获取NullPointerException：尝试从字段“ int android.view.View.mViewFlags”读取-Android动画 [英] getting NullPointerException: Attempt to read from field 'int android.view.View.mViewFlags' - Android animation
问题描述
我实现了一个动画，在回收者视图中有imageview，单击该项目后我想在回收者视图之外的图像视图上做一些动画，这样
-我创建了一个新的imageview
-将其添加到主容器中
-对其进行动画处理
-最后我将其从主容器中删除
I have implemented an animation where i have imageview in recycler view, on clicking the item i want to do some animation on the image view outside the recycler view, so that - I created a new imageview, - added it to the main container - did the animation on it - lastly I remove it from the main container
这里是回收者视图中单击项的代码：
Here is the code for the on click item of the recycler view:
代码：
final ImageView iv = new ImageView(getContext());
iv.setImageDrawable(fromView.getDrawable());
iv.setScaleType(ImageView.ScaleType.CENTER_INSIDE);
iv.setLayoutParams(fromView.getLayoutParams());
v_mainContainer.addView(iv);
AnimationSet animatinSet = new AnimationSet(false);
animatinSet.setFillAfter(false);
animatinSet.setFillBefore(true);
animatinSet.setDuration(1500);
animatinSet.setInterpolator(new DecelerateInterpolator());
// ... rest of the animation
animatinSet.setAnimationListener(new Animation.AnimationListener() {
@Override
public void onAnimationStart(Animation animation) {
}
@Override
public void onAnimationEnd(Animation animation) {
v_mainContainer.removeView(iv);
}
@Override
public void onAnimationRepeat(Animation animation) {
}
});
animatinSet.setAnimationListener(animationListner);
animatinSet.setDuration(1500);
iv.startAnimation(animatinSet);
在1个视图上运行此动画时，它可以正常工作。但是，当我在同一视图上多次运行动画时，以及在一个视图在我运行另一个视图之前未完成时，都会出现以下错误。
When I run this animation on 1 view, It works correctly. However, I get the error below when I run the animation many times on same view, and before one finishes when I run the another.
错误日志：
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.mbh.testApp, PID: 9628
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:3549)
at android.view.View.draw(View.java:17071)
at android.view.View.updateDisplayListIfDirty(View.java:16050)
at android.view.ViewGroup.recreateChildDisplayList(ViewGroup.java:3748)
at android.view.ViewGroup.dispatchGetDisplayList(ViewGroup.java:3728)
at android.view.View.updateDisplayListIfDirty(View.java:16013)
at android.view.ViewGroup.recreateChildDisplayList(ViewGroup.java:3748)
at android.view.ViewGroup.dispatchGetDisplayList(ViewGroup.java:3728)
at android.view.View.updateDisplayListIfDirty(View.java:16013)
at android.view.ViewGroup.recreateChildDisplayList(ViewGroup.java:3748)
at android.view.ViewGroup.dispatchGetDisplayList(ViewGroup.java:3728)
at android.view.View.updateDisplayListIfDirty(View.java:16013)
at android.view.ViewGroup.recreateChildDisplayList(ViewGroup.java:3748)
at android.view.ViewGroup.dispatchGetDisplayList(ViewGroup.java:3728)
at android.view.View.updateDisplayListIfDirty(View.java:16013)
at android.view.ViewGroup.recreateChildDisplayList(ViewGroup.java:3748)
at android.view.ViewGroup.dispatchGetDisplayList(ViewGroup.java:3728)
at android.view.View.updateDisplayListIfDirty(View.java:16013)
at android.view.ThreadedRenderer.updateViewTreeDisplayList(ThreadedRenderer.java:656)
at android.view.ThreadedRenderer.updateRootDisplayList(ThreadedRenderer.java:662)
at android.view.ThreadedRenderer.draw(ThreadedRenderer.java:770)
at android.view.ViewRootImpl.draw(ViewRootImpl.java:2796)
at android.view.ViewRootImpl.performDraw(ViewRootImpl.java:2604)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:2211)
at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1246)
at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6301)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:871)
at android.view.Choreographer.doCallbacks(Choreographer.java:683)
at android.view.Choreographer.doFrame(Choreographer.java:619)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:857)
at android.os.Handler.handleCallback(Handler.java:751)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6077)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:865)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:755)
从主容器中删除视图时，我尝试放置try-catch块，但没有更改结果，仍然出现相同的错误。
I tried to put try-catch block when removing the view from the main container, but it did not change the result and still getting the same error.
我也尝试了此答案 https://stackoverflow.com/a/4295570/2296787 并没有解决问题
I tried also this answer https://stackoverflow.com/a/4295570/2296787 and it did not solve the problem
奇怪的是该错误并没有显示出我在哪里
The strange is that the error doesnt show me where exactly the exception raises.
在此先感谢您的帮助。
推荐答案
如 @sasikumar 所述，解决方案是在真实数据中心上运行测试
As @sasikumar has mentioned the solution was to run the test on real device
但是我也在模拟器上解决了这个问题，方法是在动画结束侦听器中删除视图之前，添加500毫秒延迟的postDelayed：
but also i solved it on the emulator also by adding postDelayed with 500 milliseconds delay before removing the view in the animation end listener:
animatinSet.setAnimationListener(new Animation.AnimationListener() {
@Override
public void onAnimationStart(Animation animation) {
}
@Override
public void onAnimationEnd(Animation animation) {
iv.setVisibility(View.GONE);
v_mainContainer.postDelayed(new Runnable() {
@Override
public void run() {
v_mainContainer.removeView(iv);
}
}, 500);
}
@Override
public void onAnimationRepeat(Animation animation) {
}
});
这对模拟器和真实设备都有效
This works for both Emulator and Real Devices
这篇关于获取NullPointerException：尝试从字段“ int android.view.View.mViewFlags”读取-Android动画的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
