关于闪退的问题

就这次作业我在小米2上（L版本，应该是5.1）的系统上可以正常运行。后来试了一下，在小米6和三星上都是直接闪退（N版本），但是我检查了gradle   25应该是N版本呀。代码也很简单。为啥会有闪退

在小米6上抓到的applog在如下，很奇怪为什么会找不到类，想了很多办法都不奏效。

06-03 06:05:19.576  3429  3429 E AndroidRuntime: FATAL EXCEPTION: main

06-03 06:05:19.576  3429  3429 E AndroidRuntime: Process: imooc.com.imooc_demo, PID: 3429

06-03 06:05:19.576  3429  3429 E AndroidRuntime: java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{imooc.com.imooc_demo/imooc.com.imooc_demo.MainActivity}: java.lang.ClassNotFoundException: Didn't find class "imooc.com.imooc_demo.MainActivity" on path: DexPathList[[zip file "/data/app/imooc.com.imooc_demo-1/base.apk"],nativeLibraryDirectories=[/data/app/imooc.com.imooc_demo-1/lib/arm64, /system/lib64, /vendor/lib64]]

06-03 06:05:19.576  3429  3429 E AndroidRuntime: at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2582)

06-03 06:05:19.576  3429  3429 E AndroidRuntime: at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2741)

06-03 06:05:19.576  3429  3429 E AndroidRuntime: at android.app.ActivityThread.-wrap12(ActivityThread.java)

06-03 06:05:19.576  3429  3429 E AndroidRuntime: at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1490)

06-03 06:05:19.576  3429  3429 E AndroidRuntime: at android.os.Handler.dispatchMessage(Handler.java:102)

06-03 06:05:19.576  3429  3429 E AndroidRuntime: at android.os.Looper.loop(Looper.java:154)

06-03 06:05:19.576  3429  3429 E AndroidRuntime: at android.app.ActivityThread.main(ActivityThread.java:6165)

06-03 06:05:19.576  3429  3429 E AndroidRuntime: at java.lang.reflect.Method.invoke(Native Method)

06-03 06:05:19.576  3429  3429 E AndroidRuntime: at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:895)

06-03 06:05:19.576  3429  3429 E AndroidRuntime: at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:785)

06-03 06:05:19.576  3429  3429 E AndroidRuntime: Caused by: java.lang.ClassNotFoundException: Didn't find class "imooc.com.imooc_demo.MainActivity" on path: DexPathList[[zip file "/data/app/imooc.com.imooc_demo-1/base.apk"],nativeLibraryDirectories=[/data/app/imooc.com.imooc_demo-1/lib/arm64, /system/lib64, /vendor/lib64]]

06-03 06:05:19.576  3429  3429 E AndroidRuntime: at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56)

06-03 06:05:19.576  3429  3429 E AndroidRuntime: at java.lang.ClassLoader.loadClass(ClassLoader.java:380)

06-03 06:05:19.576  3429  3429 E AndroidRuntime: at java.lang.ClassLoader.loadClass(ClassLoader.java:312)

06-03 06:05:19.576  3429  3429 E AndroidRuntime: at android.app.Instrumentation.newActivity(Instrumentation.java:1079)

06-03 06:05:19.576  3429  3429 E AndroidRuntime: at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2572)

06-03 06:05:19.576  3429  3429 E AndroidRuntime: ... 9 more