android入门——Service

简单记录一下四大组件之一的Service的简单实用。

先是最简单的用法，服务的开关，onBind方法的使用

package com.example.wkp.service;

import android.content.ComponentName;
import android.content.Intent;
import android.content.ServiceConnection;
import android.os.IBinder;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;

public class MainActivity extends AppCompatActivity {
    private Button start=null;
    private Button stop=null;
    private Button bind=null;
    private Button unbind=null;
    private Button get=null;
    private MyService.MyBinder binder;
    private ServiceConnection connection=new ServiceConnection() {
        @Override
        public void onServiceConnected(ComponentName name, IBinder service) {
            //得到返回值binder
            binder= (MyService.MyBinder) service;
            //使用binder中的方法
            Log.v("qq",String.valueOf(binder.getNum()));
        }

        @Override
        public void onServiceDisconnected(ComponentName name) {

        }
    };
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        start= (Button) findViewById(R.id.start);
        stop=(Button)findViewById(R.id.stop);
        bind=(Button)findViewById(R.id.bind);
        unbind=(Button)findViewById(R.id.unbind);
        get=(Button)findViewById(R.id.getnum);

        final Intent intent=new Intent();
        //跳转到配置文件中定义的intent-filter
//        intent.setAction("SERVICE");
//        intent.setPackage(getPackageName());
        intent.setClass(MainActivity.this,MyService.class);

        start.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                startService(intent);
            }
        });

        stop.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                stopService(intent);
            }
        });

        bind.setOnClickListener(new View.OnClickListener(){

            @Override
            public void onClick(View v) {
                bindService(intent,connection,BIND_AUTO_CREATE);
            }
        });

        unbind.setOnClickListener(new View.OnClickListener(){

            @Override
            public void onClick(View v) {
                unbindService(connection);
            }
        });

        get.setOnClickListener(new View.OnClickListener(){

            @Override
            public void onClick(View v) {
                Log.v("qq",String.valueOf(binder.getNum()));
            }
        });


//        class btnListener implements View.OnClickListener{
//
//            @Override
//            public void onClick(View v) {
//                switch(v.getId()){
//                    case R.id.bind:
//                        bindService(intent,connection,BIND_AUTO_CREATE);
//                        break;
//                    case R.id.unbind:
//                        unbindService(connection);
//                        break;
//                    case R.id.getnum:
//                        Log.v("qq",String.valueOf(binder.getNum()));
//                        break;
//                    default:
//                        break;
//                }
//            }
//        }
    }
}

MainActivity.java

package com.example.wkp.service;

import android.app.Service;
import android.content.Intent;
import android.os.Binder;
import android.os.IBinder;
import android.support.annotation.Nullable;
import android.util.Log;
import android.widget.Button;

/**
 * Created by wkp on 2016/9/22.
 */
public class MyService extends Service {

    int num=0;
    MyBinder binder=new MyBinder();

    @Nullable
    @Override
    public IBinder onBind(Intent intent) {
        Log.v("oo","binder");
        return binder;
    }

    @Override
    public void onCreate() {
        super.onCreate();
        Log.v("hehe","service create");
        num+=10;
    }

    @Override
    public void onStart(Intent intent, int startId) {
        super.onStart(intent, startId);
        Log.v("hehe","service start");
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        Log.v("hehe","service destory");
    }

    //创建一个Binder,用来在onBind中返回
    class MyBinder extends Binder{
        int getNum(){
            return num;
        }
    }
}

MyService.java

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.example.wkp.service.MainActivity">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World!" />

    <Button android:id="@+id/start"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="start"/>

    <Button android:id="@+id/stop"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="stop"/>

    <Button android:id="@+id/bind"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="bind"/>

    <Button android:id="@+id/unbind"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="unbind"/>

    <Button android:id="@+id/getnum"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="getnum"/>
</LinearLayout>

activity_main.xml

在AndroidManifest.xml中注册服务

然后是前台服务和IntentService。就是手机屏幕左上角弹出来的小图标，和广播结合有点类似推送。

package com.example.wkp.service;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

/**
 * Created by wkp on 2016/9/24.
 */
public class SecondActivity extends Activity {

    private Button startFore=null;
    private Button stopFore=null;
    private Button startIntent=null;
    private Button stopIntent=null;
    private Intent intent1,intent2=null;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_second);
        init();
        intent1=new Intent(SecondActivity.this,MyService2.class);
        intent2=new Intent(SecondActivity.this,MyIntentService.class);
    }

    //按钮控件初始化
    void init(){
        startFore= (Button) findViewById(R.id.startFore);
        stopFore=(Button)findViewById(R.id.startFore);
        startIntent=(Button) findViewById(R.id.startIntent);
        stopIntent=(Button) findViewById(R.id.stopIntent);

        startFore.setOnClickListener(new btnListener());
        stopFore.setOnClickListener(new btnListener());
        startIntent.setOnClickListener(new btnListener());
        stopIntent.setOnClickListener(new btnListener());
    }

    class btnListener implements View.OnClickListener{

        @Override
        public void onClick(View v) {
            switch(v.getId()){
                case R.id.startFore:
                    startService(intent1);
                    break;
                case R.id.stopFore:
                    break;
                case R.id.startIntent:
                    startService(intent2);
                    break;
                case R.id.stopIntent:
                    stopService(intent2);
                    break;
                default:break;
            }
        }
    }
}

SecondActivity.java

package com.example.wkp.service;

import android.app.Notification;
import android.app.PendingIntent;
import android.app.Service;
import android.content.Intent;
import android.os.IBinder;
import android.support.annotation.Nullable;
import android.widget.RemoteViews;

/**
 * Created by wkp on 2016/9/24.
 */
public class MyService2 extends Service{
    @Nullable
    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }

    @Override
    public void onCreate() {
        super.onCreate();
        //创建通知实例
        Notification notification=new Notification();
        //图标
        notification.icon=R.drawable.books;
        //内容
        notification.contentView=new RemoteViews(getPackageName(),R.layout.notify);
        //跳转
        notification.contentIntent= PendingIntent.getActivity(this,0,new Intent(this,SecondActivity.class),0);
        //开启
        startForeground(1,notification);
    }
}

MyService2.java

package com.example.wkp.service;

import android.app.IntentService;
import android.app.Service;
import android.content.Intent;
import android.os.IBinder;
import android.support.annotation.Nullable;
import android.util.Log;

/**
 * Created by wkp on 2016/9/24.
 */
public class MyIntentService extends IntentService{

    /**
     * Creates an IntentService.  Invoked by your subclass's constructor.
     *
     * @param name Used to name the worker thread, important only for debugging.
     */
    public MyIntentService(String name) {
        super(name);
    }

    //必须创建一个无参的构造方法
    public MyIntentService(){
        super("MyIntentService");
    }

    //开启一个新的线程，可以进行耗时操作
    @Override
    protected void onHandleIntent(Intent intent) {
        Log.v("haha","onhandle");
        Log.v("hehe",String.valueOf(Thread.currentThread().getId()));
        Log.v("hehe",String.valueOf(android.os.Process.myPid()));
        while(true){
            try{
                Thread.sleep(1000);
                Log.v("pp","I am in handle");
            }catch(Exception e){
                e.printStackTrace();
            }

        }
    }

    @Override
    public void onCreate() {
        super.onCreate();
        Log.v("haha","oncreate");
        Log.v("hehe",String.valueOf(Thread.currentThread().getId()));
        Log.v("hehe",String.valueOf(android.os.Process.myPid()));
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        Log.v("haha","ondestroy");
        Log.v("hehe",String.valueOf(Thread.currentThread().getId()));
        Log.v("hehe",String.valueOf(android.os.Process.myPid()));
    }
}

MyIntentService.java

Service和IntentService的区别是后者开启新的线程可以进行耗时操作。

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent">

    <Button android:id="@+id/startFore"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="startFore"/>

    <Button android:id="@+id/stopFore"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="stopFore"/>

    <Button android:id="@+id/startIntent"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="startIntent"/>

    <Button android:id="@+id/stopIntent"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="stopIntent"/>
</LinearLayout>

activity_second.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent">

    <ImageView
        android:src="@drawable/books"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="前台服务"/>
</LinearLayout>

notify.xml

最后Service和Broadcast Receiver结合做一个定点报时

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.wkp.clock">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

        <service android:name=".AlarmService">

        </service>

        <receiver android:name=".AlarmReceiver">
            <intent-filter>
                <action android:name="ALARM_ACTION" />
            </intent-filter>
        </receiver>
    </application>

</manifest>

AndroidManifest.xml

package com.example.wkp.clock;

import android.content.ComponentName;
import android.content.Intent;
import android.content.ServiceConnection;
import android.os.IBinder;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

public class MainActivity extends AppCompatActivity {

    private Button start=null;
    private Button stop=null;
    private EditText edit=null;
    private Intent intent = null;
    private AlarmService.AlarmBinder binder;

    private ServiceConnection connection=new ServiceConnection() {
        @Override
        public void onServiceConnected(ComponentName name, IBinder service) {
            binder=(AlarmService.AlarmBinder)service;
        }

        @Override
        public void onServiceDisconnected(ComponentName name) {

        }
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        init();
    }

    void init(){
        start= (Button) findViewById(R.id.start);
        stop= (Button) findViewById(R.id.stop);
        edit=(EditText)findViewById(R.id.edit);

        start.setOnClickListener(new btnListener());
        stop.setOnClickListener(new btnListener());

        //绑定服务
        intent=new Intent(this,AlarmService.class);
        bindService(intent,connection,BIND_AUTO_CREATE);
    }

    class btnListener implements View.OnClickListener{

        @Override
        public void onClick(View v) {
            switch (v.getId()){
                case R.id.start:
                    binder.setTime(Integer.parseInt(edit.getText().toString()));
                    startService(intent);
                    break;
                case R.id.stop:
                    binder.setState();
                    break;
                default:
                    break;
            }
        }
    }
}

MainActivity.java

package com.example.wkp.clock;

import android.app.AlarmManager;
import android.app.Notification;
import android.app.PendingIntent;
import android.app.Service;
import android.content.Intent;
import android.os.Binder;
import android.os.IBinder;
import android.os.SystemClock;
import android.support.annotation.Nullable;
import android.util.Log;
import android.widget.RemoteViews;

/**
 * Created by wkp on 2016/9/24.
 */
public class AlarmService extends Service {

    private AlarmBinder binder = new AlarmBinder();
    private AlarmManager manager;
    private Intent intent1;
    private PendingIntent pd;
    private int time;
    private boolean flag=true;

    @Nullable
    @Override
    public IBinder onBind(Intent intent) {

        //得到manager
        manager = (AlarmManager) getSystemService(ALARM_SERVICE);
        intent1 = new Intent(this, AlarmReceiver.class);
        intent1.setAction("ALARM_ACTION");
        //得到PendingIntent
        pd = PendingIntent.getBroadcast(this, 0, intent1, 0);
        return binder;
    }

    @Override
    public void onCreate() {
        super.onCreate();
        //创建通知实例
        Notification notification = new Notification();
        //图标
        notification.icon = R.drawable.books;
        //内容
        notification.contentView = new RemoteViews(getPackageName(), R.layout.notify);
        //跳转
        notification.contentIntent = PendingIntent.getActivity(this, 0, new Intent(this, MainActivity.class), 0);
        //开启
        startForeground(1, notification);
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        //设置闹钟
        //类型，开机到现在的时间||1970.1.1到现在的时间||。。。wakeup唤醒CPU
        //具体时间计算，单位毫秒
        //闹钟的意图
        Log.v("hehe","alarm");
        if(flag){
            manager.setExact(AlarmManager.ELAPSED_REALTIME_WAKEUP, SystemClock.elapsedRealtime()+time*1000,pd);
        }else{
            manager.cancel(pd);
            stopSelf();
        }
        return super.onStartCommand(intent, flags, startId);
    }

    class AlarmBinder extends Binder {
        void setTime(int t){
            time=t;
            flag=true;
        }

        void setState(){
            flag=false;
        }

    }
}

AlarmService.java

package com.example.wkp.clock;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.util.Log;

/**
 * Created by wkp on 2016/9/24.
 */
public class AlarmReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        Log.v("hehe","receiver");
        context.startService(new Intent(context,AlarmService.class));
    }
}

AlarmReceiver.java

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.example.wkp.clock.MainActivity">

    <EditText
        android:id="@+id/edit"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"/>

    <Button android:id="@+id/start"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="启动"/>

    <Button android:id="@+id/stop"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="关闭"/>
</LinearLayout>

activity_main.xml

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原文地址：https://www.cnblogs.com/wangkaipeng/p/5904295.html