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java Android服务意外停止

对于我正在制作的安卓应用程序,我希望有一个服务,即使在应用程序没有运行的情况下,也能检查a数据库是否存在攻击(有点像facebook在关闭的情况下如何通知某些东西),因此我制作了下面的类,然而,在我停止运行我的应用程序一分钟后,我收到一条消息“应用程序已意外停止”,几分钟后再次出现。。。我知道可能会因为很多应用程序都在做检查而一直检查,但我做错了什么? 这就是我目前的情况:

    package com.ducknoise.toonfight;

import java.sql.SQLException;

import 安卓.app.NotificationManager;
import 安卓.app.Service;
import 安卓.content.Intent;
import 安卓.os.AsyncTask;
import 安卓.os.Build;
import 安卓.os.IBinder;
import 安卓.support.v4.app.NotificationCompat;
import 安卓.support.v4.app.NotificationCompat.Builder;
import 安卓.widget.Toast;

public class ToonService extends Service{
    public static ToonService toonService;
    public ToonService(){
        toonService = this;
    }
    @Override
    public IBinder onBind(Intent intent) {
        String toonName = intent.getStringExtra("toonName");
        ToonDB task = new ToonDB();
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
            task.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR,toonName);
        } else {
            task.execute(toonName);
        }
        return null;
    }
    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {

        String toonName = intent.getStringExtra("toonName");
        ToonDB task = new ToonDB();
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
            task.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR,toonName);
        } else {
            task.execute(toonName);
        }
        return Service.START_STICKY;
    }

    @Override
    public void onCreate() {
        super.onCreate();
    }

    @Override
    public void onDestroy() {
        Toast.makeText(getApplicationContext(), "Disconnected with Server", Toast.LENGTH_LONG).show();
        Database db = new Database();
        db.closeConnection();
        super.onDestroy();
    }

    public class ToonDB extends AsyncTask<String,Void, Void>{

        Toon toon;
        @Override
        protected Void doInBackground(String... params) {
            Database db = new Database();
            db.establishConnection();
            toon = db.getToonFromDB(params[0]);

            return null;

        }
        @Override
        protected void onPostExecute(Void result) {
            ToonCheck task = new ToonCheck();
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
                task.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR,toon);
            } else {
                task.execute(toon);
            }
            super.onPostExecute(result);
        }

    }
    public class ToonCheck extends AsyncTask<Toon,Void, Void>{

        boolean runCheck;
        Toon toon;
        @Override
        protected Void doInBackground(Toon... params) {
            runCheck = true;
            Database db = new Database();
            db.establishConnection();
            toon = params[0];
            toon.updateCheckDB();
            publishProgress();
            if(!db.isOnline(toon))
                runCheck = false;

            return null;

        }
        @Override
        protected void onProgressUpdate(Void... values) {
            Battle battle = toon.getBattle();
            if(battle != null ){
                if(battle.notified()){
                    NotificationCompat.Builder nBuilder = new NotificationCompat.Builder(getApplicationContext());
                    nBuilder.setContentTitle("Toon Fight");
                    String contentText = battle.getOppName() + " has attacked you!";
                    nBuilder.setContentText(contentText);
                    nBuilder.setSmallIcon(R.drawable.ic_launcher);
                    int notiID = 1295;
                    NotificationManager notificationManager = (NotificationManager)getSystemService(NOTIFICATION_SERVICE);
                    notificationManager.notify(notiID, nBuilder.build());
                }
            }
            super.onProgressUpdate(values);
        }
        @Override
        protected void onPostExecute(Void result) {
            if(runCheck){
                ToonCheck task = new ToonCheck();
                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
                    task.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR,toon);
                } else {
                    task.execute(toon);
                }
            }else 
                stopSelf();
            super.onPostExecute(result);
        }

    }
}

这是logcat

03-24 11:01:41.968: D/AndroidRuntime(4624): Shutting down VM
03-24 11:01:41.968: W/dalvikvm(4624): threadid=1: thread exiting with uncaught exception (group=0x41f5aac8)
03-24 11:01:41.968: E/AndroidRuntime(4624): FATAL EXCEPTION: main
03-24 11:01:41.968: E/AndroidRuntime(4624): java.lang.RuntimeException: Unable to start service com.ducknoise.toonfight.ToonService@430a3950 with null: java.lang.NullPointerException
03-24 11:01:41.968: E/AndroidRuntime(4624):     at 安卓.app.ActivityThread.handleServiceArgs(ActivityThread.java:2782)
03-24 11:01:41.968: E/AndroidRuntime(4624):     at 安卓.app.ActivityThread.access$2000(ActivityThread.java:152)
03-24 11:01:41.968: E/AndroidRuntime(4624):     at 安卓.app.ActivityThread$H.handleMessage(ActivityThread.java:1385)
03-24 11:01:41.968: E/AndroidRuntime(4624):     at 安卓.os.Handler.dispatchMessage(Handler.java:99)
03-24 11:01:41.968: E/AndroidRuntime(4624):     at 安卓.os.Looper.loop(Looper.java:137)
03-24 11:01:41.968: E/AndroidRuntime(4624):     at 安卓.app.ActivityThread.main(ActivityThread.java:5329)
03-24 11:01:41.968: E/AndroidRuntime(4624):     at java.lang.reflect.Method.invokeNative(Native Method)
03-24 11:01:41.968: E/AndroidRuntime(4624):     at java.lang.reflect.Method.invoke(Method.java:511)
03-24 11:01:41.968: E/AndroidRuntime(4624):     at com.安卓.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1102)
03-24 11:01:41.968: E/AndroidRuntime(4624):     at com.安卓.internal.os.ZygoteInit.main(ZygoteInit.java:869)
03-24 11:01:41.968: E/AndroidRuntime(4624):     at dalvik.system.NativeStart.main(Native Method)
03-24 11:01:41.968: E/AndroidRuntime(4624): Caused by: java.lang.NullPointerException
03-24 11:01:41.968: E/AndroidRuntime(4624):     at com.ducknoise.toonfight.ToonService.onStartCommand(ToonService.java:34)
03-24 11:01:41.968: E/AndroidRuntime(4624):     at 安卓.app.ActivityThread.handleServiceArgs(ActivityThread.java:2765)
03-24 11:01:41.968: E/AndroidRuntime(4624):     ... 10 more

我是这样称呼这项服务的:

Intent toonService = new Intent(MainActivity.this, ToonService.class);
                toonService.putExtra("toonName", toon.getName());
                MainActivity.this.startService(toonService);

共 (1) 个答案

  1. # 1 楼答案

    你应该检查你的intentonStartCommandnull还是不是根据你的logcat

    03-24 11:01:41.968: E/AndroidRuntime(4624): Caused by: java.lang.NullPointerException
    03-24 11:01:41.968: E/AndroidRuntime(4624): at
    com.ducknoise.toonfight.ToonService.onStartCommand(ToonService.java:34)
    

    请展示一下如何开始Service