android - java.lang.InstantiationException 安卓

Question

你好，我有一个问题，但没有找到解决方法我的逻辑是

05-23 09:44:20.164  10374-10374/? E/AndroidRuntime﹕ FATAL EXCEPTION: main
    java.lang.RuntimeException: Unable to instantiate service ramazan.com.dovizfiyarlari.tab1$LocalService: java.lang.InstantiationException: can't instantiate class ramazan.com.dovizfiyarlari.tab1$LocalService; no empty constructor
            at android.app.ActivityThread.handleCreateService(ActivityThread.java:2347)
            at android.app.ActivityThread.access$1600(ActivityThread.java:130)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1277)
            at android.os.Handler.dispatchMessage(Handler.java:99)
            at android.os.Looper.loop(Looper.java:137)
            at android.app.ActivityThread.main(ActivityThread.java:4745)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:511)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
            at dalvik.system.NativeStart.main(Native Method)
     Caused by: java.lang.InstantiationException: can't instantiate class ramazan.com.dovizfiyarlari.tab1$LocalService; no empty constructor
            at java.lang.Class.newInstanceImpl(Native Method)
            at java.lang.Class.newInstance(Class.java:1319)
            at android.app.ActivityThread.handleCreateService(ActivityThread.java:2344)
            at android.app.ActivityThread.access$1600(ActivityThread.java:130)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1277)
            at android.os.Handler.dispatchMessage(Handler.java:99)
            at android.os.Looper.loop(Looper.java:137)
            at android.app.ActivityThread.main(ActivityThread.java:4745)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:511)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
            at dalvik.system.NativeStart.main(Native Method)

和服务代码

public class LocalService extends IntentService
    {
        public LocalService () {
            super("MyServerOrWhatever");
        }
        private  Timer timer = new Timer();
        private Context ctx;

        public IBinder onBind(Intent arg0)
        {
            return null;
        }

        @Override
        protected void onHandleIntent(Intent intent) {
            Dolar dolar = new Dolar();
            dolar.execute();
        }

        public void onCreate()
        {
            super.onCreate();
            ctx = this;
            startService();
        }

        private void startService()
        {
            timer.scheduleAtFixedRate(new mainTask(), 0, 5000);
        }

        private class mainTask extends TimerTask
        {
            public void run()
            {
                toastHandler.sendEmptyMessage(0);
            }
        }

        public void onDestroy()
        {
            super.onDestroy();
            Toast.makeText(this, "Service Stopped ...", Toast.LENGTH_SHORT).show();
        }

        private final Handler toastHandler = new Handler()
        {
            @Override
            public void handleMessage(Message msg)
            {
                Dolar dolar=new Dolar();
                dolar.execute();

            }
        };
    }
    
    and 

worker 代码是

if(isNetworkAvailable(tab1.this)==true) {
          LocalService localService=new LocalService();
           startService(new Intent(tab1.this,LocalService.class));
  
  
  ]
  
    public class Dolar extends AsyncTask<String,String,String>{
    ProgressDialog pd;
    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        pd=new ProgressDialog(tab1.this);
        pd.setMessage("yukleniyor");
        pd.show();
    }

    @Override
    protected void onPostExecute(String s) {
        super.onPostExecute(s);
        txt_dolar.setText(kur);
        txt_altin_gram.setText(altin);
        txt_ceyrek.setText(ceyrek);
        pd.dismiss();
    }
String altin="";
    String  ceyrek;
    @Override
    protected String doInBackground(String... params) {
        Document document = null;

        try {
            document = Jsoup.connect("http://www.reuters.com/finance/currencies/quote?srcAmt=1.00&srcCurr=USD&destAmt=&destCurr=TRY")
                    .userAgent("Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_1) AppleWebKit/600.1.25 (KHTML, like Gecko) " +
                            "Version/8.0 Safari/600.1.25").get();
        } catch (IOException e) {
            e.printStackTrace();
        }
        int sayac = 0;
        Elements sondakika = document.select("div.norm");
        for (Element element : sondakika) {
             if(sayac==0){
                 kur=element.text();
             }
            sayac=sayac+1;
        }
      
      }

你能帮帮我吗...

Answer 1

删除这一行，它没有用，也是你问题的原因。您不能在 Android 中手动实例化服务/Activity ，它禁止它，因此您的异常(exception)。

 LocalService localService = new LocalService();