Caused by: java.lang.IllegalArgumentException: Service Intent must be explicit: Intent { act=m4 (has extras) }
                                                                              at android.app.ContextImpl.validateServiceIntent(ContextImpl.java:1809)
                                                                              at android.app.ContextImpl.startServiceCommon(ContextImpl.java:1838)
                                                                              at android.app.ContextImpl.startService(ContextImpl.java:1822)
                                                                              at android.content.ContextWrapper.startService(ContextWrapper.java:516)
                                                                              at myapplication.com.canvas.MainActivity.start(MainActivity.java:24)
                                                                              at java.lang.reflect.Method.invoke(Native Method) 
                                                                              at java.lang.reflect.Method.invoke(Method.java:372) 
                                                                              at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:284) 
                                                                              at android.view.View.performClick(View.java:4793) 
                                                                              at android.view.View$PerformClick.run(View.java:19960) 
                                                                              at android.os.Handler.handleCallback(Handler.java:739) 
                                                                              at android.os.Handler.dispatchMessage(Handler.java:95) 
                                                                              at android.os.Looper.loop(Looper.java:135) 
                                                                              at android.app.ActivityThread.main(ActivityThread.java:5593) 
                                                                              at java.lang.reflect.Method.invoke(Native Method) 
                                                                              at java.lang.reflect.Method.invoke(Method.java:372) 
                                                                              at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:967) 
                                                                              at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:762)
                                                                  

  <service android:name=".service.FirstService" >

            <intent-filter>

                <action android:name="m4" />

            </intent-filter>

  </service>

public class FirstService extends Service {

    /*

     * intent:startServcie(it)传入的值

     * startId:启动服务的次数序号

     *

     */

    @Override

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

        int x = intent.getIntExtra("x", 0);

        //System.out.println("--"+startId+"--"+x);

        if (x==88) {

            //停止服务

            stopSelf();

        }

        return super.onStartCommand(intent, flags, startId);

    }

     @Override

    public void onDestroy() {

        // TODO Auto-generated method stub

        super.onDestroy();

        System.out.println("--onDestroy");

    }

    @Override

    public IBinder onBind(Intent arg0) {

        // TODO Auto-generated method stub

        return null;

    }

}

public class MainActivity extends AppCompatActivity {

    TextView tv;

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

    }

    public void start(View v){

        Intent it=new Intent();

        it.setAction("m4");

        it.putExtra("x", 88);

        startService(it);

    }

}

 public void start(View v){

        Intent it=new Intent();

        it.setAction("m4");

        it.putExtra("x", 88);

        it.setPackage("myapplication.com.canvas");//应用的包名

        startService(it);

    }