无法解析符号 AppCompatActivity

Question

虽然之前已经问过这个问题，但没有一个解决方案对我有用。

问题是突然间Android Studio开始抛出Cannot resolve symbol AppCompatActivity的错误。 在我的 Windows 上单击 Alt+Enter 时，它会显示我

Add library 'com.android.support:appcompat-v7:27.0.2' to classpath

作为选项之一。

即使我的 gradle 中有以下依赖项，它一直工作到今天

implementation 'com.android.support:appcompat-v7:27.1.1'

到目前为止我已经尝试过

1. 清洁工程
2. 使缓存无效并重新启动
3. 从 .idea 文件夹中删除库文件夹并重新启动工作室
4. 关闭并重新打开项目
5. 从 gradle 中删除依赖项，与 gradle 同步并再次添加依赖项

这些解决方案都不起作用，我无法理解问题是什么。 这已经最终浪费了大量的开发时间。 有人可以帮忙吗。 谢谢！

编辑：添加依赖项

dependencies {
    implementation project(':ratemyapp')
    implementation 'com.google.code.gson:gson:2.8.2'
    implementation 'com.mcxiaoke.volley:library:1.0.18'

    implementation 'com.android.support:multidex:1.0.3'
    implementation files('libs/gcm.jar')

    // Facebook SDK Core only (Analytics)
    implementation 'com.facebook.android:facebook-core:4.33.0'

    // Facebook Login only
    implementation 'com.facebook.android:facebook-login:4.33.0'
    implementation 'com.braintreepayments.api:braintree:2.14.2'
    implementation 'com.braintreepayments.api:drop-in:3.4.0'

    implementation 'com.android.support:support-v4:27.1.1'
    implementation 'com.android.support:customtabs:27.1.1'
    implementation 'com.android.support:animated-vector-drawable:27.1.1'

    /**
     * Google
     */
    implementation 'com.google.android.gms:strict-version-matcher-plugin:1.1.0'
    implementation 'com.google.android.gms:play-services-auth:16.0.1'
    implementation 'com.google.android.gms:play-services-base:16.0.1'
    implementation 'com.google.android.gms:play-services-maps:16.0.0'
    implementation 'com.google.android.gms:play-services-identity:16.0.0'
    implementation 'com.google.android.gms:play-services-location:16.0.0'
    implementation 'com.google.android.gms:play-services-places:16.0.0'
    implementation 'com.google.android.gms:play-services-nearby:16.0.0'
    implementation 'com.google.android.gms:play-services-gcm:16.0.0'
    implementation 'com.android.support:appcompat-v7:27.1.1'
    implementation 'com.android.support:mediarouter-v7:27.1.1'
    implementation 'com.google.android:flexbox:0.3.2'

    //compile files('libs/splunk-mint-4.2.1.jar')
    implementation 'com.android.support:design:27.1.1'

    // CardView
    implementation 'com.android.support:cardview-v7:27.1.1'
    implementation 'com.pixplicity.multiviewpager:library:1.0'
    implementation 'com.github.aakira:expandable-layout:1.4.1@aar'
    implementation 'me.everything:overscroll-decor-android:1.0.4'
    implementation 'org.apache.httpcomponents:httpmime:4.5.2'
    implementation 'commons-net:commons-net:3.3'
    implementation 'com.android.support:percent:27.1.1'


    /*For Request Server*/
    implementation 'com.squareup.okhttp3:logging-interceptor:3.9.1'
    implementation 'com.squareup.retrofit2:retrofit:2.3.0'
    implementation 'com.squareup.retrofit2:converter-gson:2.3.0'
    implementation 'com.squareup.retrofit2:adapter-rxjava:2.3.0'
    implementation 'com.artemzin.rxjava:proguard-rules:1.1.6.0'

    /**
     * Animation.
     */
    implementation 'com.nineoldandroids:library:2.4.0'
    implementation 'com.daimajia.easing:library:1.0.1@aar'
    implementation 'com.daimajia.androidanimations:library:1.1.3@aar'
    implementation 'net.soulwolf.widget:ratiolayout:1.0.0'
    implementation 'com.jakewharton:butterknife:8.5.1'
    kapt 'com.jakewharton:butterknife-compiler:8.5.1'

    /**
     * Event Bus.
     */
    implementation 'org.greenrobot:eventbus:3.0.0'
    implementation 'com.wefika:flowlayout:0.4.1'

    /**
     * Ring capcha
     */
    implementation 'com.thrivecom:ringcaptcha:1.0.11@aar'

    /**
     * Zendesk
     */
    implementation 'com.zopim.android:sdk:1.3.7.1'
    implementation 'com.zendesk:support:2.0.0'
    implementation('com.twitter.sdk.android:twitter:3.3.0@aar') {
        transitive = true
    }
    implementation('com.crashlytics.sdk.android:crashlytics:2.9.3@aar') {
        transitive = true
    }
    implementation('io.fabric.sdk.android:fabric:1.3.12@aar') {
        transitive = true
    }
    implementation 'io.branch.sdk.android:library:2.5.9'

    implementation 'com.mixpanel.android:mixpanel-android:5.+'
    implementation 'com.yqritc:android-scalablevideoview:1.0.4'
    implementation 'com.android.support:cardview-v7:27.1.1'
    implementation 'com.android.support:recyclerview-v7:27.1.1'
    implementation 'com.google.dagger:dagger:2.12'
    kapt 'com.google.dagger:dagger-compiler:2.11'
    implementation 'com.google.dagger:dagger-android-support:2.11'
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
    kapt 'com.google.dagger:dagger-android-processor:2.11'

    // ViewModel and LiveData
    implementation 'android.arch.lifecycle:extensions:1.1.1'
    kapt "android.arch.lifecycle:compiler:1.1.1"

    // Room
    implementation 'android.arch.persistence.room:runtime:1.1.1'
    kapt "android.arch.persistence.room:compiler:1.1.1"

    // Paging
    implementation 'android.arch.paging:runtime:1.0.1'
    implementation 'com.jakewharton.timber:timber:4.6.0'

    // Test helpers for LiveData
    testImplementation 'android.arch.core:core-testing:1.1.1'

    // Test helpers for Room
    testImplementation 'android.arch.persistence.room:testing:1.1.1'
    implementation 'org.apache.commons:commons-lang3:3.6'
    implementation 'com.github.bumptech.glide:glide:4.5.0'
    kapt 'com.github.bumptech.glide:compiler:4.4.0'
    implementation 'com.github.rubensousa:gravitysnaphelper:1.5'
    implementation 'me.everything:overscroll-decor-android:1.0.4'
    implementation 'com.github.bumptech.glide:recyclerview-integration:4.4.0'
    implementation 'io.reactivex.rxjava2:rxjava:2.1.8'
    implementation 'io.reactivex.rxjava2:rxandroid:2.0.1'
    implementation 'android.arch.persistence.room:runtime:1.1.1'
    implementation 'android.arch.persistence.room:rxjava2:1.1.1'
    implementation 'android.arch.lifecycle:reactivestreams:1.1.1'
    implementation 'com.github.zcweng:switch-button:0.0.3@aar'
    implementation 'com.shuhart.bubblepagerindicator:bubblepagerindicator:1.0.6'
    implementation 'com.iarcuschin:simpleratingbar:0.1.5'
    implementation 'co.omise:omise-android:2.6.4'
    implementation 'com.airbnb.android:lottie:2.5.4'
    implementation 'com.adjust.sdk:adjust-android:4.13.0'
    implementation 'com.android.installreferrer:installreferrer:1.0'
    implementation 'io.card:android-sdk:5.5.1'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'android.arch.persistence.room:testing:1.1.1'
    androidTestImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test:rules:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-contrib:3.0.2'
    androidTestImplementation 'org.mockito:mockito-core:2.7.19'
    androidTestImplementation 'org.mockito:mockito-android:2.7.19'
    implementation 'net.cachapa.expandablelayout:expandablelayout:2.9.2'
    implementation project(':menu')
    implementation project(':base')
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"

    implementation 'com.google.firebase:firebase-perf:16.2.0'
    implementation 'com.google.firebase:firebase-core:16.0.4'
    implementation 'com.google.firebase:firebase-analytics:16.0.4'
    implementation 'com.google.firebase:firebase-appindexing:16.0.2'
    implementation 'com.google.firebase:firebase-messaging:17.3.4'

    implementation 'com.google.android.instantapps:instantapps:1.1.0'

    implementation 'com.romandanylyk:pageindicatorview:1.0.2'
    implementation 'com.airbnb.android:lottie:2.5.4'
    implementation 'me.grantland:autofittextview:0.2.+'

    //OTP
    implementation 'com.poovam:pin-edittext-field:1.1.2'

    implementation 'jp.wasabeef:glide-transformations:4.0.1'

}

编辑：顶级gradle文件

// Top-level build file where you can add configuration options common to all sub-projects/modules.
ext {
    compileSdkVersion = 27
    minSdkVersion = 16
    targetSdkVersion = 27
    zendeskSdkVersion = "2.0.0"
    appCompatVersion = "27.0.2"
}

buildscript {
    ext.kotlin_version = '1.2.71'
    repositories {
        google()
        jcenter()
        mavenCentral()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.2.1'
        classpath 'com.google.gms:google-services:4.2.0'
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
        classpath 'com.google.firebase:firebase-plugins:1.1.5'
    }
}
allprojects {
    repositories {
        google()
        mavenCentral()
        jcenter()
    }
}

尝试构建项目时记录

org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':MyModule:kaptDebugKotlin'.
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:103)
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:73)
    at org.gradle.api.internal.tasks.execution.OutputDirectoryCreatingTaskExecuter.execute(OutputDirectoryCreatingTaskExecuter.java:51)
    at org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter.execute(SkipUpToDateTaskExecuter.java:59)
    at org.gradle.api.internal.tasks.execution.ResolveTaskOutputCachingStateExecuter.execute(ResolveTaskOutputCachingStateExecuter.java:54)
    at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:59)
    at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:101)
    at org.gradle.api.internal.tasks.execution.FinalizeInputFilePropertiesTaskExecuter.execute(FinalizeInputFilePropertiesTaskExecuter.java:44)
    at org.gradle.api.internal.tasks.execution.CleanupStaleOutputsExecuter.execute(CleanupStaleOutputsExecuter.java:91)
    at org.gradle.api.internal.tasks.execution.ResolveTaskArtifactStateTaskExecuter.execute(ResolveTaskArtifactStateTaskExecuter.java:62)
    at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:59)
    at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:54)
    at org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter.execute(ExecuteAtMostOnceTaskExecuter.java:43)
    at org.gradle.api.internal.tasks.execution.CatchExceptionTaskExecuter.execute(CatchExceptionTaskExecuter.java:34)
    at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker$1.run(DefaultTaskGraphExecuter.java:256)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:336)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:328)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:199)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:110)
    at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:249)
    at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:238)
    at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.processTask(DefaultTaskPlanExecutor.java:123)
    at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.access$200(DefaultTaskPlanExecutor.java:79)
    at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker$1.execute(DefaultTaskPlanExecutor.java:104)
    at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker$1.execute(DefaultTaskPlanExecutor.java:98)
    at org.gradle.execution.taskgraph.DefaultTaskExecutionPlan.execute(DefaultTaskExecutionPlan.java:663)
    at org.gradle.execution.taskgraph.DefaultTaskExecutionPlan.executeWithTask(DefaultTaskExecutionPlan.java:597)
    at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.run(DefaultTaskPlanExecutor.java:98)
    at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:63)
    at org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:46)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at org.gradle.internal.concurrent.ThreadFactoryImpl$ManagedThreadRunnable.run(ThreadFactoryImpl.java:55)
    at java.lang.Thread.run(Thread.java:745)
Caused by: org.gradle.api.GradleException: Compilation error. See log for more details
    at org.jetbrains.kotlin.gradle.tasks.TasksUtilsKt.throwGradleExceptionIfError(tasksUtils.kt:16)
    at org.jetbrains.kotlin.gradle.internal.KaptWithKotlincTask.compile(KaptWithKotlincTask.kt:79)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.gradle.internal.reflect.JavaMethod.invoke(JavaMethod.java:73)
    at org.gradle.api.internal.project.taskfactory.StandardTaskAction.doExecute(StandardTaskAction.java:46)
    at org.gradle.api.internal.project.taskfactory.StandardTaskAction.execute(StandardTaskAction.java:39)
    at org.gradle.api.internal.project.taskfactory.StandardTaskAction.execute(StandardTaskAction.java:26)
    at org.gradle.api.internal.AbstractTask$TaskActionWrapper.execute(AbstractTask.java:788)
    at org.gradle.api.internal.AbstractTask$TaskActionWrapper.execute(AbstractTask.java:755)
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter$1.run(ExecuteActionsTaskExecuter.java:124)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:336)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:328)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:199)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:110)
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeAction(ExecuteActionsTaskExecuter.java:113)
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:95)
    ... 33 more

Answer 1

首先检查这个答案stackoverflow

第二次更新您的版本将所有 27.1.1 更改为 28.0.0 也更改

compileSdkVersion = 28
targetSdkVersion = 28

您的代码中有一些错误：

1）您的依赖项中有 2 个 cardview

2）你不使用这个分机

ext {
    compileSdkVersion = 27
    minSdkVersion = 16
    targetSdkVersion = 27
    zendeskSdkVersion = "2.0.0"
    appCompatVersion = "27.0.2"
}

Answer 2

感谢大家的帮助，但是我不得不卸载并重新安装Android Studio ，然后错误消失了。