服务Service，并与活动、接收器之间的通信
配置文件声明：
。。。
1.Service
/**
* 1.服务需要在配置文件中声明。
* 2.启动服务使用Intent。
* 3.服务自行停止，只需要在MyService任何一个位置调用stopSelf()方法就行了。
* 4.任何一个服务在整个应用程序范围内都是通用的，
* 及MyService可以和任何一个活动进行绑定，
* 而且在绑定完成后它们都可以获取到相同的DownloadBinder实例。
* 5.当一个服务既被启动又被绑定后，需要同时调用stopService()和unbindService()方法，
* onDestroy()才会执行。
*/
public class MyService extends Service{
private DownloadBinder downloadBinder = new DownloadBinder();
@Nullable
@Override
public IBinder onBind(Intent intent) {
return downloadBinder;
}
/**
* 服务第一次创建的时候调用
*/
@Override
public void onCreate() {
super.onCreate();
ToastUtil.showMessage("服务创建");
/*//创建一个前台服务
Intent intent = new Intent(this, MainActivity.class);
PendingIntent pendingIntent = PendingIntent.getActivity(this,0,intent,0);
NotificationCompat.Builder builder = new NotificationCompat.Builder(this)
//设置小图标
.setSmallIcon(R.mipmap.ic_launcher)
//设置通知标题
.setContentTitle("最简单的Notification")
//设置点击后事件
.setContentIntent(pendingIntent)
//设置通知内容
.setContentText("只有小图标、标题、内容");
Notification notification = builder.build();
startForeground(1, notification);*/
}
/**
* 每次服务启动的时候都会调用
* @param intent
* @param flags
* @param startId
* @return
*/
@Override
public int onStartCommand(Intent intent,int flags, int startId) {
ToastUtil.showMessage("服务启动");
/*new Thread(new Runnable() {
@Override
public void run() {
//让服务执行完毕后自动停止
stopSelf();
}
});*/
return super.onStartCommand(intent, flags, startId);
}
@Override
public void onDestroy() {
super.onDestroy();
ToastUtil.showMessage("服务销毁");
}
class DownloadBinder extends Binder{
public void startDownload(){
ToastUtil.showMessage("开始下载");
}
public int getProgress(){
ToastUtil.showMessage("下载进度");
return 0;
}
}
}
2.IntentService
public class MyIntentService extends IntentService{
public MyIntentService() {
super("MyIntentService");//调用父类的有参构造函数
}
/**
* 处理一些具体的逻辑，运行在子线程中
* @param intent
*/
@Override
protected void onHandleIntent(@Nullable Intent intent) {
//显示当前线程的id
ToastUtil.showMessage("MyIntentService当前线程的id：" + Thread.currentThread().getId());
}
@Override
public void onDestroy() {
super.onDestroy();
ToastUtil.showMessage("MyIntentService销毁");
}
}
3.Service与BroadcastReceiver
LongRunningService ：
/**
* 一旦启动LongRunningService，就会在onStartCommand方法里设定一个定时任务，
* 3秒后AlarmReceiver的onReceive方法就会得到执行，
* 然后又在里面再次启动LongRunningService，这样就形成了一个永久的循环，
* 保证LongRunningService可以每隔3秒就会启动一次。
*/
public class LongRunningService extends Service{
@Nullable
@Override
public IBinder onBind(Intent intent) {
return null;
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
Log.d("LongRunningService","onStartCommand");
new Thread(new Runnable() {
@Override
public void run() {
Log.d("LongRunningService",new Date().toString());
}
}).start();
AlarmManager alarmManager = (AlarmManager) getSystemService(ALARM_SERVICE);
int date = 3 * 1000;//3秒
long triggerAtTime = SystemClock.elapsedRealtime() + date;
Intent intent1 = new Intent(this,AlarmReceiver.class);
PendingIntent pendingIntent = PendingIntent.getBroadcast(this, 0, intent1, 0);
alarmManager.set(AlarmManager.ELAPSED_REALTIME_WAKEUP, triggerAtTime, pendingIntent);
return super.onStartCommand(intent, flags, startId);
}
}
AlarmReceiver ：
public class AlarmReceiver extends BroadcastReceiver{
@Override
public void onReceive(Context context, Intent intent) {
Log.d("AlarmReceiver","onReceive");
Intent intent1 = new Intent(context, LongRunningService.class);
context.startService(intent1);
}
}
4.活动：
布局：添加几个按钮。
public class MainActivity extends AppCompatActivity {
@BindView(R.id.btn_start_service)
Button btnStartService;
@BindView(R.id.btn_stop_service)
Button btnStopService;
@BindView(R.id.btn_bind_service)
Button btnBindService;
@BindView(R.id.btn_unbind_service)
Button btnUnbindService;
@BindView(R.id.btn_start_intent_service)
Button btnStartIntentService;
@BindView(R.id.btn_start_long_running_service)
Button btnStartLongRunningService;
private MyService.DownloadBinder downloadBinder;
private ServiceConnection connection = new ServiceConnection() {
//服务成功绑定的时候调用
@Override
public void onServiceConnected(ComponentName name, IBinder service) {
downloadBinder = (MyService.DownloadBinder) service;
downloadBinder.startDownload();
downloadBinder.getProgress();
}
//服务解绑的时候调用
@Override
public void onServiceDisconnected(ComponentName name) {
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ButterKnife.bind(this);
}
@OnClick({R.id.btn_start_service, R.id.btn_stop_service,
R.id.btn_bind_service, R.id.btn_unbind_service,
R.id.btn_start_intent_service,
R.id.btn_start_long_running_service})
public void onViewClicked(View view) {
Intent intent = null;
switch (view.getId()) {
case R.id.btn_start_service://启动服务
intent = new Intent(MainActivity.this, MyService.class);
startService(intent);
break;
case R.id.btn_stop_service://停止服务
intent = new Intent(MainActivity.this, MyService.class);
stopService(intent);
break;
case R.id.btn_bind_service://绑定服务
intent = new Intent(MainActivity.this, MyService.class);
bindService(intent, connection, BIND_AUTO_CREATE);
//BIND_AUTO_CREATE表示在活动和服务进行绑定后自动创建服务，
//这会使得MyService的onCreate方法得到执行，但onStartCommand方法不会执行。
break;
case R.id.btn_unbind_service://解绑服务
unbindService(connection);
break;
case R.id.btn_start_intent_service:
ToastUtil.showMessage("MainActivity当前线程的id：" + Thread.currentThread().getId());
intent = new Intent(MainActivity.this, MyIntentService.class);
startService(intent);
break;
case R.id.btn_start_long_running_service:
intent = new Intent(MainActivity.this, LongRunningService.class);
startService(intent);
break;
}
}
}