我试图在我的应用程序中使用AndroidX库，但是遇到了问题。我了解与Firebase相关的问题。如您所见，我排除了支持v4库，这是有原因的。如果我删除这些行，则会出现另一个错误：“程序类型已存在：android.support.v4.media.MediaBrowserCompat $ ConnectionCallback $ StubApi21”。那么，如何一起使用AndroidX和Firebase？有什么解决办法吗？
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.ignes.androidxtest, PID: 30800
java.lang.NoClassDefFoundError: Failed resolution of: Landroid/support/v4/util/ArrayMap;
at com.google.firebase.FirebaseApp.<clinit>(SourceFile:135)
at com.google.firebase.FirebaseApp.initializeApp(SourceFile:273)
at com.google.firebase.provider.FirebaseInitProvider.onCreate(SourceFile:37)
at android.content.ContentProvider.attachInfo(ContentProvider.java:1696)
at android.content.ContentProvider.attachInfo(ContentProvider.java:1671)
at com.google.firebase.provider.FirebaseInitProvider.attachInfo(SourceFile:31)
at android.app.ActivityThread.installProvider(ActivityThread.java:5084)
at android.app.ActivityThread.installContentProviders(ActivityThread.java:4679)
at android.app.ActivityThread.handleBindApplication(ActivityThread.java:4619)
at android.app.ActivityThread.access$1500(ActivityThread.java:155)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1378)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5343)
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:905)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:700)
Caused by: java.lang.ClassNotFoundException: Didn't find class "android.support.v4.util.ArrayMap" on path: DexPathList[[zip file "/data/app/com.ignes.androidxtest-2/base.apk", zip file "/data/app/com.ignes.androidxtest-2/split_lib_dependencies_apk.apk", zip file "/data/app/com.ignes.androidxtest-2/split_lib_slice_0_apk.apk", zip file "/data/app/com.ignes.androidxtest-2/split_lib_slice_1_apk.apk", zip file "/data/app/com.ignes.androidxtest-2/split_lib_slice_2_apk.apk", zip file "/data/app/com.ignes.androidxtest-2/split_lib_slice_3_apk.apk", zip file "/data/app/com.ignes.androidxtest-2/split_lib_slice_4_apk.apk", zip file "/data/app/com.ignes.androidxtest-2/split_lib_slice_5_apk.apk", zip file "/data/app/com.ignes.androidxtest-2/split_lib_slice_6_apk.apk", zip file "/data/app/com.ignes.androidxtest-2/split_lib_slice_7_apk.apk", zip file "/data/app/com.ignes.androidxtest-2/split_lib_slice_8_apk.apk", zip file "/data/app/com.ignes.androidxtest-2/split_lib_slice_9_apk.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)
at com.google.firebase.FirebaseApp.<clinit>(SourceFile:135)
at com.google.firebase.FirebaseApp.initializeApp(SourceFile:273)
at com.google.firebase.provider.FirebaseInitProvider.onCreate(SourceFile:37)
at android.content.ContentProvider.attachInfo(ContentProvider.java:1696)
at android.content.ContentProvider.attachInfo(ContentProvider.java:1671)
at com.google.firebase.provider.FirebaseInitProvider.attachInfo(SourceFile:31)
at android.app.ActivityThread.installProvider(ActivityThread.java:5084)
at android.app.ActivityThread.installContentProviders(ActivityThread.java:4679)
at android.app.ActivityThread.handleBindApplication(ActivityThread.java:4619)
at android.app.ActivityThread.access$1500(ActivityThread.java:155)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1378)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5343)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:905)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:700)
Suppressed: java.lang.ClassNotFoundException: android.support.v4.util.ArrayMap
at java.lang.Class.classForName(Native Method)
at java.lang.BootClassLoader.findClass(ClassLoader.java:781)
at java.lang.BootClassLoader.loadClass(ClassLoader.java:841)
at java.lang.ClassLoader.loadClass(ClassLoader.java:504)
... 19 more
Caused by: java.lang.NoClassDefFoundError: Class not found using the boot class loader; no stack available
我的build.gradle是
apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply plugin: 'kotlin-android-extensions'
android {
compileSdkVersion 28
defaultConfig {
applicationId "com.testng.androidxtest"
minSdkVersion 15
targetSdkVersion 28
versionCode 1
versionName "1.0"
testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
}
configurations.all {
resolutionStrategy {
force 'androidx.legacy:legacy-support-v4:1.0.0-rc01'
}
}
dependencies {
implementation fileTree(dir: 'libs', include: ['*.jar'])
implementation"org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
implementation 'androidx.appcompat:appcompat:1.0.0-rc01'
implementation 'androidx.legacy:legacy-support-v4:1.0.0-rc01'
implementation 'androidx.constraintlayout:constraintlayout:1.1.2'
testImplementation 'junit:junit:4.12'
androidTestImplementation 'androidx.test:runner:1.1.0-alpha4'
androidTestImplementation 'androidx.test.espresso:espresso-core:3.1.0-alpha4'
implementation ('com.google.android.gms:play-services-ads:15.0.1') {
exclude group: 'com.android.support'
exclude module: 'support-v4'
}
implementation ('com.google.firebase:firebase-core:16.0.1') {
exclude group: 'com.android.support'
exclude module: 'support-v4'
}
}
答案 0 :(得分：0)
将gradle版本更改为：classpath 'com.android.tools.build:gradle:3.3.0-alpha07'，然后查看是否有效。
答案 1 :(得分：0)
我需要将Android Studio更新为版本3.2.1