text: /**
   * @file lv_demo_keypad_encoder.c
   *
   */
  
  /*********************
   *      INCLUDES
   *********************/
  #include "../../lv_examples.h"
  #include "lv_demo_keypad_encoder.h"
  #if LV_EX_KEYBOARD
  #include "indev/keyboard.h"
  #endif
  #if LV_EX_MOUSEWHEEL
  #include "indev/mousewheel.h"
  #endif
  
  #if LV_USE_DEMO_KEYPAD_AND_ENCODER
  
  /*********************
   *      DEFINES
   *********************/
  
  /**********************
   *      TYPEDEFS
   **********************/
  
  /**********************
   *  STATIC PROTOTYPES
   **********************/
  static void selectors_create(lv_obj_t * parent);
  static void text_input_create(lv_obj_t * parent);
  static void msgbox_create(void);
  
  static void focus_cb(lv_group_t * g);
  static void msgbox_event_cb(lv_obj_t * msgbox, lv_event_t e);
  static void tv_event_cb(lv_obj_t * ta, lv_event_t e);
  static void ta_event_cb(lv_obj_t * ta, lv_event_t e);
  static void kb_event_cb(lv_obj_t * kb, lv_event_t e);
  
  /**********************
   *  STATIC VARIABLES
   **********************/
  static lv_group_t*  g;
  static lv_obj_t * tv;
  static lv_obj_t * t1;
  static lv_obj_t * t2;
  static lv_obj_t * t3;
  
  struct {
      lv_obj_t * btn;
      lv_obj_t * cb;
      lv_obj_t * slider;
      lv_obj_t * sw;
      lv_obj_t * spinbox;
      lv_obj_t * dropdown;
      lv_obj_t * roller;
      lv_obj_t * list;
  }selector_objs;
  
  struct {
      lv_obj_t * ta1;
      lv_obj_t * ta2;
      lv_obj_t * kb;
  }textinput_objs;
  
  /**********************
   *      MACROS
   **********************/
  
  /**********************
   *   GLOBAL FUNCTIONS
   **********************/
  
  LV_EVENT_CB_DECLARE(dd_enc)
  {
      if(e == LV_EVENT_VALUE_CHANGED) {
          printf("chg\n");
      }
  }
  
  void lv_demo_keypad_encoder(void)
  {
      g = lv_group_create();
      lv_group_set_focus_cb(g, focus_cb);
  
  #if LV_EX_KEYBOARD
      lv_indev_drv_t kb_drv;
      lv_indev_drv_init(&kb_drv);
      kb_drv.type = LV_INDEV_TYPE_KEYPAD;
      kb_drv.read_cb = keyboard_read;
      lv_indev_t * kb_indev = lv_indev_drv_register(&kb_drv);
      lv_indev_set_group(kb_indev, g);
  #endif
  
  #if LV_EX_MOUSEWHEEL
      lv_indev_drv_t enc_drv;
      lv_indev_drv_init(&enc_drv);
      enc_drv.type = LV_INDEV_TYPE_ENCODER;
      enc_drv.read_cb = mousewheel_read;
      lv_indev_t * enc_indev = lv_indev_drv_register(&enc_drv);
      lv_indev_set_group(enc_indev, g);
  #endif
  
      tv = lv_tabview_create(lv_scr_act(), NULL);
      lv_obj_set_event_cb(tv, tv_event_cb);
  
      t1 = lv_tabview_add_tab(tv, "Selectors");
      t2 = lv_tabview_add_tab(tv, "Text input");
  
      lv_group_add_obj(g, tv);
  
      selectors_create(t1);
      text_input_create(t2);
  
      msgbox_create();
  }
  
  /**********************
   *   STATIC FUNCTIONS
   **********************/
  
  static void selectors_create(lv_obj_t * parent)
  {
      lv_page_set_scrl_layout(parent, LV_LAYOUT_COLUMN_MID);
  
     selector_objs.btn = lv_btn_create(parent, NULL);
  
     lv_obj_t * label = lv_label_create(selector_objs.btn, NULL);
     lv_label_set_text(label, "Button");
  
     selector_objs.cb = lv_checkbox_create(parent, NULL);
  
     selector_objs.slider = lv_slider_create(parent, NULL);
     lv_slider_set_range(selector_objs.slider, 0, 10);
  
     selector_objs.sw = lv_switch_create(parent, NULL);
  
     selector_objs.spinbox = lv_spinbox_create(parent, NULL);
  
     selector_objs.dropdown = lv_dropdown_create(parent, NULL);
     lv_obj_set_event_cb(selector_objs.dropdown, dd_enc);
  
     selector_objs.roller = lv_roller_create(parent, NULL);
  
     selector_objs.list = lv_list_create(parent, NULL);
     if(lv_obj_get_height(selector_objs.list) > lv_page_get_height_fit(parent)) {
         lv_obj_set_height(selector_objs.list, lv_page_get_height_fit(parent));
     }
     lv_list_add_btn(selector_objs.list, LV_SYMBOL_OK, "Apply");
     lv_list_add_btn(selector_objs.list, LV_SYMBOL_CLOSE, "Close");
     lv_list_add_btn(selector_objs.list, LV_SYMBOL_EYE_OPEN, "Show");
     lv_list_add_btn(selector_objs.list, LV_SYMBOL_EYE_CLOSE, "Hide");
     lv_list_add_btn(selector_objs.list, LV_SYMBOL_TRASH, "Delete");
     lv_list_add_btn(selector_objs.list, LV_SYMBOL_COPY, "Copy");
     lv_list_add_btn(selector_objs.list, LV_SYMBOL_PASTE, "Paste");
  }
  
  static void text_input_create(lv_obj_t * parent)
  {
      textinput_objs.ta1 = lv_textarea_create(parent, NULL);
      lv_obj_set_event_cb(textinput_objs.ta1, ta_event_cb);
      lv_obj_align(textinput_objs.ta1, NULL, LV_ALIGN_IN_TOP_MID, 0, LV_DPI / 20);
      lv_textarea_set_one_line(textinput_objs.ta1, true);
      lv_textarea_set_cursor_hidden(textinput_objs.ta1, true);
      lv_textarea_set_placeholder_text(textinput_objs.ta1, "Type something");
      lv_textarea_set_text(textinput_objs.ta1, "");
  
      textinput_objs.ta2 = lv_textarea_create(parent, textinput_objs.ta1);
      lv_obj_align(textinput_objs.ta2, textinput_objs.ta1, LV_ALIGN_OUT_BOTTOM_MID, 0, LV_DPI / 20);
  
      textinput_objs.kb = NULL;
  }
  
  static void msgbox_create(void)
  {
      lv_obj_t * mbox = lv_msgbox_create(lv_layer_top(), NULL);
      lv_msgbox_set_text(mbox, "Welcome to the keyboard and encoder demo");
      lv_obj_set_event_cb(mbox, msgbox_event_cb);
      lv_group_add_obj(g, mbox);
      lv_group_focus_obj(mbox);
  #if LV_EX_MOUSEWHEEL
      lv_group_set_editing(g, true);
  #endif
      lv_group_focus_freeze(g, true);
  
      static const char * btns[] = {"Ok", "Cancel", ""};
      lv_msgbox_add_btns(mbox, btns);
      lv_obj_align(mbox, NULL, LV_ALIGN_CENTER, 0, 0);
  
      lv_obj_set_style_local_bg_opa(lv_layer_top(), LV_OBJ_PART_MAIN, LV_STATE_DEFAULT, LV_OPA_70);
      lv_obj_set_style_local_bg_color(lv_layer_top(), LV_OBJ_PART_MAIN, LV_STATE_DEFAULT, LV_COLOR_GRAY);
      lv_obj_set_click(lv_layer_top(), true);
  }
  
  
  static void msgbox_event_cb(lv_obj_t * msgbox, lv_event_t e)
  {
      if(e == LV_EVENT_CLICKED) {
          uint16_t b = lv_msgbox_get_active_btn(msgbox);
          if(b == 0 || b == 1) {
              lv_obj_del(msgbox);
              lv_obj_reset_style_list(lv_layer_top(), LV_OBJ_PART_MAIN);
              lv_obj_set_click(lv_layer_top(), false);
              lv_event_send(tv, LV_EVENT_REFRESH, NULL);
          }
      }
  }
  
  static void focus_cb(lv_group_t * group)
  {
      lv_obj_t * obj = lv_group_get_focused(group);
      if(obj != tv) {
          uint16_t tab = lv_tabview_get_tab_act(tv);
          switch(tab) {
          case 0:
              lv_page_focus(t1, obj, LV_ANIM_ON);
              break;
          case 1:
              lv_page_focus(t2, obj, LV_ANIM_ON);
              break;
          case 2:
              lv_page_focus(t3, obj, LV_ANIM_ON);
              break;
          }
      }
  }
  
  static void tv_event_cb(lv_obj_t * ta, lv_event_t e)
  {
      if(e == LV_EVENT_VALUE_CHANGED || e == LV_EVENT_REFRESH) {
          lv_group_remove_all_objs(g);
  
          uint16_t tab = lv_tabview_get_tab_act(tv);
          size_t size = 0;
          lv_obj_t ** objs = NULL;
          if(tab == 0) {
              size = sizeof(selector_objs);
              objs = (lv_obj_t**) &selector_objs;
          }
          else if(tab == 1) {
              size = sizeof(textinput_objs);
              objs = (lv_obj_t**) &textinput_objs;
          }
  
          lv_group_add_obj(g, tv);
  
          uint32_t i;
          for(i = 0; i < size / sizeof(lv_obj_t *); i++) {
              if(objs[i] == NULL) continue;
              lv_group_add_obj(g, objs[i]);
          }
  
      }
  
  }
  
  static void ta_event_cb(lv_obj_t * ta, lv_event_t e)
  {
      /*Create a virtual keyboard for the encoders*/
      lv_indev_t * indev = lv_indev_get_act();
      if(indev == NULL) return;
      lv_indev_type_t indev_type = lv_indev_get_type(indev);
  
      if(e == LV_EVENT_FOCUSED) {
          lv_textarea_set_cursor_hidden(ta, false);
          if(lv_group_get_editing(g)) {
              if(textinput_objs.kb == NULL) {
                  textinput_objs.kb = lv_keyboard_create(lv_scr_act(), NULL);
                  lv_group_add_obj(g, textinput_objs.kb);
                  lv_obj_set_event_cb(textinput_objs.kb, kb_event_cb);
                  lv_obj_set_height(tv, LV_VER_RES - lv_obj_get_height(textinput_objs.kb));
              }
  
              lv_keyboard_set_textarea(textinput_objs.kb, ta);
              lv_group_focus_obj(textinput_objs.kb);
              lv_group_set_editing(g, true);
              lv_page_focus(t2, lv_textarea_get_label(ta), LV_ANIM_ON);
          }
      }
      else if(e == LV_EVENT_DEFOCUSED) {
          if(indev_type == LV_INDEV_TYPE_ENCODER) {
              if(textinput_objs.kb == NULL) {
                  lv_textarea_set_cursor_hidden(ta, true);
              }
          } else {
              lv_textarea_set_cursor_hidden(ta, true);
          }
      }
  }
  
  static void kb_event_cb(lv_obj_t * kb, lv_event_t e)
  {
      lv_keyboard_def_event_cb(kb, e);
  
      if(e == LV_EVENT_APPLY || e == LV_EVENT_CANCEL) {
          lv_group_focus_obj(lv_keyboard_get_textarea(kb));
          lv_obj_del(kb);
          textinput_objs.kb = NULL;
          lv_obj_set_height(tv, LV_VER_RES);
      }
  }
  
  #endif
  