Question

例外情况如下：

java.lang.NullPointerException: Attempt to read from field 'java.lang.Runnable android.databinding.ViewDataBinding.mRebindRunnable' on a null object reference
        at android.databinding.ViewDataBinding.access$100(ViewDataBinding.java:51)
        at android.databinding.ViewDataBinding$5.onViewAttachedToWindow(ViewDataBinding.java:142)
        at android.view.View.dispatchAttachedToWindow(View.java:14525)
        at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:2836)
        at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:2843)
        at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:2843)
        at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:2843)
        at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:2843)
        at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:2843)
        at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:2843)
        at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:2843)
        at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1364)
        at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1107)
        at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6013)
        at android.view.Choreographer$CallbackRecord.run(Choreographer.java:858)
        at android.view.Choreographer.doCallbacks(Choreographer.java:670)
        at android.view.Choreographer.doFrame(Choreographer.java:606)
        at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:844)
        at android.os.Handler.handleCallback(Handler.java:739)
        at android.os.Handler.dispatchMessage(Handler.java:95)
        at android.os.Looper.loop(Looper.java:148)
        at android.app.ActivityThread.main(ActivityThread.java:5417)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)

让我尽力使描述简洁明了。

首先，这与动态添加的布局有关。活动的数据绑定完美无误地运行。这是布局foo_view：

<layout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools">
    <data>
        <variable
            name="foo"
            type="net.mydomain.myapp.MyActivity.Foo" />
        <import type="android.view.View" />
    </data>
    <!--For the sake of debugging, no data binding is actually used-->
    ...
</layout>

在MyActivity.java中：

public class MyActivity extends AppCompatActivity {
    public class Foo{
       ...
    }


   ...
   addFoo(){
       FooViewBinding binding = DataBindingUtil.inflate(LayoutInflater.from(this), R.layout.foo_view, myGridLayout, true); 
       Foo foo = new Foo();
       binding.setFoo(foo);  
   }
}

应用程序在MyActivity启动后立即兑现。崩溃不是由特定的代码行引起的。

有人可以对此有所了解吗？

[编辑] 2016-06-30

崩溃发生在棒棒糖上，但相同的代码在果冻豆上运行良好

Answer 1

如果有人遇到同样的问题，当您更改启用数据绑定的视图的标记（即view.setTag(object)）时会发生此错误，因为数据绑定库会为自身使用标记。

Answer 2

就我而言，

如果我在“合并”中使用，它会在某些屏幕上出现错误。

<merge tools:parentTag="androidx.constraintlayout.widget.ConstraintLayout">

        <androidx.constraintlayout.widget.Group
            android:id="@+id/constraint_group_active"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:visibility="@{data != null}"
            app:constraint_referenced_ids="txt_offering_slogan,view_extra_gift,iv_offering,txt_offering_title,txt_offering_subtitle,txt_buy_extra_gift"
            tools:visibility="visible" />
</merge>

由与java.lang.Runnable相关的数据绑定引起的应用程序崩溃android.databinding.ViewDataBinding.mRebindRunnable

2 个答案: