1、refactor battery indicator

widgets/battery_indicator.h

@@ -0,0 +1,14 @@
+#pragma once
+#include "lvgl.h"
+
+typedef struct _lv_battery_indicator_t lv_battery_indicator_t;
+
+lv_obj_t* lv_battery_indicator_create(lv_obj_t* parent);
+
+void lv_battery_indicator_set_percentage(lv_obj_t* obj, uint8_t value);
+
+uint8_t lv_battery_indicator_get_percentage(lv_obj_t* obj);
+
+void lv_battery_indicator_set_text_color_hex(lv_obj_t* obj, uint32_t c);
+
+void lv_battery_indicator_set_text_bg_color_hex(lv_obj_t* obj, uint32_t c);