該方法前提是三方應用必須打入系統應用，並且在應用程式的AndroidManifest.xml中的manifest節點中加入android:sharedUserId="android.uid.system"這個屬性。

static String RED_LED_DEV = "/sys/class/leds/red/brightness";  
static String GREEN_LED_DEV = "/sys/class/leds/green/brightness";  
static String BLUE_LED_DEV = "/sys/class/leds/blue/brightness";  
  
static void setLedStatus (String ledDev, boolean setStatusOn) {  
	try {  
		FileOutputStream fLed = new FileOutputStream(ledDev);  
		fLed.write((setStatusOn ? "255" : "0").getBytes());  
		fLed.close();  
	} catch (Exception e) {  
		e.printStackTrace();   
	}  
}