Android课程---关于Service的学习(后台运行)

MainActivity.java

package com.hanqi.test2;

import android.content.ComponentName;
import android.content.Context;
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.Toast;

public class MainActivity extends AppCompatActivity {

    protected void onCreate(Bundle savedInstanceState)
     {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }
    //一般方式启动Service
    //参考Activity 的启动方式
    public void bt1_onclick(View v)
    {
        //通过意图Intent
        //显式意图
        Intent intent = new Intent(this,TestService1.class);

        startService(intent);

        Toast.makeText(MainActivity.this, "启动Service", Toast.LENGTH_SHORT).show();

    }
    public void bt2_onclick(View v)
    {
        //通过意图Intent
        //显式意图
        Intent intent = new Intent(this,TestService1.class);

        stopService(intent);

        Toast.makeText(MainActivity.this, "停止Service", Toast.LENGTH_SHORT).show();

    }
    ServiceConnection sc;
    public void bt3_onclick(View v)
    {
        //通过意图Intent
        //显式意图
        Intent intent = new Intent(this,TestService1.class);
        if (sc == null) {

            sc = new ServiceConnection() {
                @Override
                public void onServiceConnected(ComponentName name, IBinder service) {

                    Log.e("TAG", "连接服务");
                }

                @Override
                public void onServiceDisconnected(ComponentName name) {

                    Log.e("TAG", "断开连接服务");
                }
            };
        }
        //参数：意图，连接，绑定方式 BIND_AUTO_CREATE:自动创建
        bindService(intent,sc, Context.BIND_AUTO_CREATE);

        Toast.makeText(MainActivity.this, "绑定服务成功", Toast.LENGTH_SHORT).show();

    }

    public void bt4_onclick(View v)
    {
        //判断是否已经绑定，连接是否为空
        if (sc != null)
        {
            //解除绑定
            unbindService(sc);
            sc = null;
            Toast.makeText(MainActivity.this, "解除绑定", Toast.LENGTH_SHORT).show();
        }
        else
        {
            Toast.makeText(MainActivity.this, "尚未绑定", Toast.LENGTH_SHORT).show();
        }
    }

    @Override
    protected void onDestroy() {


        if (sc != null) {
            //解除绑定
            unbindService(sc);
            sc = null;
        }
        super.onDestroy();
    }
}

TestService1.java

package com.hanqi.test2;

import android.app.Service;
import android.content.Intent;
import android.os.Binder;
import android.os.IBinder;
import android.util.Log;

public class TestService1 extends Service {
    public TestService1() {

        Log.e("TAG","构造Service");
    }

    //绑定的回调方法
    //必须要重写
    @Override
    public IBinder onBind(Intent intent) {
        // TODO: Return the communication channel to the service.
        //throw new UnsupportedOperationException("Not yet implemented");

        Log.e("TAG","绑定被调用");
        return new Binder();
    }

    @Override
    public void onCreate() {

        Log.e("TAG","创建Service");
        super.onCreate();
    }

    @Override
    public void onDestroy() {

        Log.e("TAG","销毁Service");
        super.onDestroy();
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {

        Log.e("TAG","启动命令");
        return super.onStartCommand(intent, flags, startId);
    }

    @Override
    public boolean onUnbind(Intent intent) {

        Log.e("TAG","解除绑定");
        return super.onUnbind(intent);
    }
}

activity_main.xml

<?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: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.hanqi.test2.MainActivity"
    android:orientation="vertical">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
        <Button
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="一般启动服务"
            android:onClick="bt1_onclick"/>
        <Button
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="一般停止服务"
            android:onClick="bt2_onclick"/>
    </LinearLayout>
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
        <Button
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="绑定启动服务"
            android:onClick="bt3_onclick"/>
        <Button
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="解绑停止服务"
            android:onClick="bt4_onclick"/>
    </LinearLayout>
</LinearLayout>

效果图：