触发按钮控制 LED 的亮灭

• Traditional way

int main(void) { 
          while(1)  { 
           if (read_gpio_pin_key())   { 
            write_gpio_pin_led();   }  } } 

• OOP way

typedef struct LEDDevice { 
          int group;  int pin;  void (*Init)(struct LEDDevice *pDev);  void (*Control)(struct LEDDevice *pDev, int iStatus); } LEDDevice, *pLEDDevice;  void autumn_LED_Init(struct LEDDevice *pDev) { 
          // 配置为输出引脚  HAL_write_Init(); }  void autumn_LED_Control(struct LEDDevice *pDev, int iStatus) { 
          // 设置引脚电平  HAL_GPIO_WritePin(); }  static LEDDevice g_tLEDDev = { 
          PORTA, PIN5, autumn_LED_Init, autumn_LED_Control };  int (void) { 
          pLEDDevice pLEDDev = &g_tLEDDev; pLEDDev->Init(pLEDDev); while(1) { 
          if (read_gpio_pin_key()) { 
          pLEDDev.control(pLEDDev, 1); } } } 

示例：为公司编写显示 LCD 函数

• Traditional way

void draw_logo_lcda(void)
{ 
        
	printf("display logo on lcd a\r\n");
}
void draw_logo_lcdb(void)
{ 
        
	printf("display logo on lcd b\r\n");
}

// 使用面向对象的方法

struct lcd_ops { 
        
	int type;
	void (*draw_logo)(void);
	void (*draw_text)(char *str);
};

struct lcd_ops autumn_lcds[] = { 
        
	{ 
        0, draw_logo_lcda, NULL},
	{ 
        1, draw_logo_lcdb, NULL},
	{ 
        2, draw_logo_lcdc, NULL},
	{ 
        3, draw_logo_lcdd, NULL}
};

struct lcd_ops *get_lcd_for_type(void)
{ 
        
	int i;
	int type = get_lcd_type();
	for(i = 0; i < 4; i++)
	{ 
        
		if (autumn_lcds[i].type == type)
		{ 
        
			return autumn_lcds[i];
		}
	}
	return NULL;
}

int main(void)
{ 
        
	struct lcd_ops *plcd = get_lcd_for_type();
	plcd->draw_logo();
	
	while(1);
	return 0;
}

// 只有两款LCD的情况下
int main1(void)
{ 
        
#ifndef LCD_TYPE_A
	draw_logo_lcda();
#else
	draw_logo_lcdb();
#endif
	while(1);
	
	return 0;
}
// 同时可以显示两款LCD
int main2(void)
{ 
        
	int type = get_lcd_type();
	if (type == 0)
	{ 
        
		draw_logo_lcda();
	}
	else if (type == 1)
	{ 
        
		draw_logo_lcdb();
	}
	// 如果还有很多款，那么往后继续添加 if-else 语句即可
	while(1);
	return 0;
}

对按键抽象出结构体

#define BUFFER_SIZE 10
typedef struct
{ 
        
	InputEvent buffer[BUFFER_SIZE];
	volatile unsigned int pW;
	volatile unsigned int pR;
} InputEventBuffer;

typedef enum
{ 
        
	INPUT_EVENT_TYPE_KEY,
	INPUT_EVENT_TYPE_TOUCH,
	INPUT_EVENT_TYPE_NET,
	INPUT_EVENT_TYPE_STUDIO
} INPUT_EVENT_TYPE;

typedef struct InputEvent { 
        
	TIME_T time;
	INPUT_EVENT_TYPE eType;
	int iX;
	int iY;
	int iKey;
	int iPressure;
	char str[INPUT_BUF_LEN];
} InputEvent, *pInputEvent;

typedef struct InputDevice { 
        
	char *name;
	int (*GetInputEvent)(PInputEvent ptInputEvent);
	int (*DeviceInit)(void);
	int (*DeviceExit)(void);
	struct InputDevice *pNext;
} InputDevice, *PInputDevice;