Service IntentService Android中的线程 MediaPlayer
在Service中添加线程
注意服务是需要注册的
public class MyService extends Service {
private int count;
@Override
public void onCreate() {
super.onCreate();
Log.d("", "onCreate");
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
Log.d("","onStartCommand");
new Thread(new Runnable() {
@Override
public void run() {
while (count<100){
count++;
Intent intent = new Intent();
intent.setAction(MainActivity.DOWN_LOAD_ACTION);
intent.putExtra("count", count);
sendBroadcast(intent);
try {
Thread.sleep(200);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}).start();
return super.onStartCommand(intent, flags, startId);
}
@Override
public void onDestroy() {
super.onDestroy();
Log.d("", "onDestroy");
}
@Override
public IBinder onBind(Intent intent) {
return null;
}
}public class MainActivity extends Activity implements View.OnClickListener {
public static final String DOWN_LOAD_ACTION ="com.service.test" ;
private ProgressBar mProgressbar;
private Button mButtonDownload;
private Button mButtonStop;
private MyReceiver myReceiver;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
myReceiver = new MyReceiver();
IntentFilter filter = new IntentFilter();
filter.addAction(DOWN_LOAD_ACTION);
registerReceiver(myReceiver, filter);
mProgressbar = (ProgressBar) findViewById(R.id.progressbar_download);
mProgressbar.setOnClickListener(this);
mButtonDownload = (Button) findViewById(R.id.button_download);
mButtonStop = (Button) findViewById(R.id.button_stop);
mButtonDownload.setOnClickListener(this);
mButtonStop.setOnClickListener(this);
}
@Override
public void onClick(View view) {
switch (view.getId()){
case R.id.button_stop:
Intent intent1 = new Intent(getApplicationContext(),MyIntentService.class);
stopService(intent1);
break;
case R.id.button_download:
Intent intent = new Intent(getApplicationContext(),MyIntentService.class);
startService(intent);
break;
default:
break;
}
}
@Override
protected void onDestroy() {
super.onDestroy();
unregisterReceiver(myReceiver);
}
public class MyReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
int count = intent.getIntExtra("count",0);
mProgressbar.setProgress(count);
}
}
}利用IntentService添加线程，因为其自身包含一个线程，所以不用new Thread一个线程
public class MyIntentService extends IntentService {
private int count;
public MyIntentService(String name) {
super(name);//调用父类的有参构造函数
}
public MyIntentService(){
this("");
}
@Override
public void onDestroy() {
super.onDestroy();
Log.d("MyIntentService","服务关闭");
}
@Override
protected void onHandleIntent(Intent intent) {
Log.d("MyIntentService","运行到IntentService");
while (true){
if (count>100){
count=0;
}
count++;
Intent intent2 = new Intent();
intent2.setAction(MainActivity.DOWN_LOAD_ACTION);
intent2.putExtra("count", count);
sendBroadcast(intent2);
try {
Thread.sleep(200);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}Android中的进程、线程
加入新的进程有两种方法handler asynctask
handler
子线程给主线程发消息
方法一：
public class MainActivity extends Activity {
private Button mButton;
private int count = 60;
public static final int TIME_DESC =0x23 ;
private MyHandler handler = new MyHandler();
class MyHandler extends Handler{
@Override
public void handleMessage(Message msg) {
switch (msg.what){
case TIME_DESC:
count--;
mButton.setText(count+"秒");
if (count>0){
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
handler.sendEmptyMessage(TIME_DESC);
}
break;
}
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mButton = (Button) findViewById(R.id.button);
mButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
count = 60;
handler.sendEmptyMessage(TIME_DESC);
}
});
}
}方法二：
public class MainActivity extends Activity {
private Button mButton;
private int count = 60;
public static final int TIME_DESC =0x23 ;
private MyHandler handler = new MyHandler();
class MyHandler extends Handler{
@Override
public void handleMessage(Message msg) {
switch (msg.what){
case TIME_DESC:
String time = (String) msg.obj;
mButton.setText(time);
break;
}
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mButton = (Button) findViewById(R.id.button);
mButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
count = 60;
new Thread(new Runnable() {
@Override
public void run() {
while (count>0){
count--;
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
Message msg = new Message();
msg.obj = count+"秒";
msg.what = TIEM_DESC;
handler.sendMessage(msg);
}
}
}).start();
}
});
}
}主线程给子线程发消息
基本不这么用，
public class MainActivity extends Activity {
private Button mButton;
private Button mButton2;
private int count = 60;
public static final int TIME_DESC =0x23 ;
private Handler handler;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mButton = (Button) findViewById(R.id.button);
mButton2 = (Button) findViewById(R.id.button2);
mButton2.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
handler.sendEmptyMessage(0);
}
});
mButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
count = 60;
MyThread thread = new MyThread();
thread.start();
}
});
}
class MyThread extends Thread{
@Override
public void run() {
Looper.prepare();
handler = new Handler(){
@Override
public void handleMessage(Message msg) {
Log.d("handler","接受主线程的消息");
super.handleMessage(msg);
}
};
Looper.loop();
}
}
}AsyncTask
public class MainActivity extends Activity {
private Button mButton;
private ProgressBar mProgressbar;
private int count = 0;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mButton = (Button) findViewById(R.id.button);
mProgressbar = (ProgressBar) findViewById(R.id.progressbar);
mButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
MyTast tast = new MyTast();
tast.execute("去执行");//用execute()方法调用
}
});
}
class MyTast extends AsyncTask{
@Override
protected void onPostExecute(String s) {//运行结束
super.onPostExecute(s);
mButton.setText(s);
}
@Override
protected void onProgressUpdate(String... values) {//中间运行
super.onProgressUpdate(values);
int count = Integer.parseInt(values[0]);
mProgressbar.setProgress(count);
}
@Override
protected String doInBackground(String... strings) {//开始运行
while (count<101){
count++;
publishProgress(""+count);
try {
Thread.sleep(200);
} catch (InterruptedException e) {
e.printStackTrace();
}
Log.d("",""+count);
}
return "执行结束";//返回onPostExecute 中的s值
}
}
} MediaPlayer
public class MainActivity extends Activity {
private Button mButtonStartMusic;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mButtonStartMusic = (Button) findViewById(R.id.button_music);
mButtonStartMusic.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
MediaPlayer mediaPlayer = new MediaPlayer();
mediaPlayer.reset();
Log.d("","文件路径"+Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_MUSIC));
File musicDir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_MUSIC);
File[] files = musicDir.listFiles();
try {
mediaPlayer.setDataSource(files[0].getAbsolutePath());
mediaPlayer.prepare();
mediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
@Override
public void onPrepared(MediaPlayer mediaPlayer) {
mediaPlayer.start();
}
});
} catch (IOException e) {
e.printStackTrace();
}
}
});
}
}