FixedHeightScrollingViewBehavior.java

package com.evs.demo.layout;

import android.content.Context;
import android.content.res.TypedArray;
import android.support.design.widget.AppBarLayout;
import android.support.design.widget.CoordinatorLayout;
import android.support.v4.view.ViewCompat;
import android.util.AttributeSet;
import android.view.View;

import java.util.List;

public class FixedScrollingViewBehavior extends AppBarLayout.ScrollingViewBehavior{

    public FixedScrollingViewBehavior() {
    }

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

    public boolean onMeasureChild(CoordinatorLayout parent, View child, int parentWidthMeasureSpec, int widthUsed, int parentHeightMeasureSpec, int heightUsed) {
        if(child.getLayoutParams().height == -1) {
            List dependencies = parent.getDependencies(child);
            if(dependencies.isEmpty()) {
                return false;
            }

            AppBarLayout appBar = findFirstAppBarLayout(dependencies);
            if(appBar != null && ViewCompat.isLaidOut(appBar)) {
                if(ViewCompat.getFitsSystemWindows(appBar)) {
                    ViewCompat.setFitsSystemWindows(child, true);
                }

                int scrollRange = appBar.getTotalScrollRange();
                int height = parent.getHeight() - appBar.getMeasuredHeight() + Math.min(scrollRange,  parent.getHeight()- heightUsed);
                int heightMeasureSpec = View.MeasureSpec.makeMeasureSpec(height, View.MeasureSpec.EXACTLY);
                parent.onMeasureChild(child, parentWidthMeasureSpec, widthUsed, heightMeasureSpec, heightUsed);
                return true;
            }
        }

        return false;
    }

    private static AppBarLayout findFirstAppBarLayout(List<View> views) {
        int i = 0;

        for(int z = views.size(); i < z; ++i) {
            View view = (View)views.get(i);
            if(view instanceof AppBarLayout) {
                return (AppBarLayout)view;
            }
        }

        return null;
    }
}

layout.xml

    <android.support.v4.widget.NestedScrollView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_behavior="com.evs.demo.layout.FixedScrollingViewBehavior">
        
     .....   
    </android.support.v4.widget.NestedScrollView>

To watch the result : https://www.youtube.com/watch?v=B0BCZNmFgWg

Hi, nice fix. However, when the scroll content is smaller than the scroll itself, the scroll still responds and collapses the toolbar. Any idea how to just disable the scroll and the collapse when the scroll is not needed at all (for small content scenarios)

Hi, I haven't tried this yet but I guess you should be able to do it by overriding the behavior on the AppBarLayout (android.support.design.widget.AppBarLayout.ScrollingViewBehavior).

I worked with the NestedScrollView for almost 3 hours without a solution, this class saved my life! Thanks a lot

nice job! thanks

thanks a lot!

how this will work in this layout ? i want a xml like : RelativeLayout + Linearlayout + Design Tab Layout + viewpager (Now ViewPager contains Fragment for each Tab ? ) but now i want once i try to scroll any tabLayout (Fragment) it should scroll from top or with top means tab will also move

I worked on this problem for hours.

Thank you ! 👍

Thank you!!

I am unable to use it. Please help me for this

very nice, tks!!