capitalize folder names and file names Same like class file names

src/Display/Display.h

@@ -0,0 +1,57 @@
+#ifndef _AIR_GRADIENT_OLED_H_
+#define _AIR_GRADIENT_OLED_H_
+
+#include "../main/BoardDef.h"
+#include <Arduino.h>
+#include <Wire.h>
+
+/**
+ * @brief The class define how to handle the OLED display on Airgradient has
+ * attached or support OLED display like: ONE-V9, Basic-V4
+ */
+class Display {
+public:
+  const uint16_t COLOR_WHILTE = 1;
+  const uint16_t COLOR_BLACK = 0;
+#if defined(ESP8266)
+  void begin(TwoWire &wire, Stream &debugStream);
+#else
+#endif
+  Display(BoardType type);
+  void begin(TwoWire &wire);
+  void end(void);
+
+  void clear(void);
+  void invertDisplay(uint8_t i);
+  void show();
+
+  void setContrast(uint8_t value);
+  void drawPixel(int16_t x, int16_t y, uint16_t color);
+  void setTextSize(int size);
+  void setCursor(int16_t x, int16_t y);
+  void setTextColor(uint16_t color);
+  void setTextColor(uint16_t foreGroundColor, uint16_t backGroundColor);
+  void setText(String text);
+  void setText(const char text[]);
+  void drawBitmap(int16_t x, int16_t y, const uint8_t bitmap[], int16_t w,
+                  int16_t h, uint16_t color);
+  void drawLine(int x0, int y0, int x1, int y1, uint16_t color);
+  void drawCircle(int x, int y, int r, uint16_t color);
+  void drawRect(int x0, int y0, int x1, int y1, uint16_t color);
+  void setRotation(uint8_t r);
+
+private:
+  BoardType _boardType;
+  const BoardDef *_bsp = nullptr;
+  void *oled;
+  bool _isBegin = false;
+#if defined(ESP8266)
+  const char *TAG = "oled";
+  Stream *_debugStream = nullptr;
+#else
+
+#endif
+  bool isBegin(void);
+};
+
+#endif /** _AIR_GRADIENT_OLED_H_ */