Android之service范例

第一步:新建一个Android工程，我这里命名为ServiceDemo.

第二步:修改main.xml代码，我这里增加了四个按钮,代码如下:

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<?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"    >	<TextView		android:id="@+id/text"  	    android:layout_width="fill_parent" 	    android:layout_height="wrap_content" 	    android:text="@string/hello"	    />	<Button		android:id="@+id/startservice"		android:layout_width="fill_parent"		android:layout_height="wrap_content"		android:text="startService"	/>	<Button		android:id="@+id/stopservice"		android:layout_width="fill_parent"		android:layout_height="wrap_content"		android:text="stopService"	/>	<Button		android:id="@+id/bindservice"		android:layout_width="fill_parent"		android:layout_height="wrap_content"		android:text="bindService"	/>	<Button		android:id="@+id/unbindservice"		android:layout_width="fill_parent"		android:layout_height="wrap_content"		android:text="unbindService"	/></LinearLayout>

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第三步:新建一个Service，命名为MyService.java代码如下:

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package com.tutor.servicedemo;import android.app.Service;import android.content.Intent;import android.os.Binder;import android.os.IBinder;import android.text.format.Time;import android.util.Log;public class MyService extends Service {	//定义个一个Tag标签	private static final String TAG = "MyService";	//这里定义吧一个Binder类，用在onBind()有方法里，这样Activity那边可以获取到	private MyBinder mBinder = new MyBinder();	@Override	public IBinder onBind(Intent intent) {		Log.e(TAG, "start IBinder~~~");		return mBinder;	}	@Override	public void onCreate() {		Log.e(TAG, "start onCreate~~~");		super.onCreate();	}		@Override	public void onStart(Intent intent, int startId) {		Log.e(TAG, "start onStart~~~");		super.onStart(intent, startId);		}		@Override	public void onDestroy() {		Log.e(TAG, "start onDestroy~~~");		super.onDestroy();	}			@Override	public boolean onUnbind(Intent intent) {		Log.e(TAG, "start onUnbind~~~");		return super.onUnbind(intent);	}		//这里我写了一个获取当前时间的函数，不过没有格式化就先这么着吧	public String getSystemTime(){				Time t = new Time();		t.setToNow();		return t.toString();	}		public class MyBinder extends Binder{		MyService getService()		{			return MyService.this;		}	}}

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第四步:修改ServiceDemo.java，代码如下:

package com.tutor.servicedemo;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.view.View;import android.view.View.OnClickListener;import android.widget.Button;import android.widget.TextView;public class ServiceDemo extends Activity implements OnClickListener{   	private MyService  mMyService;	private TextView mTextView;	private Button startServiceButton;	private Button stopServiceButton;	private Button bindServiceButton;	private Button unbindServiceButton;	private Context mContext;		//这里需要用到ServiceConnection在Context.bindService和context.unBindService()里用到	private ServiceConnection mServiceConnection = new ServiceConnection() {		//当我bindService时，让TextView显示MyService里getSystemTime()方法的返回值			public void onServiceConnected(ComponentName name, IBinder service) {			// TODO Auto-generated method stub			mMyService = ((MyService.MyBinder)service).getService();			mTextView.setText("I am frome Service :" + mMyService.getSystemTime());		}				public void onServiceDisconnected(ComponentName name) {			// TODO Auto-generated method stub					}	};    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.main);        setupViews();    }        public void setupViews(){        	mContext = ServiceDemo.this;    	mTextView = (TextView)findViewById(R.id.text);    	    	    	    	startServiceButton = (Button)findViewById(R.id.startservice);    	stopServiceButton = (Button)findViewById(R.id.stopservice);    	bindServiceButton = (Button)findViewById(R.id.bindservice);    	unbindServiceButton = (Button)findViewById(R.id.unbindservice);    	    	startServiceButton.setOnClickListener(this);    	stopServiceButton.setOnClickListener(this);    	bindServiceButton.setOnClickListener(this);    	unbindServiceButton.setOnClickListener(this);    }   	public void onClick(View v) {		// TODO Auto-generated method stub		if(v == startServiceButton){			Intent i  = new Intent();			i.setClass(ServiceDemo.this, MyService.class);			mContext.startService(i);		}else if(v == stopServiceButton){			Intent i  = new Intent();			i.setClass(ServiceDemo.this, MyService.class);			mContext.stopService(i);		}else if(v == bindServiceButton){			Intent i  = new Intent();			i.setClass(ServiceDemo.this, MyService.class);			mContext.bindService(i, mServiceConnection, BIND_AUTO_CREATE);		}else{			mContext.unbindService(mServiceConnection);		}	}			}

?第五步:修改AndroidManifest.xml代码(将我们新建的MyService注册进去如下代码第14行:)?

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"      package="com.tutor.servicedemo"      android:versionCode="1"      android:versionName="1.0">    <application android:icon="@drawable/icon" android:label="@string/app_name">        <activity android:name=".ServiceDemo"                  android:label="@string/app_name">            <intent-filter>                <action android:name="android.intent.action.MAIN" />                <category android:name="android.intent.category.LAUNCHER" />            </intent-filter>        </activity>		<service android:name=".MyService" android:exported="true"></service>    </application>    <uses-sdk android:minSdkVersion="7" /></manifest>&nbsp;

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第六步:执行上述工程,效果图如下:

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点击startServie按钮时先后执行了Service中onCreate()->onStart()这两个方法，打开Logcat视窗效果如下图:

我们这时可以按HOME键进入Settings(设置)->Applications(应用）->Running Services(正在运行的服务）看一下我们新启动了一个服务，效果如下:

点击stopService按钮时，Service则执行了onDestroy()方法，效果图如下所示:

这时候我们再次点击startService按钮，然后点击bindService按钮(通常bindService都是bind已经启动的Service)，我们看一下Service执行了IBinder()方法，以及TextView的值也有所变化了，如下两张图所示:

最后点击unbindService按钮，则Service执行了onUnbind()方法，如下图所示:

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