我尝试在 Android Studio 3.2.1 上创建一个新项目 . 在项目创建向导中，选择最小SDK版本支持为 API level 21 (Android 5.0) ，使用“ Empty Activity ”模板创建项目 .

我尝试使用和不使用“Kotlin”支持同样的结果 . 当我尝试在任何模拟器/手机上运行这个新创建的应用程序时，应用程序崩溃了 .

但是，当我将minSDK更改为小于21时，应用程序成功运行 . 当minSDK版本高于21时，它也运行良好 .

Note: The compileSDKVersion and targetSDKVersion was set to 28

这是崩溃日志 .

2018-11-10 02:25:43.886 3742-3742/? E/AndroidRuntime: FATAL EXCEPTION: main

Process: com.kbeanie.test1, PID: 3742

java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.kbeanie.test1/com.kbeanie.test1.MainActivity}: java.lang.ClassNotFoundException: Didn't find class "com.kbeanie.test1.MainActivity" on path: DexPathList[[zip file "/data/app/com.kbeanie.test1-BOVWTjJJqRM5jnzV5X3nnw==/base.apk"],nativeLibraryDirectories=[/data/app/com.kbeanie.test1-BOVWTjJJqRM5jnzV5X3nnw==/lib/x86, /system/lib, /vendor/lib]]

at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2679)

at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2856)

at android.app.ActivityThread.-wrap11(Unknown Source:0)

at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1589)

at android.os.Handler.dispatchMessage(Handler.java:106)

at android.os.Looper.loop(Looper.java:164)

at android.app.ActivityThread.main(ActivityThread.java:6494)

at java.lang.reflect.Method.invoke(Native Method)

at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)

at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)

Caused by: java.lang.ClassNotFoundException: Didn't find class "com.kbeanie.test1.MainActivity" on path: DexPathList[[zip file "/data/app/com.kbeanie.test1-BOVWTjJJqRM5jnzV5X3nnw==/base.apk"],nativeLibraryDirectories=[/data/app/com.kbeanie.test1-BOVWTjJJqRM5jnzV5X3nnw==/lib/x86, /system/lib, /vendor/lib]]

at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:125)

at java.lang.ClassLoader.loadClass(ClassLoader.java:379)

at java.lang.ClassLoader.loadClass(ClassLoader.java:312)

at android.app.Instrumentation.newActivity(Instrumentation.java:1174)

at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2669)

at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2856)

at android.app.ActivityThread.-wrap11(Unknown Source:0)

at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1589)

at android.os.Handler.dispatchMessage(Handler.java:106)

at android.os.Looper.loop(Looper.java:164)

at android.app.ActivityThread.main(ActivityThread.java:6494)

at java.lang.reflect.Method.invoke(Native Method)

at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)

at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)

Suppressed: java.lang.NoClassDefFoundError: Failed resolution of: Landroid/support/v7/app/AppCompatActivity;

at java.lang.VMClassLoader.findLoadedClass(Native Method)

at java.lang.ClassLoader.findLoadedClass(ClassLoader.java:738)

at java.lang.ClassLoader.loadClass(ClassLoader.java:363)

... 12 more

Caused by: java.lang.ClassNotFoundException: android.support.v7.app.AppCompatActivity

at java.lang.VMClassLoader.findLoadedClass(Native Method)

at java.lang.ClassLoader.findLoadedClass(ClassLoader.java:738)

at java.lang.ClassLoader.loadClass(ClassLoader.java:363)

at java.lang.ClassLoader.loadClass(ClassLoader.java:312)

... 15 more

Caused by: java.lang.NoClassDefFoundError: Failed resolution of: Landroid/support/v4/app/FragmentActivity;

... 15 more

Caused by: java.lang.ClassNotFoundException: android.support.v4.app.FragmentActivity

at java.lang.VMClassLoader.findLoadedClass(Native Method)

at java.lang.ClassLoader.findLoadedClass(ClassLoader.java:738)

at java.lang.ClassLoader.loadClass(ClassLoader.java:363)

at java.lang.ClassLoader.loadClass(ClassLoader.java:312)

... 15 more

Caused by: java.lang.NoClassDefFoundError: Failed resolution of: Landroid/support/v4/app/SupportActivity;

... 15 more

Caused by: java.lang.ClassNotFoundException: android.support.v4.app.SupportActivity

at java.lang.VMClassLoader.findLoadedClass(Native Method)

at java.lang.ClassLoader.findLoadedClass(ClassLoader.java:738)

at java.lang.ClassLoader.loadClass(ClassLoader.java:363)

at java.lang.ClassLoader.loadClass(ClassLoader.java:312)

... 15 more

Caused by: java.lang.NoClassDefFoundError: Failed resolution of: Landroid/arch/lifecycle/LifecycleOwner;

... 15 more

Caused by: java.lang.ClassNotFoundException: Didn't find class "android.arch.lifecycle.LifecycleOwner" on path: DexPathList[[zip file "/data/app/com.kbeanie.test1-BOVWTjJJqRM5jnzV5X3nnw==/base.apk"],nativeLibraryDirectories=[/data/app/com.kbeanie.test1-BOVWTjJJqRM5jnzV5X3nnw==/lib/x86, /system/lib, /vendor/lib]]

at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:125)

at java.lang.ClassLoader.loadClass(ClassLoader.java:379)

at java.lang.ClassLoader.loadClass(ClassLoader.java:312)

... 15 more

这是build.gradle文件的内容 .

apply plugin: 'com.android.application'

android {

compileSdkVersion 28

defaultConfig {

applicationId "com.kbeanie.test2"

minSdkVersion 15

targetSdkVersion 28

versionCode 1

versionName "1.0"

testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"

}

buildTypes {

release {

minifyEnabled false

proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'

}

}

}

dependencies {

implementation fileTree(dir: 'libs', include: ['*.jar'])

implementation 'com.android.support:appcompat-v7:28.0.0'

implementation 'com.android.support.constraint:constraint-layout:1.1.3'

testImplementation 'junit:junit:4.12'

androidTestImplementation 'com.android.support.test:runner:1.0.2'

androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'

}