String strA = "hi";
strA = "hello";

Integer iA = 100;
Integer iB = 100;
System.out.println(iA==iB); // true


Integer iA = 128;
Integer iB = 128;
System.out.println(iA==iB); // false


Integer iA = new Integer(100);
Integer iB = new Integer(100);
System.out.println(iA==iB); // false

int iA = 128;
int iB = 128;
System.out.println(iA==iB); // true

1. 5V：供電的(+)
2. TX：傳送訊號
3. RX：接收訊號
4. GND：接地線(-)

int iLedPin        = 13;
void setup(){
  // define the PIN as OUTPUT 
  pinMode(iLedPin        ,OUTPUT);  
  
  // using baud rate 9600 to listen.
  Serial.begin(9600);
}

void loop(){
  while (Serial.available()){
    char cCmd = Serial.read();
    if (cCmd =='o'){
      digitalWrite(iLedPin,HIGH);
    }else if (cCmd == 'c'){
      digitalWrite(iLedPin,LOW);
    }
  }
}

sudo cu -s 9600 -l /dev/tty.KENarduino-DevB 

Connected

• startService
• bindService

1. Android C2DM (四)：實作之Android篇
2. android detect screen on and screen off
3. android 偵測 sdcard

Once started, a service can run in the background indefinitely, even if the component that started it is destroyed. Usually, a started service performs a single operation and does not return a result to the caller. For example, it might download or upload a file over the network. When the operation is done, the service should stop itself.

A bound service offers a client-server interface that allows components to interact with the service, send requests, get results, and even do so across processes with interprocess communication (IPC). A bound service runs only as long as another application component is bound to it. Multiple components can bind to the service at once, but when all of them unbind, the service is destroyed.

public class Services extends Service {

 @Override
 public IBinder onBind(Intent intent) {
  // TODO Auto-generated method stub
  Log.d("TestService","onBind");
  return null;
 }
 
 @Override
 public int onStartCommand(Intent intent, int flags, int startId) {
  Log.d("TestService","onStartCommand");
  return super.onStartCommand(intent, flags, startId);
 }
 @Override
 public ComponentName startService(Intent service) {
  Log.d("TestService","startService");
  return super.startService(service);
 }
 
 @Override
 public void onCreate() {
  super.onCreate();
  Log.d("TestService","onCreate");
 }
 
 @Override
 public void onDestroy() {
  super.onDestroy();
  Log.d("TestService","onDestroy");
 }

 @Override
 public boolean onUnbind(Intent intent) {
  Log.d("TestService","onUnbind");
  return super.onUnbind(intent);
 }
 
}

@Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  
  startService(new Intent(this,Services.class));
 }

@Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  
  bindService(new Intent(this,Services.class),null,Context.BIND_AUTO_CREATE);
 }