1. Service的启动方式有startServcie和bindService两种。
startService时，会经历onCreate—onStartCommand—onDestroy生命周期，
bindService时，会经历onCreate—onBind—onUnbind—onDestroy生命周期。
2. Service与Activity之间交互时，可以通过bindService获取Service的连接的Binder，进而可以获取Service的引用，这样就可以与Service进行交互了。示例中，通过Service每秒更新TextView一次。
ICounterCallback接口
package com.fxb.servicetest;
public interface ICounterCallback {
public void count(int val);
}
CountService类
package com.fxb.servicetest; import android.app.Service;
import android.content.Intent;
import android.os.AsyncTask;
import android.os.Binder;
import android.os.IBinder;
import android.support.annotation.Nullable;
import android.util.Log; public class CountService extends Service{ private volatile boolean isRunning = true;
private CounterBinder counterBinder = new CounterBinder(); @Nullable
@Override
public IBinder onBind(Intent intent) {
Log.i(MainActivity.TAG, "on bind!");
return counterBinder;
} public void startCounter(final int value, final ICounterCallback callback){
isRunning = true;
new AsyncTask<Integer, Integer, Void>() {
@Override
protected Void doInBackground(Integer... params) {
int count = params[0];
while(isRunning){
try {
Thread.sleep(1000);
count++;
Log.i(MainActivity.TAG, Integer.toString(count));
publishProgress(count);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
return null;
} @Override
protected void onProgressUpdate(Integer... values) {
super.onProgressUpdate(values);
callback.count(values[0]);
}
}.execute(0);
} public void stopCounter(){
isRunning = false;
} @Override
public void onCreate() {
super.onCreate();
Log.i(MainActivity.TAG, "on create!");
} @Override
public int onStartCommand(Intent intent, int flags, int startId) {
Log.i(MainActivity.TAG, "on start command!");
return super.onStartCommand(intent, flags, startId);
} @Override
public boolean onUnbind(Intent intent) {
Log.i(MainActivity.TAG, "on unbind servcie!");
return super.onUnbind(intent);
} @Override
public void onDestroy() {
isRunning = false;
Log.i(MainActivity.TAG, "on destroy service");
super.onDestroy();
} @Override
public boolean stopService(Intent name) {
Log.i(MainActivity.TAG, "on stop service!");
return super.stopService(name);
} public class CounterBinder extends Binder{
public CountService getService(){
return CountService.this;
}
}
}
MainActivity类
package com.fxb.servicetest; import android.app.Activity;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.ServiceConnection;
import android.os.Bundle;
import android.os.IBinder;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView; public class MainActivity extends Activity implements View.OnClickListener, ICounterCallback{ public static final String TAG = "ServiceTest"; private TextView tvShow;
private Button btnStartServie, btnStopService;
private Button btnBindService, btnUnbindService;
private Button btnStartCounter, btnStopCounter;
private CountService countService; @Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initView();
} private void initView(){
tvShow = (TextView)findViewById(R.id.tvShow);
btnStartServie = (Button)findViewById(R.id.btnStartService);
btnStopService = (Button)findViewById(R.id.btnStopService);
btnBindService = (Button)findViewById(R.id.btnBindService);
btnUnbindService = (Button)findViewById(R.id.btnUnbindService);
btnStartCounter = (Button)findViewById(R.id.btnStartCount);
btnStopCounter = (Button)findViewById(R.id.btnStopCount); btnStartServie.setOnClickListener(this);
btnStopService.setOnClickListener(this);
btnBindService.setOnClickListener(this);
btnUnbindService.setOnClickListener(this);
btnStartCounter.setOnClickListener(this);
btnStopCounter.setOnClickListener(this);
} private void startCountService(){
Intent intent = new Intent(MainActivity.this, CountService.class);
startService(intent);
} private void stopCountService(){
Intent intent = new Intent(MainActivity.this, CountService.class);
stopService(intent);
} private void myBindService(){
Intent intent = new Intent(MainActivity.this, CountService.class);
bindService(intent, serviceConnection, Context.BIND_AUTO_CREATE);
} private void myUnbindService(){
unbindService(serviceConnection);
} @Override
public void onClick(View v) {
if(v == btnStartServie){
Log.i(TAG, "start click");
startCountService();
}
else if(v == btnStopService){
stopCountService();
}
else if(v == btnBindService){
myBindService();
}
else if(v == btnUnbindService){
myUnbindService();
}
else if(v == btnStartCounter){
if(countService != null){
countService.startCounter(0, this);
}
}
else if(v == btnStopCounter){
if(v == btnStopCounter){
countService.stopCounter();
}
}
} @Override
public void count(int val) {
tvShow.setText("count:"+val);
} private ServiceConnection serviceConnection = new ServiceConnection() {
@Override
public void onServiceConnected(ComponentName name, IBinder service) {
Log.i(MainActivity.TAG, "service connected!");
CountService.CounterBinder binder = (CountService.CounterBinder)service;
countService = binder.getService();
} @Override
public void onServiceDisconnected(ComponentName name) {
Log.i(MainActivity.TAG, "service disconnected!");
}
}; }
在bindService之后，点击startCount后，tvShow每隔1s更新一次，点击stopCount后停止更新。