onClick method not working properly after NestedScrollView scrolled

I've opened another issue here: https://issuetracker.google.com/issues/68103042 as it still seems to be an issue in Oreo for us (multiple devices, including emulators).

My fix (adapted from [email protected]'s suggestions at https://issuetracker.google.com/issues/37051723) doesn't require modifying AOSP code as it uses reflection:

public class MyNestedScrollView extends NestedScrollView {

    private static final Logger sLogger = LogFactory.getLogger(MyNestedScrollView.class);

    private OverScroller mScroller;
    public boolean isFling = false;

    public MyNestedScrollView(Context context, AttributeSet attrs) {
        super(context, attrs);
        mScroller = getOverScroller();
    }

    @Override
    public void fling(int velocityY) {
        super.fling(velocityY);

        // here we effectively extend the super class functionality for backwards compatibility and just call invalidateOnAnimation()
        if (getChildCount() > 0) {
            ViewCompat.postInvalidateOnAnimation(this);

            // Initializing isFling to true to track fling action in onScrollChanged() method
            isFling = true;
        }
    }

    @Override
    protected void onScrollChanged(int l, final int t, final int oldl, int oldt) {
        super.onScrollChanged(l, t, oldl, oldt);

        if (isFling) {
            if (Math.abs(t - oldt) <= 3 || t == 0 || t == (getChildAt(0).getMeasuredHeight() - getMeasuredHeight())) {
                isFling = false;

                // This forces the mFinish variable in scroller to true (as explained the
                //    mentioned link above) and does the trick
                if (mScroller != null) {
                    mScroller.abortAnimation();
                }
            }
        }
    }

    private OverScroller getOverScroller() {
        Field fs = null;
        try {
            fs = this.getClass().getSuperclass().getDeclaredField("mScroller");
            fs.setAccessible(true);
            return (OverScroller) fs.get(this);
        } catch (Throwable t) {
            return null;
        }
    }
}

It is a Bug mention at Google #issues 194398.

Just need to use this WorkaroundNestedScrollView.java class which extends NestedScrollView like,

WorkaroundNestedScrollView.java

public class WorkaroundNestedScrollView extends NestedScrollView {

public WorkaroundNestedScrollView(Context context, AttributeSet attrs) {
    super(context, attrs);
}

@Override
public boolean onInterceptTouchEvent(MotionEvent ev) {
    if (ev.getAction() == MotionEvent.ACTION_DOWN) {
        // Explicitly call computeScroll() to make the Scroller compute itself
        computeScroll();
    }
    return super.onInterceptTouchEvent(ev);
}
}

And in yourlayout use it like this,

layout.xml

<com.yourpackagename.whatever.WorkaroundNestedScrollView
    android:layout_width="match_parent"
    android:layout_height="match_parent">
...
...

</com.yourpackagename.whatever.WorkaroundNestedScrollView>

You can alson find more details here.

I found solution for same problem on this thread :The item inside RecyclerView can't be clicked right after scrolling

You can fix your code by adding layout_behavior to your AppBarLayout.You can find code here Fixed AppBarLayout.Behavior .Just add this class tou your project and fix your code :

<android.support.design.widget.AppBarLayout android:layout_width="match_parent" app:layout_behavior="yourPackageName.FixAppBarLayoutBehavior" android:layout_height="wrap_content">

It is a bug of the NestedScrollView, the detail of the bug can be found in here: issue. The problem is that mScroller.isFinished() in onInterceptTouchEvent(MotionEvent ev) will not return true after a fling operation (even if the fling is stopped). Therefore the touch event is intercepted.

This bug have been reported for a while, but still have not been fixed. So I have created by own version of bug fix for this problem. I implemented my own NestedScrollView, copied all the code from NestedScrollView and having the with the following amendments:

public class NestedScrollView extends FrameLayout implements NestedScrollingParent, NestedScrollingChild {
    ...
    private void initScrollView() {
        ...
        // replace this line:
        // mScroller = new ScrollerCompat(getContext(), null);
        mScroller = ScrollerCompat.create(getContext(), null);
        ...
    }

    @Override
    public boolean onInterceptTouchEvent(MotionEvent ev) {
        ...
        switch (action & MotionEventCompat.ACTION_MASK) {
            ...
            case MotionEvent.ACTION_DOWN: {
                ...
                // replace this line:
                // mIsBeingDragged = !mScroller.isFinished();
                mIsBeingDragged = false;
                ...
            }
        }
    }   
}

And this NestedScrollView should have the same behaviour as the original one.