无法绑定到服务

Question

虽然我遵循Android Developers网站上的教程，但无法将我的活动绑定到我的服务。

package com.dieselboris.motioncapture; 

import android.app.Activity; 
import android.app.AlertDialog; 
import android.content.ComponentName; 
import android.content.Context; 
import android.content.Intent; 
import android.content.ServiceConnection; 
import android.os.Bundle; 
import android.os.IBinder; 
import android.view.View; 
import android.view.View.OnClickListener; 
import android.widget.Button; 
import android.widget.EditText; 
import android.widget.TextView; 
import android.widget.Toast; 

import com.dieselboris.motioncapture.LocalService.LocalBinder; 

public class HelloMotionCaptureActivity extends Activity implements OnClickListener { 
    private TextView textBox; 
    LocalService mService; 
    boolean mBound = false; 


    /** Called when the activity is first created. */ 
    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.main); 
     textBox = (TextView) findViewById(R.id.textView1); 
    } 

    @Override 
    protected void onStart() { 
     super.onStart(); 
     // Bind to LocalService NEVER RETURNS TRUE!!!! 
     Intent intent = new Intent(this, LocalService.class); 
     boolean isBound = bindService(intent, mConnection, Context.BIND_AUTO_CREATE); 
     String text = Boolean.toString(isBound); 
     textBox.setText(text); 

    } 

    @Override 
    protected void onStop() { 
     super.onStop(); 
     // Unbind from the service 
     if (mBound) { 
      unbindService(mConnection); 
      mBound = false; 
     } 
    } 

    //start the service when clicked 
    public void onClick(View v) { 

     if (v == startButton) 
     { 
      //NEVER IN HERE 
      if (mBound) { 
       int num = mService.getRandomNumber(); 
       Toast.makeText(this, "incoming number: " + num, Toast.LENGTH_LONG).show(); 
      } 
      Toast.makeText(this, "the service should run now", Toast.LENGTH_LONG).show(); 

     } 
    } 

    /** Defines callbacks for service binding, passed to bindService() */ 
    private ServiceConnection mConnection = new ServiceConnection() { 

     @Override 
     public void onServiceConnected(ComponentName className, 
       IBinder service) { 
      // We've bound to LocalService, cast the IBinder and get LocalService instance 
      LocalBinder binder = (LocalBinder) service; 
      mService = binder.getService(); 
      mBound = true; 
      if (mBound) { 
       // Call a method from the LocalService. 
       // However, if this call were something that might hang, then this request should 
       // occur in a separate thread to avoid slowing down the activity performance. 
       int num = mService.getRandomNumber(); 
       String text = Integer.toString(num); 
       textBox.setText(text); 
      } 
     } 

     @Override 
     public void onServiceDisconnected(ComponentName arg0) { 
      mBound = false; 
     } 
    }; 
} 

我尝试连接到服务：

package com.dieselboris.motioncapture; 

import java.util.Random; 

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

public class LocalService extends Service { 
    // Binder given to clients 
    private final IBinder mBinder = new LocalBinder(); 
    // Random number generator 
    private final Random mGenerator = new Random(); 

    /** 
    * Class used for the client Binder. Because we know this service always 
    * runs in the same process as its clients, we don't need to deal with IPC. 
    */ 
    public class LocalBinder extends Binder { 
     LocalService getService() { 
      // Return this instance of LocalService so clients can call public methods 
      return LocalService.this; 
     } 
    } 

    @Override 
    public IBinder onBind(Intent intent) { 
     return mBinder; 
    } 

    /** method for clients */ 
    public int getRandomNumber() { 
     return mGenerator.nextInt(100); 
    } 
} 

我从仿真器输出如下：

ERROR/AndroidRuntime（10878）：致命异常：主要
ERROR/AndroidRuntime（10878）：java.lang.NullPointerException
ERROR/AndroidRuntime（10878）：at com.dieselboris.motioncapture.HelloMotionCaptur eActivity.onClick（HelloMotionCaptureActivity.java:66）
ERROR/AndroidRuntime（10878）：at android.view.View.performClick（View.java:2408）
ERROR/AndroidRuntime（10878）：at android.view.View $ PerformClick.run（View.java:8817）
ERROR/AndroidRuntime（10878）：在android.os.Handler.handleCallback（Handler.java:587）
ERROR/AndroidRuntime（10878）：在android.os.Handler。 dispatchMessage（Handler.java:92）
ERROR/AndroidRuntime（10878）：at android.os.Looper.loop（Looper.java:144）
ERROR/AndroidRuntime（10878）：at android.app.ActivityThread.main（ ActivityThread.java:4937）
错误/ AndroidRuntime（ 10878）：at java.lang.reflect.Method.invokeNative（Native Method）
ERROR/AndroidRuntime（10878）：at java.lang.reflect.Method.invoke（Method.java:521）
ERROR/AndroidRuntime（10878） ）：at com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run（ZygoteInit.java:868）
ERROR/AndroidRuntime（10878）：at com.android.internal.os.ZygoteInit.main（ZygoteInit.java:626 ）
ERROR/AndroidRuntime（10878）：在dalvik.system.NativeStart.main（本机方法）

看来，我称之为从服务公众方法之前，它的初始化或连接尚未建立。

我仔细地在开发者网站上跟踪了这个例子，并且无法弄清楚我做错了什么。

Answer 1

我的权限werent设置正确。

我不得不为整个应用程序插入一个权限，并在应用程序清单中插入一个“uses-permission”。

没有权限，意图永远不会传递到服务。