RecyclerView inside NestedScrollView takes too much time when loading large amount of data

Question

RecyclerView inside NestedScrollView freezes the Activity when loading large amount of data. It loads much faster with ScrollView, but scrolling is affected in that case. I tried setting attributes like setAutoMeasure and setNestedScrollingEnabled which did not help. Any suggestions?

Answer 1

Recycling of views is not supported inside NestedScrollViews as I understand, so the suggestion would be to try to change your layout.

Answer 2

This help to increase the speed of recycler view scrolling.

SpeedyLinearLayoutManager linearLayoutManager = new SpeedyLinearLayoutManager(MainActivity.this);
linearLayoutManager.setOrientation(LinearLayoutManager.VERTICAL);

myRecyclerView.setLayoutManager(linearLayoutManager);

SpeedyLinearLayoutManager.class

 public class SpeedyLinearLayoutManager extends LinearLayoutManager {

        private static final float MILLISECONDS_PER_INCH = 2f; //default is 25f (bigger = slower)

        public SpeedyLinearLayoutManager(Context context) {
            super(context);
        }

        public SpeedyLinearLayoutManager(Context context, int orientation, boolean reverseLayout) {
            super(context, orientation, reverseLayout);
        }

        public SpeedyLinearLayoutManager(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
            super(context, attrs, defStyleAttr, defStyleRes);
        }

        @Override
        public void smoothScrollToPosition(RecyclerView recyclerView, RecyclerView.State state, int position) {

            final LinearSmoothScroller linearSmoothScroller = new LinearSmoothScroller(recyclerView.getContext()) {

                @Override
                public PointF computeScrollVectorForPosition(int targetPosition) {
                    return SpeedyLinearLayoutManager.this.computeScrollVectorForPosition(targetPosition);
                }

                @Override
                protected float calculateSpeedPerPixel(DisplayMetrics displayMetrics) {
                    return MILLISECONDS_PER_INCH / displayMetrics.densityDpi;
                }
            };

            linearSmoothScroller.setTargetPosition(position);
            startSmoothScroll(linearSmoothScroller);
        }
    }

Answer 3

Use Custom list view instead of Recycler view inside scroll view...

Check this Answer

Custom List View

import android.content.Context;
import android.util.AttributeSet;
import android.view.ViewGroup;
import android.widget.ListView;

public class ExpandableHeightListView extends ListView {

boolean expanded = true;
public ExpandableHeightListView(Context context) {
    super(context);
}
public ExpandableHeightListView(Context context, AttributeSet attrs) {
    super(context, attrs);
}
public ExpandableHeightListView(Context context, AttributeSet attrs,
        int defStyle) {
    super(context, attrs, defStyle);
}
public boolean isExpanded() {
    return expanded;
}
@Override
public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    // HACK! TAKE THAT ANDROID!
    if (isExpanded()) {
        // Calculate entire height by providing a very large height hint.
        // View.MEASURED_SIZE_MASK represents the largest height possible.
        int expandSpec = MeasureSpec.makeMeasureSpec(MEASURED_SIZE_MASK,
                MeasureSpec.AT_MOST);
        super.onMeasure(widthMeasureSpec, expandSpec);

        ViewGroup.LayoutParams params = getLayoutParams();
        params.height = getMeasuredHeight();
    } else {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    }
}

public void setExpanded(boolean expanded) {
    this.expanded = expanded;
}
}

Answer 4

you can include app:layout_behavior="@string/appbar_scrolling_view_behavior"

<android.support.v7.widget.RecyclerView
    android:id="@+id/recyclerView"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" />

or disable the nested scrolling behavior for the recycler view.

recyclerView.setNestedScrollingEnabled(false);