無法啓動一個活動

Question

服務即時通訊工作在我的Android應用程序，我有一個奇怪的問題。 即時通訊嘗試從主要活動運行服務，但沒有運氣。無論我嘗試什麼，都不會出現日誌消息。我發現，當清除服務聲明時，我得到了「未找到」消息，但是當它返回時 - 日誌記錄是空的艱難，我嘗試打印。

我必須說，我`v試圖尋找答案數週，並閱讀一些解決方案的一些類似的問題，但再次沒有運氣就此事。

在活動

我這樣做：

startService(new Intent(this,GpsCompassService.class));

，並在服務中我做的：

`

public class GpsCompassService extends ManagerService{ 

    private static final String TAG = "GpsCompassServiceActivity"; 

    public void onCreate(Bundle savedInstanceState) { 
     Log.i("GpsCompassService onCreate", null);  
    } 
    //------------------------------------------------------------ 
    public void onResume(){ 
     Log.i("GpsCompassService has launched", null);; 
}` 

的manifst.xml： `

<?xml version="1.0" encoding="utf-8"?> 
<manifest xmlns:android="http://schemas.android.com/apk/res/android" 
    package="project.main.app" 
    android:versionCode="1" 
    android:versionName="1.0" > 

    <uses-sdk android:minSdkVersion="10" /> 
    <uses-permission android:name="android.permission.INTERNET"/> 
    <uses-permission android:name="android.permission.CAMERA" /> 
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" /> 

    <application android:name=".ManagerApplication" android:icon="@drawable/icon" android:label="@string/app_name" > 
     <activity android:label="@string/app_name" android:name=".MenuActivity" > 
      <intent-filter > 
       <action android:name="android.intent.action.MAIN" /> 
       <category android:name="android.intent.category.LAUNCHER" /> 
      </intent-filter> 
     </activity> 
     <activity android:label="@string/app_name" android:name="project.main.app.CameraPreviewActivity" > 
      <intent-filter > 
       <action android:name="android.intent.action.MAIN" /> 
       <category android:name="android.intent.category.DEFAULT" /> 
      </intent-filter> 
     </activity> 
     <service android:enabled="true" android:name="project.main.app.GpsCompassService"> 
      <intent-filter> 
       <action android:name="project.main.app.GpsCompassService"></action> 
      </intent-filter> 
     </service> 
    </application> 

</manifest> 

`

我在做什麼錯？

提前10倍！

package project.main.app; 

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

public class ManagerService extends Service { 

    public ManagerApplication getManagerApp(){ 
     ManagerApplication appSharedDate = (ManagerApplication)getApplication(); 
     return appSharedDate; 
    } 

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

} 

這裏是logcat的文件：

01-07 20:19:29.281: E/AndroidRuntime(557): FATAL EXCEPTION: main 
01-07 20:19:29.281: E/AndroidRuntime(557): java.lang.RuntimeException: Unable to create service project.main.app.GpsCompassService: java.lang.NullPointerException: println needs a message 
01-07 20:19:29.281: E/AndroidRuntime(557): at android.app.ActivityThread.handleCreateService(ActivityThread.java:1955) 
01-07 20:19:29.281: E/AndroidRuntime(557): at android.app.ActivityThread.access$2500(ActivityThread.java:117) 
01-07 20:19:29.281: E/AndroidRuntime(557): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:985) 
01-07 20:19:29.281: E/AndroidRuntime(557): at android.os.Handler.dispatchMessage(Handler.java:99) 
01-07 20:19:29.281: E/AndroidRuntime(557): at android.os.Looper.loop(Looper.java:130) 
01-07 20:19:29.281: E/AndroidRuntime(557): at android.app.ActivityThread.main(ActivityThread.java:3683) 
01-07 20:19:29.281: E/AndroidRuntime(557): at java.lang.reflect.Method.invokeNative(Native Method) 
01-07 20:19:29.281: E/AndroidRuntime(557): at java.lang.reflect.Method.invoke(Method.java:507) 
01-07 20:19:29.281: E/AndroidRuntime(557): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839) 
01-07 20:19:29.281: E/AndroidRuntime(557): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597) 
01-07 20:19:29.281: E/AndroidRuntime(557): at dalvik.system.NativeStart.main(Native Method) 
01-07 20:19:29.281: E/AndroidRuntime(557): Caused by: java.lang.NullPointerException: println needs a message 
01-07 20:19:29.281: E/AndroidRuntime(557): at android.util.Log.println_native(Native Method) 
01-07 20:19:29.281: E/AndroidRuntime(557): at android.util.Log.i(Log.java:158) 
01-07 20:19:29.281: E/AndroidRuntime(557): at project.main.app.GpsCompassService.onCreate(GpsCompassService.java:32) 
01-07 20:19:29.281: E/AndroidRuntime(557): at android.app.ActivityThread.handleCreateService(ActivityThread.java:1945) 

Answer 1

和MisterSquonk一樣，刪除您的onResume()方法並更改您的onCreate()方法。

然後換行

public class GpsCompassService extends ManagerService{ 

到

public class GpsCompassService extends Service{ 

您ManagerService聲明的內容可以很容易地實現到服務的onCreate()方法或到像

@Override 
public int onStartCommand(Intent intent, int flags, int startId) { 
    super.onStart(intent, startId); 
    doSomething(); 
    return START_NOT_STICKY; // or START_STICKY, depending on your needs 
} 

的方法還要更改行

Log.i("GpsCompassService onCreate", null);  

到

Log.i("GpsCompassService onCreate", "some message");  

否則該應用程序會崩潰，作爲第二個參數不能爲null。

Answer 2

假設ManagerService延伸Service則既不以下方法是有效的一個Service，絕不會被稱爲......

public void onCreate(Bundle savedInstanceState) { 
    Log.i("GpsCompassService onCreate", null);  
} 
//------------------------------------------------------------ 
public void onResume(){ 
    Log.i("GpsCompassService has launched", null);; 

Service的onCreate()方法不採用任何參數，而onResume()根本不是Service方法。

刪除onResume()和改變你的onCreate()代碼類似...

@Override 
public void onCreate() { 
    Log.i("GpsCompassService", "onCreate()");  
} 

編輯：此外，使用Log當不使用null第二（消息）參數。