这个问题我和同事3台电脑都会出现，应该不是个别情况，但是 Google 看起来并没有发现这个严重的问题，可能 Databinding 的使用者比较少吧。

环境

• Android studio 3.1 和 3.2 版本

• Gradle 4.4

• gradlePlugin 3.1.x - 3.2.x

• model 依赖:

   android {
       compileSdkVersion 27
       buildToolsVersion "27.0.3"
       defaultConfig {
           applicationId "com.xxj.mvvm.demo.android_mvvm_demo"
           minSdkVersion 22
           targetSdkVersion 27
           versionCode 1
           versionName "1.0"
           testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
       }
       buildTypes {
           release {
               minifyEnabled false
               proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
           }
       }
       dataBinding {
           enabled = true
       }
   }
  

操作步骤

1. 把 activity_main.xml 转换为 Databinding 布局
2. 在 Activity 中使用 DataBindingUtil 实例化，这时没有问题，代码提示正常，Ctrl 点击 ActivityMainBinding 可成功导航到 xml 文件

   ActivityMainBinding binding = DataBindingUtil.setContentView(this, R.layout.activity_main);
   

3. 然后 make/build project（工具栏小锤子）
4. 发现 ActivityMainBinding 没有代码提示，也无法导航到 xml 布局，studio右下角有报错。

错误信息如下：

    Element: class com.intellij.psi.impl.source.xml.XmlFileImpl because: different providers: SingleRootFileViewProvider{myVirtualFile=file://C:/Users/52492/AndroidStudioProjects/MyOpenProject/Android-MVVM-Demo/app/src/main/res/layout/activity_main2.xml, content=VirtualFileContent{size=1789}}(1b3cefd9); SingleRootFileViewProvider{myVirtualFile=file://C:/Users/52492/AndroidStudioProjects/MyOpenProject/Android-MVVM-Demo/app/src/main/res/layout/activity_main2.xml, content=VirtualFileContent{size=1789}}(3501664b)
        invalidated at: see attachment
        com.intellij.psi.PsiInvalidElementAccessException: Element: class com.intellij.psi.impl.source.xml.XmlFileImpl because: different providers: SingleRootFileViewProvider{myVirtualFile=file://C:/Users/52492/AndroidStudioProjects/MyOpenProject/Android-MVVM-Demo/app/src/main/res/layout/activity_main2.xml, content=VirtualFileContent{size=1789}}(1b3cefd9); SingleRootFileViewProvider{myVirtualFile=file://C:/Users/52492/AndroidStudioProjects/MyOpenProject/Android-MVVM-Demo/app/src/main/res/layout/activity_main2.xml, content=VirtualFileContent{size=1789}}(3501664b)
            invalidated at: see attachment
            at com.intellij.psi.util.PsiUtilCore.ensureValid(PsiUtilCore.java:502)
            at com.intellij.psi.impl.smartPointers.SmartPointerManagerImpl.createSmartPsiElementPointer(SmartPointerManagerImpl.java:78)
            at com.intellij.psi.impl.smartPointers.SmartPointerManagerImpl.createSmartPsiElementPointer(SmartPointerManagerImpl.java:69)
            at com.intellij.psi.impl.smartPointers.SmartPointerManagerImpl.createSmartPsiElementPointer(SmartPointerManagerImpl.java:64)
            at com.intellij.codeInsight.completion.JavaPsiClassReferenceElement.<init>(JavaPsiClassReferenceElement.java:49)
            at com.intellij.codeInsight.completion.AllClassesGetter.createLookupItem(AllClassesGetter.java:170)
            at com.intellij.codeInsight.completion.JavaClassNameCompletionContributor.createClassLookupItems(JavaClassNameCompletionContributor.java:237)
            at com.intellij.codeInsight.completion.JavaCompletionUtil.createLookupElements(JavaCompletionUtil.java:521)
            at com.intellij.codeInsight.completion.JavaCompletionUtil.processJavaQualifiedReference(JavaCompletionUtil.java:310)
            at com.intellij.codeInsight.completion.JavaCompletionUtil.processJavaReference(JavaCompletionUtil.java:277)
            at com.intellij.codeInsight.completion.JavaCompletionContributor.lambda$addReferenceVariants$7(JavaCompletionContributor.java:451)
            at com.intellij.codeInsight.completion.LegacyCompletionContributor.processReference(LegacyCompletionContributor.java:125)
            at com.intellij.codeInsight.completion.LegacyCompletionContributor.processReferences(LegacyCompletionContributor.java:108)
            at com.intellij.codeInsight.completion.JavaCompletionContributor.addReferenceVariants(JavaCompletionContributor.java:437)
            at com.intellij.codeInsight.completion.JavaCompletionContributor.fillCompletionVariants(JavaCompletionContributor.java:263)
            at com.intellij.codeInsight.completion.CompletionService.getVariantsFromContributors(CompletionService.java:83)
            at com.intellij.codeInsight.completion.CompletionResultSet.runRemainingContributors(CompletionResultSet.java:149)
            at com.intellij.codeInsight.completion.CompletionResultSet.runRemainingContributors(CompletionResultSet.java:142)
            at com.intellij.codeInsight.completion.JavaNoVariantsDelegator.fillCompletionVariants(JavaNoVariantsDelegator.java:61)
            at com.intellij.codeInsight.completion.CompletionService.getVariantsFromContributors(CompletionService.java:83)
            at com.intellij.codeInsight.completion.CompletionResultSet.runRemainingContributors(CompletionResultSet.java:149)
            at com.intellij.codeInsight.completion.CompletionResultSet.runRemainingContributors(CompletionResultSet.java:142)
            at com.intellij.codeInsight.completion.JShellCompletionContributor.fillCompletionVariants(JShellCompletionContributor.java:28)
            at com.intellij.codeInsight.completion.CompletionService.getVariantsFromContributors(CompletionService.java:83)
            at com.intellij.codeInsight.completion.CompletionResultSet.runRemainingContributors(CompletionResultSet.java:149)
            at com.intellij.codeInsight.completion.CompletionResultSet.runRemainingContributors(CompletionResultSet.java:142)
            at com.intellij.codeInsight.template.impl.LiveTemplateCompletionContributor$2.addCompletions(LiveTemplateCompletionContributor.java:90)
            at com.intellij.codeInsight.completion.CompletionProvider.addCompletionVariants(CompletionProvider.java:36)
            at com.intellij.codeInsight.completion.CompletionContributor.fillCompletionVariants(CompletionContributor.java:152)
            at com.intellij.codeInsight.completion.CompletionService.getVariantsFromContributors(CompletionService.java:83)
            at com.intellij.codeInsight.completion.CompletionService.performCompletion(CompletionService.java:112)
            at com.intellij.codeInsight.completion.CompletionProgressIndicator.calculateItems(CompletionProgressIndicator.java:839)
            at com.intellij.codeInsight.completion.CompletionProgressIndicator.access$600(CompletionProgressIndicator.java:92)
            at com.intellij.codeInsight.completion.CompletionProgressIndicator$1CalculateItems.run(CompletionProgressIndicator.java:821)
            at com.intellij.openapi.application.impl.ApplicationImpl.tryRunReadAction(ApplicationImpl.java:1130)
            at com.intellij.codeInsight.completion.AsyncCompletion.tryReadOrCancel(CompletionThreading.java:181)
            at com.intellij.codeInsight.completion.CompletionProgressIndicator.lambda$startCompletion$6(CompletionProgressIndicator.java:832)
            at com.intellij.codeInsight.completion.AsyncCompletion.lambda$null$0(CompletionThreading.java:108)
            at com.intellij.openapi.progress.impl.CoreProgressManager.lambda$runProcess$1(CoreProgressManager.java:157)
            at com.intellij.openapi.progress.impl.CoreProgressManager.registerIndicatorAndRun(CoreProgressManager.java:543)
            at com.intellij.openapi.progress.impl.CoreProgressManager.executeProcessUnderProgress(CoreProgressManager.java:488)
            at com.intellij.openapi.progress.impl.ProgressManagerImpl.executeProcessUnderProgress(ProgressManagerImpl.java:94)
            at com.intellij.openapi.progress.impl.CoreProgressManager.runProcess(CoreProgressManager.java:144)
            at com.intellij.codeInsight.completion.AsyncCompletion.lambda$startThread$1(CompletionThreading.java:104)
            at com.intellij.openapi.application.impl.ApplicationImpl$1.run(ApplicationImpl.java:315)
            at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
            at java.util.concurrent.FutureTask.run(FutureTask.java:266)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
            at java.lang.Thread.run(Thread.java:745)

这个错误困扰了我半年多了没法解决（自己菜），然后到 IDEA 社区找到了这个

Strange behaviour after update to 2017.3 when editing primefaces xhtml files

我看见这位大哥和我报错的关键字相同，我就看了一下，发现最初的 studio 3.1 版本就是基于 IDEA 2017.3 的（studio 3.0 基于 2017.1），所以我在项目中同时使用 config.gradle 和 Databinding 在 studio 3.0 运行正常，在 3.1 3.2 版本直接爆炸。

嗯，然后我就把这个 bug 归结为 IDEA 的更新导致 studio 上出了这个问题，社区中说这个 bug 已经在后面版本中解决，然而 studio 的高级版本还是没法使用。

最后

困扰多时的问题终于在 studio 3.3 版本解决了，但是现在 3.3 版本还是预览版，想使用 Databinding 的同学可以去下载

• Android Studio 3.3 预览版
• Android Studio 3.0.1 正式版