
     }
-    printf("C%d: #%d %d,%d s:%d\n", i, points[i].trackId, points[i].x, points[i].y, points[i].area);
+    //printf("C%d: #%d %d,%d s:%d\n", i, points[i].trackId, points[i].x, points[i].y, points[i].area);
     yield();
   }
 }
@@ -57,8 +57,6 @@ void touchStart() {
 }
 
 void giga_touch_setup() {
-  Serial.println("\nGoodix GT911x touch driver");
-
   Wire.setClock(400000);
   Wire.begin();
   delay(300);
@@ -67,7 +65,15 @@ void giga_touch_setup() {
   touchStart();
 }
 
-void giga_touch_loop() {
+void giga_touch_handler() {
   touch.loop();
   delay(1);
 }
+
+uint16_t giga_get_touch_x() {
+  return touchpad_x;
+}
+
+uint16_t giga_get_touch_y() {
+  return touchpad_y;
+}

libraries/H7_Video/examples/LVGLDemo/giga_touch.h

@@ -1,6 +1,7 @@
-extern uint16_t touchpad_x;
-extern uint16_t touchpad_y;
-extern bool touchpad_pressed;
-
 void giga_touch_setup();
-void giga_touch_loop();
+void giga_touch_handler();
+
+uint16_t giga_get_touch_x();
+uint16_t giga_get_touch_y();
+
+extern bool touchpad_pressed;