声音不会播放android

 package com.droidnova.android;

 import android.app.Activity;
 import android.content.Intent;
 import android.media.MediaPlayer;
 import android.os.Bundle;
 import android.view.MotionEvent;
 import android.R;


 public class SplashScreen extends Activity {
protected boolean _active = true;
protected int _splashTime = 5000;

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.splash);

    MediaPlayer mpSplash = MediaPlayer.create(this, R.raw.laugh);
    mpSplash.start();

    // thread for displaying the SplashScreen
    Thread splashTread = new Thread() {
        @Override
        public void run() {
            try {
                int waited = 0;
                while(_active && (waited < _splashTime)) {
                    sleep(100);
                    if(_active) {
                        waited += 100;
                    }
                }
            } catch(InterruptedException e) {
                // do nothing
            } finally {
                finish();
                startActivity(new Intent(\"com.droidnova.android.splashscreen.MyApp\"));
                stop();
            }
        }
    };
    splashTread.start();
}

@Override
public boolean onTouchEvent(MotionEvent event) {
    if (event.getAction() == MotionEvent.ACTION_DOWN) {
        _active = false;
    }
    return true;
     }
}

 <?xml version=\"1.0\" encoding=\"utf-8\"?>
 <manifest xmlns:android=\"http://schemas.android.com/apk/res/android\"
  package=\"com.droidnova.android\"
  android:versionCode=\"1\"
  android:versionName=\"1.0\">
 <application android:icon=\"@drawable/icon\" android:label=\"@string/app_name\">
    <activity android:name=\".SplashScreen\"
              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=\".MyApp\">
        <intent-filter>
            <action android:name=\"com.droidnova.android.splashscreen.MyApp\" />
            <category android:name=\"android.intent.category.DEFAULT\" />
        </intent-filter>
    </activity>
 </application>
 <uses-sdk android:minSdkVersion=\"4\" />
 </manifest>

error: Error: No resource found that matches the given name (at \'label\' with value \'@string/ app_name\').

error: Error: No resource found that matches the given name (at \'label\' with value \'@string/ app_name\').

 /* AUTO-GENERATED FILE.  DO NOT MODIFY.
  *
  * This class was automatically generated by the
  * aapt tool from the resource data it found.  It
  * should not be modified by hand.
  */

 package com.droidnova.android;

 public final class R {
     public static final class attr {
}
public static final class drawable {
    public static final int icon=0x7f020000;
}
public static final class id {
    public static final int textView1=0x7f050000;
}
public static final class layout {
    public static final int main=0x7f030000;
    public static final int splash=0x7f030001;
}
public static final class string {
    public static final int app_name=0x7f040000;
    public static final int main_screen=0x7f040001;
    public static final int splash_screen=0x7f040002;
}
}