升级Android Studio后,没有问题的项目开始在编辑器中显示问题。我有很多Unresolved Reference
错误。支持库下的所有内容(support-v4,support-v7)。
在上面的屏幕截图中,红色显示的内容都没有解决,而是显示为错误。 我也在使用Lifecycle组件和Room数据库。他们似乎也有问题。看起来可以找到接口,但找不到类。
例如,在我的一个使用Room
的课程中,
android.arch.persistence.room.Database
和android.arch.persistence.room.TypeConverters
可以正确解析,但是
android.arch.persistence.room.Room
和android.arch.persistence.room.RoomDatabase
不会。
注意:该项目可以在Android模拟器和设备上正常构建并正常运行,没有任何问题。它使用Android Studio上的“构建”按钮进行构建和运行,没有任何错误。我没有收到任何Class not found错误。这只是Android Studio编辑器中的一个问题。我已经重新启动Android Studio,清理并重建了项目。
这是我的项目构建文件:
buildscript {
ext.kotlin_version = '1.2.70'
ext.serialization_version = '0.6.2'
ext.gradle_plugin_version = '3.2.0'
repositories {
google()
jcenter()
maven { url "https://jitpack.io" }
maven { url "https://kotlin.bintray.com/kotlinx" }
}
dependencies {
classpath "com.android.tools.build:gradle:3.2.1"
classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
classpath "org.jetbrains.kotlinx:kotlinx-gradle-serialization-plugin:$serialization_version"
}
}
allprojects {
repositories {
google()
jcenter()
maven { url 'https://jitpack.io' }
maven { url "https://kotlin.bintray.com/kotlinx" }
}
}
task clean(type: Delete) {
delete rootProject.buildDir
}
ext {
roomVersion = '1.1.1'
archLifecycleVersion = '1.1.1'
buildToolsVersion = '28.0.3'
supportLibVersion = '28.0.0'
}
和模块构建文件:
apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply plugin: 'kotlin-android-extensions'
apply plugin: 'kotlin-kapt'
apply plugin: 'kotlinx-serialization'
android {
compileSdkVersion 28
defaultConfig {
applicationId "com.example.project"
minSdkVersion 19
targetSdkVersion 28
versionCode 1
versionName "1.0"
testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
vectorDrawables.useSupportLibrary = true
multiDexEnabled true
kapt {
arguments {
arg("room.schemaLocation", "$projectDir/schemas".toString())
}
}
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
flavorDimensions 'version'
productFlavors {
live {
dimension 'version'
}
dev {
dimension 'version'
versionNameSuffix '-dev'
}
}
buildToolsVersion "$rootProject.buildToolsVersion"
compileOptions {
sourceCompatibility JavaVersion.VERSION_1_8
targetCompatibility JavaVersion.VERSION_1_8
}
dataBinding {
enabled = true
}
}
kotlin {
experimental {
coroutines 'enable'
}
}
dependencies {
implementation "com.android.support:multidex:1.0.3"
implementation fileTree(include: ['*.jar'], dir: 'libs')
implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlin_version"
implementation "org.jetbrains.kotlin:kotlin-reflect:$kotlin_version"
implementation "org.jetbrains.kotlinx:kotlinx-serialization-runtime:$serialization_version"
// Support and google services
implementation "com.android.support:support-compat:$rootProject.supportLibVersion"
implementation "com.android.support:support-core-utils:$rootProject.supportLibVersion"
implementation "com.android.support:support-core-ui:$rootProject.supportLibVersion"
implementation "com.android.support:support-media-compat:$rootProject.supportLibVersion"
implementation "com.android.support:support-fragment:$rootProject.supportLibVersion"
implementation "com.android.support:design:$rootProject.supportLibVersion"
implementation "com.android.support:appcompat-v7:$rootProject.supportLibVersion"
implementation "com.android.support:gridlayout-v7:$rootProject.supportLibVersion"
implementation "com.android.support:preference-v7:$rootProject.supportLibVersion"
implementation "com.android.support.constraint:constraint-layout:1.1.3"
implementation "com.android.support:support-annotations:$rootProject.supportLibVersion"
implementation "com.android.support:support-vector-drawable:$rootProject.supportLibVersion"
implementation "com.android.support:recyclerview-v7:$rootProject.supportLibVersion"
implementation "com.google.android.gms:play-services-plus:15.0.1"
// Rx
implementation "io.reactivex.rxjava2:rxandroid:2.1.0"
implementation "io.reactivex.rxjava2:rxjava:2.2.2"
// Retrofit
implementation "com.google.code.gson:gson:2.8.5"
implementation "com.squareup.retrofit2:retrofit:2.4.0"
implementation "com.squareup.retrofit2:converter-gson:2.4.0"
implementation "com.squareup.retrofit2:adapter-rxjava2:2.4.0"
implementation "com.squareup.okhttp3:logging-interceptor:3.11.0"
// Testing
testImplementation "junit:junit:4.12"
androidTestImplementation "com.android.support.test:runner:1.0.2"
androidTestImplementation "com.android.support.test.espresso:espresso-core:3.0.2"
///---
// java 8
implementation "android.arch.lifecycle:common-java8:$archLifecycleVersion"
// Room components
implementation "android.arch.persistence.room:runtime:$rootProject.roomVersion"
annotationProcessor "android.arch.persistence.room:compiler:$rootProject.roomVersion"
androidTestImplementation "android.arch.persistence.room:testing:$rootProject.roomVersion"
kapt "android.arch.persistence.room:compiler:$rootProject.roomVersion"
// Lifecycle components
implementation "android.arch.lifecycle:extensions:$rootProject.archLifecycleVersion"
kapt "android.arch.lifecycle:compiler:$rootProject.archLifecycleVersion"
annotationProcessor "android.arch.lifecycle:compiler:$rootProject.archLifecycleVersion"
}
答案 0 :(得分:21)
我有同样的问题。它与新的AndroidX库及其上的迁移有关。
尝试文件->打开->然后单击build.gradle重新打开项目。
答案 1 :(得分:2)
请从应用目录中删除.idea和.gradle项目,然后使Invalidate和Cache重新启动Android Studio。 这样可以解决此问题。
答案 2 :(得分:0)
我同意Stanislav Mukhametshin的观点,这可能与新的AndroidX库及其上的迁移有关。我已经清理并重建了项目,但是没有用。因此,我尝试了这种方法,错误消失了。
1)转到File
并关闭项目。
2)重新打开同一项目。
答案 3 :(得分:0)
简单的解决方案是:
1:转到文件并关闭项目。
2:然后转到文件并单击“最近打开”并打开您的项目。
那招对我有用。