我正在将项目导入我的工作区并尝试运行它。没有错误，启动画面完美启动。但是，在启动主活动时，应用程序崩溃并出现NoClassDefFound错误。这是logcat
07-29 12:41:13.388: E/AndroidRuntime(31120): FATAL EXCEPTION: main
07-29 12:41:13.388: E/AndroidRuntime(31120): Process: com.dginc.laughrt, PID: 31120
07-29 12:41:13.388: E/AndroidRuntime(31120): java.lang.NoClassDefFoundError: Failed resolution of: Lcom/dginc/laughrt/MainActivity;
07-29 12:41:13.388: E/AndroidRuntime(31120): at com.dginc.laughrt.SplashActivity$1.run(SplashActivity.java:23)
07-29 12:41:13.388: E/AndroidRuntime(31120): at android.os.Handler.handleCallback(Handler.java:739)
07-29 12:41:13.388: E/AndroidRuntime(31120): at android.os.Handler.dispatchMessage(Handler.java:95)
07-29 12:41:13.388: E/AndroidRuntime(31120): at android.os.Looper.loop(Looper.java:135)
07-29 12:41:13.388: E/AndroidRuntime(31120): at android.app.ActivityThread.main(ActivityThread.java:5254)
07-29 12:41:13.388: E/AndroidRuntime(31120): at java.lang.reflect.Method.invoke(Native Method)
07-29 12:41:13.388: E/AndroidRuntime(31120): at java.lang.reflect.Method.invoke(Method.java:372)
07-29 12:41:13.388: E/AndroidRuntime(31120): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
07-29 12:41:13.388: E/AndroidRuntime(31120): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
07-29 12:41:13.388: E/AndroidRuntime(31120): Caused by: java.lang.ClassNotFoundException: Didn't find class "com.dginc.laughrt.MainActivity" on path: DexPathList[[zip file "/data/app/com.dginc.laughrt-1/base.apk"],nativeLibraryDirectories=[/vendor/lib, /system/lib]]
07-29 12:41:13.388: E/AndroidRuntime(31120): at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56)
07-29 12:41:13.388: E/AndroidRuntime(31120): at java.lang.ClassLoader.loadClass(ClassLoader.java:511)
07-29 12:41:13.388: E/AndroidRuntime(31120): at java.lang.ClassLoader.loadClass(ClassLoader.java:469)
07-29 12:41:13.388: E/AndroidRuntime(31120): ... 9 more
07-29 12:41:13.388: E/AndroidRuntime(31120): Suppressed: java.lang.NoClassDefFoundError: com.dginc.laughrt.MainActivity
07-29 12:41:13.388: E/AndroidRuntime(31120): at dalvik.system.DexFile.defineClassNative(Native Method)
07-29 12:41:13.388: E/AndroidRuntime(31120): at dalvik.system.DexFile.defineClass(DexFile.java:226)
07-29 12:41:13.388: E/AndroidRuntime(31120): at dalvik.system.DexFile.loadClassBinaryName(DexFile.java:219)
07-29 12:41:13.388: E/AndroidRuntime(31120): at dalvik.system.DexPathList.findClass(DexPathList.java:321)
07-29 12:41:13.388: E/AndroidRuntime(31120): at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:54)
07-29 12:41:13.388: E/AndroidRuntime(31120): ... 11 more
07-29 12:41:13.388: E/AndroidRuntime(31120): Suppressed: java.lang.ClassNotFoundException: com.dginc.laughrt.MainActivity
07-29 12:41:13.388: E/AndroidRuntime(31120): at java.lang.Class.classForName(Native Method)
07-29 12:41:13.388: E/AndroidRuntime(31120): at java.lang.BootClassLoader.findClass(ClassLoader.java:781)
07-29 12:41:13.388: E/AndroidRuntime(31120): at java.lang.BootClassLoader.loadClass(ClassLoader.java:841)
07-29 12:41:13.388: E/AndroidRuntime(31120): at java.lang.ClassLoader.loadClass(ClassLoader.java:504)
07-29 12:41:13.388: E/AndroidRuntime(31120): ... 10 more
07-29 12:41:13.388: E/AndroidRuntime(31120): Caused by: java.lang.NoClassDefFoundError: Class not found using the boot class loader; no stack available
这是我项目的清单文件
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.dginc.laughrt"
android:versionCode="3"
android:versionName="2.0" >
<uses-sdk
android:minSdkVersion="15"
android:targetSdkVersion="19" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_SETTINGS" >
</uses-permission>
<uses-permission android:name="android.permission.READ_CONTACTS" />
<uses-permission android:name="android.permission.WRITE_CONTACTS" />
<application
android:allowBackup="true"
android:hardwareAccelerated="true"
android:icon="@drawable/justlaughicon1"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.dginc.laughrt.SplashActivity"
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.dginc.laughrt.MainActivity"
android:label="@string/app_name" >
</activity>
<activity
android:name="com.dginc.laughrt.Second"
android:label="@string/app_name" >
</activity>
<service
android:name="com.dginc.laughrt.MediaPlayerService"
android:enabled="true" >
</service>
<meta-data
android:name="com.google.android.gms.version"
android:value="@integer/google_play_services_version" />
<activity
android:name="com.google.android.gms.ads.AdActivity"
android:configChanges="keyboard|keyboardHidden|orientation|screenLayout|uiMode|screenSize|smallestScreenSize" />
<activity
android:name="com.chartboost.sdk.CBImpressionActivity"
android:excludeFromRecents="true"
android:theme="@android:style/Theme.Translucent.NoTitleBar" />
<activity android:name="com.startapp.android.publish.list3d.List3DActivity"
android:theme="@android:style/Theme" />
<activity android:name="com.startapp.android.publish.OverlayActivity"
android:theme="@android:style/Theme.Translucent"
android:configChanges="orientation|keyboardHidden|screenSize" />
<activity android:name="com.startapp.android.publish.FullScreenActivity"
android:theme="@android:style/Theme"
android:configChanges="orientation|keyboardHidden|screenSize" />
</application>
</manifest>
请帮帮我。