eclipse java.lang.RuntimeException: 无法实例化活动 ComponentInfo{…}: java.lang.ClassNotFoundException: 没有找到类
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java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{…}: java.lang.ClassNotFoundException: Didn't find class
提问by user3908478
I am developing an app using Fused Location Provider. I am getting an error "Unfortunately, appname has stopped" when i attempt to run the program. Eclipse doesnt show that there are any mistakes but there are errors in the logcat. I dont know how to fix them. I downloaded source code here. Please help me to understand what I did wrong?
我正在使用 Fused Location Provider 开发应用程序。当我尝试运行该程序时，出现错误“不幸的是，appname 已停止”。Eclipse 不显示有任何错误，但 logcat 中有错误。我不知道如何修复它们。我在这里下载了源代码。请帮我理解我做错了什么？
LogCat
日志猫
11-05 08:31:41.641: E/AndroidRuntime(795): FATAL EXCEPTION: main
11-05 08:31:41.641: E/AndroidRuntime(795): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.kpbird.fusedlocation/com.kpbird.fusedlocation.MainActivity}: java.lang.ClassNotFoundException: Didn't find class "com.kpbird.fusedlocation.MainActivity" on path: DexPathList[[zip file "/data/app/com.kpbird.fusedlocation-1.apk"],nativeLibraryDirectories=[/data/app-lib/com.kpbird.fusedlocation-1, /system/lib]]
11-05 08:31:41.641: E/AndroidRuntime(795): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2137)
11-05 08:31:41.641: E/AndroidRuntime(795): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2261)
11-05 08:31:41.641: E/AndroidRuntime(795): at android.app.ActivityThread.access0(ActivityThread.java:141)
11-05 08:31:41.641: E/AndroidRuntime(795): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1256)
11-05 08:31:41.641: E/AndroidRuntime(795): at android.os.Handler.dispatchMessage(Handler.java:99)
11-05 08:31:41.641: E/AndroidRuntime(795): at android.os.Looper.loop(Looper.java:137)
11-05 08:31:41.641: E/AndroidRuntime(795): at android.app.ActivityThread.main(ActivityThread.java:5103)
11-05 08:31:41.641: E/AndroidRuntime(795): at java.lang.reflect.Method.invokeNative(Native Method)
11-05 08:31:41.641: E/AndroidRuntime(795): at java.lang.reflect.Method.invoke(Method.java:525)
11-05 08:31:41.641: E/AndroidRuntime(795): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
11-05 08:31:41.641: E/AndroidRuntime(795): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
11-05 08:31:41.641: E/AndroidRuntime(795): at dalvik.system.NativeStart.main(Native Method)
11-05 08:31:41.641: E/AndroidRuntime(795): Caused by: java.lang.ClassNotFoundException: Didn't find class "com.kpbird.fusedlocation.MainActivity" on path: DexPathList[[zip file "/data/app/com.kpbird.fusedlocation-1.apk"],nativeLibraryDirectories=[/data/app-lib/com.kpbird.fusedlocation-1, /system/lib]]
11-05 08:31:41.641: E/AndroidRuntime(795): at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:53)
11-05 08:31:41.641: E/AndroidRuntime(795): at java.lang.ClassLoader.loadClass(ClassLoader.java:501)
11-05 08:31:41.641: E/AndroidRuntime(795): at java.lang.ClassLoader.loadClass(ClassLoader.java:461)
11-05 08:31:41.641: E/AndroidRuntime(795): at android.app.Instrumentation.newActivity(Instrumentation.java:1061)
11-05 08:31:41.641: E/AndroidRuntime(795): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2128)
11-05 08:31:41.641: E/AndroidRuntime(795): ... 11 more
采纳答案by Jorgesys
Since your exception is:
由于您的例外是：
ClassNotFoundException: Didn't find class "com.kpbird.fusedlocation.MainActivity"
into your AndroidManifest.xmladd the complete package were your activity is located:
AndroidManifest.xml添加到您的活动所在的完整包中：
<activity
android:name="com.kpbird.fusedlocation.MainActivity"
or be sure to have to correct package name defined:
或者一定要更正定义的包名：
package="com.kpbird.fusedlocation"
I think you typed incorrectly the package of your application in some place of your code!
我认为您在代码的某个位置错误地输入了应用程序的包！
回答by EmmanuelMess
This happened when I moved an app from one directory to another once, if @Jorgesys's solutiondoesn't help, consider renaming the module and cleaning the project. Note: I was using Android Studio.
当我将应用程序从一个目录移动到另一个目录时发生了这种情况，如果@Jorgesys 的解决方案没有帮助，请考虑重命名模块并清理项目。注意：我使用的是 Android Studio。
回答by AnR
While updating my MainActivity.java I accidentally changed my package name from package com.ppg;to package com.PPG;(upper case instead of lower case). When I changed back to lower case it started working.
在更新我的 MainActivity.java 时，我不小心将包名从 更改package com.ppg;为package com.PPG;（大写而不是小写）。当我改回小写时，它开始工作。
回答by Jacob
The same issue occurs while including in AndroidManifestreference with:
在AndroidManifest引用以下内容时会发生同样的问题：
<meta-data
android:name="com.google.android.gms.version"
android:value="@integer/google_play_services_version" />
and hardcoded wrong google_play_services_versionvalue.
并硬编码错误google_play_services_version值。
回答by Mehul
After spending much time on this problem i finally got the solution.
在这个问题上花了很多时间后，我终于得到了解决方案。
Just remove setContentView(R.layout.LAYOUT_NAME);from constructor of class
and put it into onCreatemethod of the class.
只需setContentView(R.layout.LAYOUT_NAME);从类的构造函数中删除并将其放入onCreate类的方法中。
100% it will be solved.
100%会解决的。
