android-service的简单用法

service是android开发中的四大组件之一,下面来介绍service的简单用法

1.需要新建一个service类,该类继承与service接口,需要实现onBind方法,这个方法之后介绍

2.创建intent对象,设置intent的目标为新建的service的类,启动service的方法有两种用startservice方法和bindservice方法

　　两种方法的不同在于startservice在启动服务之后,关闭当前的activity之后service还在系统后台运行

　　bindservice启动服务后将服务与主界面绑定,主界面关闭之后service也就结束了

3.主界面与service的信息交互需要用到aidl,需要在项目src下新建aidl包,并新建接口,会自动在gen目录下生成对应的java文件,这些东西都是不用进行修改的.

另外,一定记得在androiManifest中注册service

package com.wentjiang.shixi_service;

import com.wentjiang.shixi_service.aidl.MyInterface;

import android.R.string;
import android.app.Activity;
import android.app.Service;
import android.content.BroadcastReceiver;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.ServiceConnection;
import android.os.Bundle;
import android.os.IBinder;
import android.os.RemoteException;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;

public class MainActivity extends Activity implements OnClickListener{
    private Button mStartService,mStopService,mBindService,mUnbindService,mAidl;
    private TextView mTextView;
    private ServiceConnection mConn;
    private MyReceiver myreceiver;
    private MyInterface mInterface;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        initData();
        initView();
    }

    private void initView() {
        mStartService=(Button) findViewById(R.id.startService);
        mStopService=(Button) findViewById(R.id.stopService);
        mBindService=(Button) findViewById(R.id.bindService);
        mUnbindService=(Button) findViewById(R.id.unbindService);
        mAidl=(Button) findViewById(R.id.aidl);
        mTextView=(TextView) findViewById(R.id.text);
        mStartService.setOnClickListener(this);
        mStopService.setOnClickListener(this);
        mBindService.setOnClickListener(this);
        mUnbindService.setOnClickListener(this);
        mAidl.setOnClickListener(this);

    }

    private void initData() {
        mConn=new ServiceConnection() {

            @Override
            public void onServiceDisconnected(ComponentName name) {
                //连接失败时调用的方法

            }

            @Override
            public void onServiceConnected(ComponentName name, IBinder service) {
                //连接成功是调用的方法
                Log.i("连接成功了", "---");
                mInterface=MyInterface.Stub.asInterface(service);
            }
        };
        myreceiver=new MyReceiver();
        IntentFilter filter = new IntentFilter();
        filter.addAction("action.went");

        registerReceiver(myreceiver, filter);

    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }

    @Override
    public void onClick(View v) {
        Intent intent =new Intent(this, MyService.class);
        switch (v.getId()) {
        case R.id.startService:
            startService(intent);
            break;
        case R.id.stopService:
            stopService(intent);
            break;
        case R.id.bindService:
            bindService(intent, mConn, Service.BIND_AUTO_CREATE);
            break;
        case R.id.unbindService:
            unbindService(mConn);
            break;
        case R.id.aidl:
            try {
                int num= mInterface.getmul(10, 6);
                mTextView.setText(String.valueOf(num));
            } catch (RemoteException e) {
                e.printStackTrace();
            }
        default:
            break;
        }
    }

    public class MyReceiver extends BroadcastReceiver{

        @Override
        public void onReceive(Context context, Intent intent) {
            String action = intent.getAction();
            if("action.went".equals(action)){
                int num=intent.getIntExtra("num", 0);
                mTextView.setText(String.valueOf(num));
            }
        }

    }
}

MainActivity

package com.wentjiang.shixi_service;

import java.util.Timer;
import java.util.TimerTask;

import com.wentjiang.shixi_service.MainActivity.MyReceiver;
import com.wentjiang.shixi_service.aidl.MyInterface;

import android.R.integer;
import android.app.Service;
import android.content.Intent;
import android.content.IntentFilter;
import android.net.ConnectivityManager;
import android.os.IBinder;
import android.os.RemoteException;
import android.util.Log;

public class MyService extends Service {
    private MyReceiver mReceiver;
    private MyInterface.Stub mBinder = new MyInterface.Stub() {

        @Override
        public int getmul(int num1, int num2) throws RemoteException {
            int temp=num1*num2;
            return temp;
        }
    };

    @Override
    public IBinder onBind(Intent intent) {
        Log.i("onbind被调用了", "----");
        return mBinder;
    }

    @Override
    public void onCreate() {
        super.onCreate();
        Log.i("oncreate被调用了", "----");
    }

    @Override
    public void onDestroy() {
        Log.i("onDestroy被调用了", "---");
        super.onDestroy();
    }

    @Override
    public void onRebind(Intent intent) {
        Log.i("onRebind", "---");
        super.onRebind(intent);
    }

}

MyService

package com.wang.service.aidl;

interface MyInterface{

    int mul(int a, int b);

}

MyInterface

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#ffffff"
    android:orientation="vertical"
    android:padding="20dp" >

    <TextView
        android:id="@+id/tv"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Test"
        android:textColor="#000000"
        android:textSize="24sp" />

    <Button
        android:id="@+id/btn01"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Start Service" />

    <Button
        android:id="@+id/btn02"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Stop Service" />

    <Button
        android:id="@+id/btn03"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="bind Service" />

    <Button
        android:id="@+id/btn04"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="unbind Service" />

    <Button
        android:id="@+id/btn05"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:text="work" />

</LinearLayout>

activity_main