java.lang.NullPointerException: Attempt to invoke virtual method 'int android.view.ViewGroup.indexOfChild(android.view.View)' on a null object

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via GitHub by MahdiPishguy
, 1 year ago
Attempt to invoke virtual method 'int android.view.ViewGroup.indexOfChild(android.view.View)' on a null object
java.lang.NullPointerException: Attempt to invoke virtual method 'int android.view.ViewGroup.indexOfChild(android.view.View)' on a null object
at com.alexvasilkov.foldablelayout.UnfoldableView.switchViews(UnfoldableView.java:384)
at com.alexvasilkov.foldablelayout.UnfoldableView.clearCoverViewInternal(UnfoldableView.java:368)
at com.alexvasilkov.foldablelayout.UnfoldableView.onFoldedBack(UnfoldableView.java:150)
at com.alexvasilkov.foldablelayout.UnfoldableView.setState(UnfoldableView.java:186)
at com.alexvasilkov.foldablelayout.UnfoldableView.setFoldRotation(UnfoldableView.java:254)
at com.alexvasilkov.foldablelayout.FoldableListLayout.setFoldRotation(FoldableListLayout.java:251)
at android.animation.PropertyValuesHolder.nCallFloatMethod(Native Method)
at android.animation.PropertyValuesHolder.access$400(PropertyValuesHolder.java:37)
at android.animation.PropertyValuesHolder$FloatPropertyValuesHolder.setAnimatedValue(PropertyValuesHolder.java:1296)
at android.animation.ObjectAnimator.animateValue(ObjectAnimator.java:981)
at android.animation.ValueAnimator.animationFrame(ValueAnimator.java:1384)
at android.animation.ValueAnimator.doAnimationFrame(ValueAnimator.java:1427)
at android.animation.ValueAnimator$AnimationHandler.doAnimationFrame(ValueAnimator.java:759)
at android.animation.ValueAnimator$AnimationHandler$1.run(ValueAnimator.java:801)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:858)
at android.view.Choreographer.doCallbacks(Choreographer.java:670)
at android.view.Choreographer.doFrame(Choreographer.java:603)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:844)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:234)
at android.app.ActivityThread.main(ActivityThread.java:5526)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)

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