Ошибка приложения для Android «К сожалению приложение остановлено»

Question

Я изучаю разработку Android, и я слежу за учебником по youtube, и я пытаюсь запустить этот код, и я продолжаю получать «К сожалению приложение остановлено», похоже, что проблема когда я запускаю Activity «startActivity (menuIntent)»; это MainActivity.java:

package com.example.thebasicseries; 
import android.media.MediaPlayer; 
import android.os.Bundle; 
import android.app.Activity; 
import android.content.Intent; 


public class MainActivity extends Activity { 

MediaPlayer logoMusic; 

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

    logoMusic = MediaPlayer.create(MainActivity.this, R.raw.sound); 
    logoMusic.start(); 

    Thread logoTimer = new Thread(){ 
     public void run(){ 
      try { 
       sleep(5000); 
       Intent menuIntent = new Intent("com.example.thebasicseries.menu"); 
       startActivity(menuIntent); 
      } catch (InterruptedException e) { 
       // TODO Auto-generated catch block 
       e.printStackTrace(); 
      } finally{ 
       finish(); 
      } 
     } 
    }; 
    logoTimer.start(); 
} 

@Override 
protected void onPause() { 
    // TODO Auto-generated method stub 
    super.onPause(); 
    logoMusic.release(); 
} 


} 

И это menu.java

package com.example.thebasicseries; 
import android.app.Activity; 
import android.content.Intent; 
import android.media.MediaPlayer; 
import android.os.Bundle; 
import android.view.View; 
import android.widget.Button; 

public class menu extends Activity { 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    // TODO Auto-generated method stub 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 

    //Button sound 
    final MediaPlayer buttonSound = MediaPlayer.create(menu.this, R.raw.button); 

    //Setting up the button references 
    Button tut1 = (Button) findViewById(R.id.tutorial1); 
    Button tut2 = (Button) findViewById(R.id.tutorial2); 

    tut1.setOnClickListener(new View.OnClickListener() { 

     @Override 
     public void onClick(View v) { 
      // TODO Auto-generated method stub 
      buttonSound.start(); 
      startActivity(new Intent("com.example.thebasicseries.TutorialOne")); 
     } 
    });  


    tut2.setOnClickListener(new View.OnClickListener() { 

     @Override 
     public void onClick(View v) { 
      // TODO Auto-generated method stub 
      buttonSound.start(); 
      startActivity(new Intent("com.example.thebasicseries.TutorialOne")); 
     } 
    });  




} 

@Override 
protected void onPause() { 
    // TODO Auto-generated method stub 
    super.onPause(); 
} 

    } 

Это проявляется:

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

<uses-sdk 
    android:minSdkVersion="8" 
    android:targetSdkVersion="17" /> 

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

      <category android:name="android.intent.category.LAUNCHER" /> 
     </intent-filter> 
    </activity> 
    <activity 
     android:name="com.example.thebasicseries.menu" 
     android:label="@string/app_name" > 
     <intent-filter> 
      <action android:name="com.example.thebasicseries.menu" /> 

      <category android:name="android.intent.category.DEFAULT" /> 
     </intent-filter> 
    </activity> 
    <activity 
     android:name="com.example.thebasicseries.TutorialOne" 
     android:label="@string/app_name" > 
     <intent-filter> 
      <action android:name="com.example.thebasicseries.TutorialOne" /> 

      <category android:name="android.intent.category.DEFAULT" /> 
     </intent-filter> 
    </activity> 
</application> 

</manifest> 

Журнал ошибок состоит в следующем:

 04-20 11:13:29.780: E/AndroidRuntime(820): FATAL EXCEPTION: main 
    04-20 11:13:29.780: E/AndroidRuntime(820): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.thebasicseries/com.example.thebasicseries.menu}: java.lang.NullPointerException 
    04-20 11:13:29.780: E/AndroidRuntime(820):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2180) 
    04-20 11:13:29.780: E/AndroidRuntime(820):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230) 
    04-20 11:13:29.780: E/AndroidRuntime(820): at android.app.ActivityThread.access$600(ActivityThread.java:141) 
    04-20 11:13:29.780: E/AndroidRuntime(820): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234) 
    04-20 11:13:29.780: E/AndroidRuntime(820): at android.os.Handler.dispatchMessage(Handler.java:99) 
    04-20 11:13:29.780: E/AndroidRuntime(820): at android.os.Looper.loop(Looper.java:137) 
    04-20 11:13:29.780: E/AndroidRuntime(820): at android.app.ActivityThread.main(ActivityThread.java:5039) 
    04-20 11:13:29.780: E/AndroidRuntime(820): at java.lang.reflect.Method.invokeNative(Native Method) 
    04-20 11:13:29.780: E/AndroidRuntime(820): at java.lang.reflect.Method.invoke(Method.java:511) 
    04-20 11:13:29.780: E/AndroidRuntime(820): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793) 
    04-20 11:13:29.780: E/AndroidRuntime(820): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560) 
    04-20 11:13:29.780: E/AndroidRuntime(820): at dalvik.system.NativeStart.main(Native Method) 
    04-20 11:13:29.780: E/AndroidRuntime(820): Caused by: java.lang.NullPointerException 
    04-20 11:13:29.780: E/AndroidRuntime(820): at com.example.thebasicseries.menu.onCreate(menu.java:35) 
    04-20 11:13:29.780: E/AndroidRuntime(820): at android.app.Activity.performCreate(Activity.java:5104) 
    04-20 11:13:29.780: E/AndroidRuntime(820): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080) 
    04-20 11:13:29.780: E/AndroidRuntime(820): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144) 
    04-20 11:13:29.780: E/AndroidRuntime(820): ... 11 more 
    04-20 11:13:33.220: I/Process(820): Sending signal. PID: 820 SIG: 9 

Спасибо! `

Answer 1

Проблема здесь:

com.example.thebasicseries.menu.onCreate(menu.java:35) 

Вы получаете NullPointerException.

Похоже, у вас нет кнопки Tutorial2 в вашем формате XML.