我正在尝试使用代码启动新活动：
Intent i = new Intent(this, TempLobbyActivity.class);
startActivity(i);
finish();
当我启动此代码时，我在执行Intent构造函数时会遇到以下异常。
FATAL EXCEPTION: main
Process: com.edr.iveflownthat, PID: 1457
java.lang.NoClassDefFoundError: Failed resolution of: Lcom/edr/iveflownthat/TempLobbyActivity;
at com.edr.iveflownthat.pages.MainActivity.tryAutoLogin(MainActivity.java:46)
at com.edr.iveflownthat.pages.MainActivity.onCreate(MainActivity.java:22)
at android.app.Activity.performCreate(Activity.java:5933)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2251)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
at android.app.ActivityThread.access$800(ActivityThread.java:144)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5221)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
Caused by: java.lang.ClassNotFoundException: Didn't find class "com.edr.iveflownthat.TempLobbyActivity" on path: DexPathList[[zip file "/data/app/com.edr.iveflownthat-1/base.apk"],nativeLibraryDirectories=[/vendor/lib, /system/lib]]
FATAL EXCEPTION: main
Process: com.edr.iveflownthat, PID: 1457
java.lang.NoClassDefFoundError: Failed resolution of: Lcom/edr/iveflownthat/TempLobbyActivity;
at com.edr.iveflownthat.pages.MainActivity.tryAutoLogin(MainActivity.java:46)
at com.edr.iveflownthat.pages.MainActivity.onCreate(MainActivity.java:22)
at android.app.Activity.performCreate(Activity.java:5933)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2251)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
at android.app.ActivityThread.access$800(ActivityThread.java:144)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5221)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
Caused by: java.lang.ClassNotFoundException: Didn't find class "com.edr.iveflownthat.TempLobbyActivity" on path: DexPathList[[zip file "/data/app/com.edr.iveflownthat-1/base.apk"],nativeLibraryDirectories=[/vendor/lib, /system/lib]]
at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56)
at java.lang.ClassLoader.loadClass(ClassLoader.java:511)
at java.lang.ClassLoader.loadClass(ClassLoader.java:469)
... 15 more
Suppressed: java.lang.NoClassDefFoundError: com.edr.iveflownthat.TempLobbyActivity
at dalvik.system.DexFile.defineClassNative(Native Method)
at dalvik.system.DexFile.defineClass(DexFile.java:222)
at dalvik.system.DexFile.loadClassBinaryName(DexFile.java:215)
at dalvik.system.DexPathList.findClass(DexPathList.java:321)
at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:54)
... 17 more
Suppressed: java.lang.ClassNotFoundException: com.edr.iveflownthat.TempLobbyActivity
at java.lang.Class.classForName(Native Method)
at java.lang.BootClassLoader.findClass(ClassLoader.java:781)
at java.lang.BootClassLoader.loadClass(ClassLoader.java:841)
at java.lang.ClassLoader.loadClass(ClassLoader.java:504)
... 16 more
Caused by: java.lang.NoClassDefFoundError: Class not found using the boot class loader; no stack available at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56)
at java.lang.ClassLoader.loadClass(ClassLoader.java:511)
at java.lang.ClassLoader.loadClass(ClassLoader.java:469)
... 15 more
Suppressed: java.lang.NoClassDefFoundError: com.edr.iveflownthat.TempLobbyActivity
at dalvik.system.DexFile.defineClassNative(Native Method)
at dalvik.system.DexFile.defineClass(DexFile.java:222)
at dalvik.system.DexFile.loadClassBinaryName(DexFile.java:215)
at dalvik.system.DexPathList.findClass(DexPathList.java:321)
at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:54)
... 17 more
Suppressed: java.lang.ClassNotFoundException: com.edr.iveflownthat.TempLobbyActivity
at java.lang.Class.classForName(Native Method)
at java.lang.BootClassLoader.findClass(ClassLoader.java:781)
at java.lang.BootClassLoader.loadClass(ClassLoader.java:841)
at java.lang.ClassLoader.loadClass(ClassLoader.java:504)
... 16 more
Caused by: java.lang.NoClassDefFoundError: Class not found using the boot class loader; no stack available
我确保TempLobbyActivity类确实存在并且是一个适当的活动。我没有其他错误。
这是TempLobbyActivity的开始：
package com.edr.iveflownthat;
import android.app.Activity;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarDrawerToggle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import com.edr.iveflownthat.pages.fragments.LobbyLeaderboardFragment;
import com.edr.iveflownthat.pages.fragments.LobbyMessagerFragment;
import com.edr.iveflownthat.pages.fragments.LobbyMyPlanesFragment;
public class TempLobbyActivity extends FragmentActivity {
这是我的清单文件：
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.edr.iveflownthat"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="14"
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.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.GET_ACCOUNTS" />
<uses-permission android:name="android.permission.USE_CREDENTIALS" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<application
android:allowBackup="true"
android:icon="@drawable/app_logo"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<meta-data
android:name="com.google.android.gms.version"
android:value="@integer/google_play_services_version" />
<activity
android:name=".pages.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=".StartActivity"
android:label="@string/title_activity_start" >
</activity>
<activity
android:name=".pages.AccountLoginActivity"
android:label="@string/title_activity_login" >
</activity>
<activity
android:name=".pages.MyPlanesActivity"
android:label="@string/title_activity_my_planes" >
</activity>
<activity
android:name="com.edr.icom.edr.iveflownthat.activities.AccountNewActivity"
android:label="@string/title_activity_new_account" >
</activity>
<activity
android:name=".pages.SearchPlanesActivity"
android:label="@string/title_activity_search"
android:parentActivityName=".pages.LobbyActivity" >
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value="com.edr.iveflownthat.pages.LobbyActivity" />
</activity>
<activity
android:name=".pages.LeaderBoardActivity"
android:label="@string/title_activity_leader_board" >
</activity>
<activity
android:name=".pages.PlaneBioActivity"
android:label="@string/title_activity_plane_info" >
</activity>
<activity
android:name=".pages.AccountLoginFacebookActivity"
android:label="@string/title_activity_account_login_facebook" >
</activity>
<activity
android:name=".pages.AccountLoginGoogleActivity"
android:label="@string/title_activity_account_login_google" >
</activity>
<activity
android:name=".pages.AccountLoginTwitterActivity"
android:label="@string/title_activity_account_login_twitter" >
</activity>
<activity
android:name=".pages.SettingsActivity"
android:label="@string/title_activity_settings" >
</activity>
<activity
android:name=".pages.MainTabActivity"
android:label="@string/title_activity_main_tab" >
</activity>
<activity
android:name=".pages.LobbyActivity"
android:label="@string/title_activity_lobby" >
</activity>
<activity
android:name=".pages.MessageStreamActivity"
android:label="@string/title_activity_message_stream"
android:parentActivityName=".pages.LobbyActivity" >
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value="com.edr.iveflownthat.pages.LobbyActivity" />
</activity>
<activity
android:name=".pages.LeaderboardActivity"
android:label="@string/title_activity_leaderboard"
android:parentActivityName=".pages.LobbyActivity" >
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value="com.edr.iveflownthat.pages.LobbyActivity" />
</activity>
<service
android:name=".services.MainService"
android:exported="false" />
<activity
android:name=".pages.NewMessageActivity"
android:label="@string/title_activity_new_message" >
</activity>
<activity
android:name=".pages.PlaneActivity"
android:label="@string/title_activity_plane" >
</activity>
<!--
<meta-data
android:name="com.facebook.sdk.ApplicationId"
android:value="@string/app_id" />
<activity
android:name="com.facebook.LoginActivity"
android:label="@string/app_name" >
</activity>
-->
<activity
android:name=".TempLobbyActivity"
android:label="@string/title_activity_temp_lobby" >
</activity>
</application>
</manifest>
答案 0 :(得分：13)
即使在AndroidManifest.xml中定义了类，我也遇到了同样的错误。
原因：有时会在添加多个版本的appcompat库时发生这种情况。
解决方案：删除以前版本的appcompat lib并将appcompat_v7.jar添加到/ lib文件夹。
清理您的项目并重新构建。您可能不会再次收到错误。
答案 1 :(得分：0)
在AndroidManifest.xml注册TempLobbyActivity
<activity android:name="TempLobbyActivity"></activity>
所以你的清单文件应该是这样的
<activity android:name=".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="TempLobbyActivity"></activity>
答案 2 :(得分：0)
自11月21日以来，API级别10（Android 2.3.3 - 2.3.7）存在一个错误（可能在Play服务库中）：
请参阅此错误报告 https://code.google.com/p/android/issues/detail?id=81083
答案 3 :(得分：0)
对于那些可能仍然面临这个问题的人：
为build.gradle添加适当的依赖项，如果没有正确添加依赖项并且gradle没有编译添加到项目中的库，则会发生此类错误，因此您不会在运行时访问这些库类。
答案 4 :(得分：0)
我发现控制台中出现了一个我忽略的错误：
[ExoPlayerLib]找不到ExoPlayerLib.apk。
使用SO answer解决此问题，NoClassDefFoundError的次要错误也已解决。
看起来，在项目中构建和包含库的任何问题都可能导致此问题。