не может запустить службу андроида из активности, которая находится в другом пакете

Question

Я новичок в стеке android. Я пытаюсь запустить службу Android от launcher activity. Service и Activity определены в отдельных пакетах, но они не запускаются. В logcat нет никаких исключений или ошибок. Я проверил много вопросов по stackoverflow по этой проблеме, но это не сработало. Ниже приведен исходный код моего приложения. Я потратил почти 8 часов на эту проблему. Любая помощь будет большой оценкой.

AndroidManifest.xml: 
<?xml version="1.0" encoding="utf-8"?> 
<manifest xmlns:android="http://schemas.android.com/apk/res/android" 
    package="nl.test.app"> 

    <supports-screens 
     android:anyDensity="true" 
     android:largeScreens="true" 
     android:normalScreens="true" 
     android:resizeable="true" 
     android:smallScreens="true" 
     android:xlargeScreens="true" /> 

    <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" /> 
    <uses-permission android:name="android.permission.READ_PHONE_STATE" /> 
    <uses-permission android:name="android.permission.INTERNET" /> 
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /> 
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" /> 

    <application 
     android:allowBackup="true" 
     android:icon="@drawable/ic_launcher" 
     android:label="@string/app_name" 
     android:supportsRtl="true" 
     android:theme="@style/AppTheme">   
     <activity 
      android:name=".ui.LoginActivity" 
      android:label="@string/app_name" 
      android:theme="@style/AppTheme"> 
      <intent-filter> 
       <action android:name="android.intent.action.MAIN" /> 

       <category android:name="android.intent.category.LAUNCHER" /> 
      </intent-filter> 
     </activity>  
     <service 
      android:name=".messaging.AlertService" 
      android:enabled="true" 
      android:exported="true"> 
     </service> 
    </application> 
</manifest> 

AlertService.java:

package nl.test.app.messaging; 

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

public class AlertService extends Service { 

    public AlertService() { 
    } 

    @Override 
    public IBinder onBind(Intent intent) { 
     // TODO: Return the communication channel to the service. 
     throw new UnsupportedOperationException("Not yet implemented"); 
    } 
    @Override 
    public void onCreate() { 
     super.onCreate(); 
     Toast.makeText(getApplicationContext(), "on create called\n", Toast.LENGTH_LONG).show(); 

    } 
    @Override 
    public int onStartCommand(Intent intent, int flags, int startId) { 
     return START_STICKY; 
    } 
} 

LoginActivity.java

package nl.test.app.ui; 

import android.content.ComponentName; 
import android.content.Intent; 
import android.os.Bundle; 
import android.support.v7.app.AppCompatActivity; 
import android.util.Log; 
import android.view.View; 
import android.view.WindowManager; 
import android.widget.EditText; 
import android.widget.Toast; 

import nl.test.app.R; 

public class LoginActivity extends AppCompatActivity{ 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_login); 

    } 

    // function for service testing 
    public void onStartButtonClick(View view) { 
     Intent myIntentToStartAlertListActivity = new Intent(); 
     String pkg = "nl.test.app.messaging"; 
     String cls = "nl.test.app.messaging.AlertService"; 
     myIntentToStartAlertListActivity.setComponent(new ComponentName(pkg, cls)); 

    if (startService(myIntentToStartAlertListActivity) != null) { 
      Log.i("Service Started","Service started"); 
      Toast.makeText(getApplicationContext(), "Service is running\n", Toast.LENGTH_LONG).show(); 
     } 
     else { 
      Toast.makeText(getApplicationContext(), "Service is not running\n", Toast.LENGTH_LONG).show(); 
     } 
    } 

    @Override 
    protected void onStop() { 
     super.onStop(); 

    } 
} 

Answer 1

// function for service testing 
public void onStartButtonClick(View view) { 
    Intent myIntentToStartAlertListActivity = new Intent(LoginActivity.this,AlertService.class); 
    String pkg = "nl.test.app.messaging"; 
    String cls = "nl.test.app.messaging.AlertService"; 
    myIntentToStartAlertListActivity.setComponent(new ComponentName(pkg, cls)); 
    //startService(myIntentToStartAlertListActivity) 

if (startService(myIntentToStartAlertListActivity) != null) { 
     Log.i("Service Started","Service started"); 
     Toast.makeText(getApplicationContext(), "Service is running\n", Toast.LENGTH_LONG).show(); 
    } 
    else { 
     Toast.makeText(getApplicationContext(), "Service is not running\n", Toast.LENGTH_LONG).show(); 
    } 
} 

Answer 2

Попробуйте

public void onStartButtonClick(View view) { 
    Intent myIntentToStartAlertListActivity = new Intent(LoginActivity.this, AlertService.class); 
if (startService(myIntentToStartAlertListActivity) != null) { 
     Log.i("Service Started","Service started"); 
     Toast.makeText(getApplicationContext(), "Service is running\n", Toast.LENGTH_LONG).show(); 
    } 
    else { 
     Toast.makeText(getApplicationContext(), "Service is not running\n", Toast.LENGTH_LONG).show(); 
    } 
}