旺仔练习：service的普通方式和绑定方式的启动和停止（解绑出现异常，尚未解决）

package com.hanqi.dianhuabohaoqi;

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.view.View;
import android.widget.Button;
import android.widget.Toast;

public class usingservice extends AppCompatActivity {
Button bt_1,bt_2,bt_3,bt_4;
Intent intentservice;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_usingservice);
bt_1=(Button)findViewById(R.id.bt_1);
bt_2=(Button)findViewById(R.id.bt_2);
bt_3=(Button)findViewById(R.id.bt_3);
bt_4=(Button)findViewById(R.id.bt_4);
bt_1.setOnClickListener(new start_service());
bt_2.setOnClickListener(new start_service());
bt_3.setOnClickListener(new start_service());
bt_4.setOnClickListener(new start_service());
intentservice=new Intent(this,EchoService.class);

}
class start_service implements View.OnClickListener
{
ServiceConnection sc;
public void onClick(View v)
{
if (sc==null){
sc= new ServiceConnection() {
@Override
public void onServiceConnected(ComponentName name, IBinder service) {
//接收代理对象进行强转
EchoService.MyBind echo=(EchoService.MyBind)service;

Toast.makeText(usingservice.this, "绑定service成功连接，接收返回对象="+echo.gettest(), Toast.LENGTH_SHORT).show();
}

@Override
public void onServiceDisconnected(ComponentName name) {

}
};
}

switch (v.getId())
{
case R.id.bt_1://启动service
startService(intentservice);
break;
case R.id.bt_2://停止service
stopService(intentservice);
break;
case R.id.bt_3://绑定方式启动service
bindService(intentservice,sc , Context.BIND_AUTO_CREATE);
break;
case R.id.bt_4://解除绑定
if (sc!=null){
unbindService(sc);
sc=null;
}else
{
Toast.makeText(usingservice.this, "清先绑定服务", Toast.LENGTH_SHORT).show();
}
break;
}
}
}
}

package com.hanqi.dianhuabohaoqi;

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

public class EchoService extends Service {
public EchoService() {
Log.e("TAG","service被构造");
}

@Override
public void onCreate() {
Log.e("TAG","启动service");
super.onCreate();
}

@Override
public void onDestroy() {
Log.e("TAG","停止service");
super.onDestroy();
}

@Override
public int onStartCommand(Intent intent, int flags, int startId) {
Log.e("TAG","onStartCommand被调用");
return super.onStartCommand(intent, flags, startId);
}
@Override
public boolean onUnbind(Intent intent) {
Log.e("TAG","onUnbind被调用");
return super.onUnbind(intent);
}
//内部类
public class MyBind extends Binder
{
//定义数据交互的方法
public int gettest()
{
return 123;
}
};

@Override
public IBinder onBind(Intent intent) {
Log.e("TAG","onBind被调用");
// throw new UnsupportedOperationException("Not yet implemented");
return new MyBind();

}
}

<?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:orientation="vertical"
tools:context="com.hanqi.dianhuabohaoqi.usingservice">
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/bt_1"
android:text="启动service"/>
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/bt_2"
android:text="停止service"/>
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/bt_3"
android:text="绑定service"/>
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/bt_4"
android:text="解除绑定service"/>

</LinearLayout>