Android中Service的一个Demo例子
Service组件是Android系统重要的一部分，网上看了代码，很简单，但要想熟练使用还是需要Coding。
本文，主要贴代码，不对Service做过多讲解。
代码是从网上找的一个例子，Copy下来发现代码不完全正确，稍微修改了下。
AndroidManifest.xml
<application
android:icon="@drawable/ic_launcher"
android:label="@string/app_name" >
<activity
android:label="@string/app_name"
android:name=".service.ServiceMainActivity" >
<intent-filter >
<action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<!-- 注册Service -->
<service android:name="LocalService">
<intent-filter>
<action android:name="cn.fansunion.service.LocalService" />
</intent-filter>
</service>
</application>
ServiceMainActivity.java
package cn.fansunion.service; import cn.fansunion.R;
import android.app.Activity;
import android.app.Service;
import android.content.ComponentName;
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.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Toast; public class ServiceMainActivity extends Activity {
private Button startBtn;
private Button stopBtn;
private Button bindBtn;
private Button unBindBtn;
private static final String TAG = "MainActivity";
private LocalService myService; @Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.service);
startBtn = (Button) findViewById(R.id.start);
stopBtn = (Button) findViewById(R.id.stop);
bindBtn = (Button) findViewById(R.id.bind);
unBindBtn = (Button) findViewById(R.id.unbind);
startBtn.setOnClickListener(new MyOnClickListener());
stopBtn.setOnClickListener(new MyOnClickListener());
bindBtn.setOnClickListener(new MyOnClickListener());
unBindBtn.setOnClickListener(new MyOnClickListener());
} class MyOnClickListener implements OnClickListener {
@Override
public void onClick(View v) {
Intent intent = new Intent();
intent.setClass(ServiceMainActivity.this, LocalService.class);
switch (v.getId()) {
case R.id.start:
// 启动Service
startService(intent);
toast("startService");
break;
case R.id.stop:
// 停止Service
stopService(intent);
toast("stopService");
break;
case R.id.bind:
// 绑定Service
bindService(intent, conn, Service.BIND_AUTO_CREATE);
toast("bindService");
break;
case R.id.unbind:
// 解除Service
unbindService(conn);
toast("unbindService");
break;
}
}
} private void toast(final String tip){
runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(getApplicationContext(), tip, Toast.LENGTH_SHORT).show();
}
});
}
private ServiceConnection conn = new ServiceConnection() {
@Override
public void onServiceConnected(ComponentName name, IBinder service) {
Log.e(TAG, "连接成功");
// 当Service连接建立成功后，提供给客户端与Service交互的对象（根据Android Doc翻译的，不知道准确否。。。。）
myService = ((LocalService.LocalBinder) service).getService();
} @Override
public void onServiceDisconnected(ComponentName name) {
Log.e(TAG, "断开连接");
myService = null;
}
};
}
LocalService.java
package cn.fansunion.service; import android.app.Service;
import android.content.Intent;
import android.os.Binder;
import android.os.IBinder;
import android.util.Log;
import android.widget.Toast; public class LocalService extends Service {
private static final String TAG = "MyService";
private final IBinder myBinder = new LocalBinder(); @Override
public IBinder onBind(Intent intent) {
Log.e(TAG, "onBind()");
//Toast.makeText(this, "onBind()", Toast.LENGTH_SHORT).show();
return myBinder;
} // 调用startService方法或者bindService方法时创建Service时（当前Service未创建）调用该方法
@Override
public void onCreate() {
Log.e(TAG, "onCreate()");
//Toast.makeText(this, "onCreate()", Toast.LENGTH_SHORT).show();
} // 调用startService方法启动Service时调用该方法
@Override
public void onStart(Intent intent, int startId) {
Log.e(TAG, "onStart()");
//Toast.makeText(this, "onStart()", Toast.LENGTH_SHORT).show();
} // Service创建并启动后在调用stopService方法或unbindService方法时调用该方法
@Override
public void onDestroy() {
Log.e(TAG, "onDestroy()");
//Toast.makeText(this, "onDestroy()", Toast.LENGTH_SHORT).show();
}
//提供给客户端访问
public class LocalBinder extends Binder {
LocalService getService() {
return LocalService.this;
}
}
}
service.xml布局文件
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="fill_parent"
android:layout_height="fill_parent">
<Button android:id="@+id/start" android:layout_width="wrap_content"
android:layout_height="wrap_content" android:text="启动Service" />
<Button android:id="@+id/stop" android:layout_width="wrap_content"
android:layout_height="wrap_content" android:text="停止Service" />
<Button android:id="@+id/bind" android:layout_width="wrap_content"
android:layout_height="wrap_content" android:text="绑定Service" />
<Button android:id="@+id/unbind" android:layout_width="wrap_content"
android:layout_height="wrap_content" android:text="解除Service" />
</LinearLayout>
[2015-11-14 17:39:10 - xp2p4android] ------------------------------
[2015-11-14 17:39:10 - xp2p4android] Android Launch!
[2015-11-14 17:39:10 - xp2p4android] adb is running normally.
[2015-11-14 17:39:10 - xp2p4android] Performing cn.fansunion.service.ServiceMainActivity activity launch
[2015-11-14 17:39:10 - xp2p4android] Automatic Target Mode: using device '51bf63f2'
[2015-11-14 17:39:10 - xp2p4android] Uploading xp2p4android.apk onto device '51bf63f2'
[2015-11-14 17:39:10 - xp2p4android] Installing xp2p4android.apk...
[2015-11-14 17:39:13 - xp2p4android] Success!
[2015-11-14 17:39:13 - xp2p4android] Starting activity cn.fansunion.service.ServiceMainActivity on device 51bf63f2
[2015-11-14 17:39:13 - xp2p4android] ActivityManager: Starting: Intent { act=android.intent.action.MAIN cat=[android.intent.category.LAUNCHER] cmp=cn.fansunion/.service.ServiceMainActivity }
[2015-11-14 17:39:13 - xp2p4android] Attempting to connect debugger to 'cn.fansunion' on port 8600
运行效果图
原来的代码，Toast对话框没有展示出来。
在CSDN论坛找到一个贴子说，可能是被手机屏蔽了。
我倒是觉得更有可能调用的方式不对。
Service中调用，Toast合适么？
public void onCreate() {
Log.e(TAG, "onCreate()");
//Toast.makeText(this, "onCreate()", Toast.LENGTH_SHORT).show();
}
最后参考网友的办法，在UI线程，新建线程执行Toast。
private void toast(final String tip){
runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(getApplicationContext(), tip, Toast.LENGTH_SHORT).show();
}
});
}
不错，是在Activity中调用的。
这充分说明，网上代码再漂亮，还是得动手运行下。
代码的那个贴子，是2011年了，好古老啊~
参考资料
Android中Service组件详解
http://blog.csdn.net/zuolongsnail/article/details/6427037
Android Toast显示不出来
http://bbs.csdn.net/topics/390889540