NullPointerException：尝试从字段 'int android.view.View.mViewFlags' 读取

Question

我的应用程序运行良好，然后我将支持设计库包含在 build.gradle

compile 'com.android.support:design:23.2.1'

Android Studio 提示下载更多组件，之后我开始在导航 b/w 不同片段

时看到太多此类崩溃

FATAL EXCEPTION: main
Process: com.presdo.match.matchtemplate, PID: 23339
java.lang.NullPointerException: Attempt to read from field 'int android.view.View.mViewFlags' on a null object reference
    at android.view.ViewGroup.dispatchDraw(ViewGroup.java:3197)
    at android.view.View.draw(View.java:15234)
    at android.widget.FrameLayout.draw(FrameLayout.java:598)
    at android.view.View.updateDisplayListIfDirty(View.java:14167)
    at android.view.View.getDisplayList(View.java:14189)
    at android.view.ViewGroup.recreateChildDisplayList(ViewGroup.java:3389)
    at android.view.ViewGroup.dispatchGetDisplayList(ViewGroup.java:3368)
    at android.view.View.updateDisplayListIfDirty(View.java:14127)
    at android.view.View.getDisplayList(View.java:14189)
    at android.view.ViewGroup.recreateChildDisplayList(ViewGroup.java:3389)
    at android.view.ViewGroup.dispatchGetDisplayList(ViewGroup.java:3368)
    at android.view.View.updateDisplayListIfDirty(View.java:14127)
    at android.view.View.getDisplayList(View.java:14189)
    at android.view.ViewGroup.recreateChildDisplayList(ViewGroup.java:3389)
    at android.view.ViewGroup.dispatchGetDisplayList(ViewGroup.java:3368)
    at android.view.View.updateDisplayListIfDirty(View.java:14127)
    at android.view.View.getDisplayList(View.java:14189)
    at android.view.ViewGroup.recreateChildDisplayList(ViewGroup.java:3389)
    at android.view.ViewGroup.dispatchGetDisplayList(ViewGroup.java:3368)
    at android.view.View.updateDisplayListIfDirty(View.java:14127)
    at android.view.View.getDisplayList(View.java:14189)
    at android.view.ViewGroup.recreateChildDisplayList(ViewGroup.java:3389)
    at android.view.ViewGroup.dispatchGetDisplayList(ViewGroup.java:3368)
    at android.view.View.updateDisplayListIfDirty(View.java:14127)
    at android.view.View.getDisplayList(View.java:14189)
    at android.view.ViewGroup.recreateChildDisplayList(ViewGroup.java:3389)
    at android.view.ViewGroup.dispatchGetDisplayList(ViewGroup.java:3368)
    at android.view.View.updateDisplayListIfDirty(View.java:14127)
    at android.view.View.getDisplayList(View.java:14189)
    at android.view.ViewGroup.recreateChildDisplayList(ViewGroup.java:3389)
    at android.view.ViewGroup.dispatchGetDisplayList(ViewGroup.java:3368)
    at android.view.View.updateDisplayListIfDirty(View.java:14127)
    at android.view.View.getDisplayList(View.java:14189)
    at android.view.ThreadedRenderer.updateViewTreeDisplayList(ThreadedRenderer.java:273)
    at android.view.ThreadedRenderer.updateRootDisplayList(ThreadedRenderer.java:279)
    at android.view.ThreadedRenderer.draw(ThreadedRenderer.java:318)
    at android.view.ViewRootImpl.draw(ViewRootImpl.java:2530)
    at android.view.ViewRootImpl.performDraw(ViewRootImpl.java:2352)
    at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1982)
    at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1061)
    at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:5885)
    at android.view.Choreographer$CallbackRecord.run(Choreographer.java:767)
    at android.view.Choreographer.doCallbacks(Choreographer.java:580)
    at android.view.Choreographer.doFrame(Choreographer.java:550)
    at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:753)
    at android.os.Handler.handleCallback(Handler.java:739)
    at android.os.Handler.dispatchMessage(Handler.java:95)
    at android.os.Looper.loop(Looper.java:135)
    at android.app.ActivityThread.main(ActivityThread.java:5254)
    at java.lang.reflect.Method.invoke(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:372)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)

这是我的build.gradle

compile 'com.android.support:appcompat-v7:23.2.1'
compile 'com.android.support:recyclerview-v7:+'
compile 'com.android.support:cardview-v7:23.+'
compile 'com.android.support:support-v4:23.0.0'
compile 'com.android.support:percent:23.1.1'
compile 'com.android.support:multidex:1.0.0'
compile 'com.android.support:palette-v7:23.1.0'

我已经看过 this 但我不确定它是否与我的代码有关。

现在，即使我删除 google 设计支持库，我也会看到崩溃，但无法预测它们何时发生，因为在堆栈跟踪中没有对我的项目代码库的引用。

感谢任何帮助。

更新

我对 Gradle 进行了更改以使支持库版本保持一致，而且我再也看不到崩溃了。这是一个片段

ext {
    supportLibVersion = '23.2.1'
}

dependencies {
    compile "com.android.support:appcompat-v7:${supportLibVersion}"
    compile "com.android.support:recyclerview-v7:${supportLibVersion}"
    compile "com.android.support:cardview-v7:${supportLibVersion}"
    compile "com.android.support:support-v4:${supportLibVersion}"
    compile "com.android.support:percent:${supportLibVersion}"
    compile "com.android.support:palette-v7:${supportLibVersion}"
    compile "com.android.support:design:${supportLibVersion}"
    ...
}

Answer 1

混合来自不同支持库的版本通常不是一个好主意，因为它们具有可能无法跨版本工作的相互依赖性。

我会尝试将它们全部更新到 23.2.1，而不是混合使用 23.0、23.1 和 23.2

Answer 2

这是（再次）动画问题。您可能使用

设置了一些自定义动画

fragmentTransaction.setCustomAnimations();

删除它们，它又可以工作了。恭喜，您现在拥有与 5 年前一样的片段转换。

编辑：更好的方法是通过下载

来恢复您的旧存储库

http://dl.google.com/android/repository/android_m2repository_r26.zip

并替换

中的所有内容

/Users/.../Library/Android/sdk/extras/android/m2repository

取自 here。

NullPointerException：尝试从字段 'int android.view.View.mViewFlags' 读取

NullPointerException: Attempt to read from field 'int android.view.View.mViewFlags'

android

nullpointerexception

viewgroup