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

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?

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

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);
}
}

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;
}
}

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);

How do I make RecyclerView grid "full height"?

Before RecyclerView, I used this class to make grid's height dependant on it's childs(so it works fine in scrollview):
public class FullHeightGridView extends GridView
{
public FullHeightGridView(Context context)
{
super(context);
}
public FullHeightGridView(Context context, AttributeSet attrs)
{
super(context, attrs);
}
public FullHeightGridView(Context context, AttributeSet attrs,
int defStyle)
{
super(context, attrs, defStyle);
}
#Override
public void onMeasure(int widthMeasureSpec, int heightMeasureSpec)
{
// 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();
}
}
How can I modify GridLayoutManager to behave in the same way?

How can I determine the direction of a vertical ScrollView?

How can I determine the direction of a vertical ScrollView?
I need to hide and display another linear layout accoding to scrollview scroll

You can use the onScrollChanged(int l, int t, int oldl, int oldt) method for that. As there isn't a setter for a listener, but just that method, you will have to create your own ScrollView class and override that method and do your thing in your implementation.

public class ObservableScrollView extends ScrollView {
private static final int DEFAULT_THRESHOLD_DP = 4;
private ScrollDirectionListener scrollDirectionListener;
private int scrollThreshold;
public ObservableScrollView(Context context) {
this(context, null);
}
public ObservableScrollView(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}
public ObservableScrollView(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init(context);
}
private void init(Context context) {
scrollThreshold = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, DEFAULT_THRESHOLD_DP, context.getResources().getDisplayMetrics());
}
#Override
protected void onScrollChanged(int x, int y, int oldX, int oldY) {
super.onScrollChanged(x, y, oldX, oldY);
if (Math.abs(y - oldY) > scrollThreshold && scrollDirectionListener != null) {
if (y > oldY) {
scrollDirectionListener.onScrollUp(Math.abs(y - oldY));
} else {
scrollDirectionListener.onScrollDown(Math.abs(y - oldY));
}
}
}
public void setScrollThresholdInPx(int px) {
scrollThreshold = px;
}
public void setScrollThresholdInDp(Context context, float dp) {
scrollThreshold = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dp, context.getResources().getDisplayMetrics());
}
public void setOnScrollDirectionListener(ScrollDirectionListener listener) {
scrollDirectionListener = listener;
}
public interface ScrollDirectionListener {
void onScrollDown(int pixels);
void onScrollUp(int pixels);
}}
got answer :) use this custom scrollview
ScrollView.setOnScrollDirectionListener(new ObservableScrollView.ScrollDirectionListener() {
#Override
public void onScrollDown(int pixels) {
contenttool.setVisibility(View.INVISIBLE);
}
#Override
public void onScrollUp(int pixels) {
contenttool.setVisibility(View.VISIBLE);
}
});

Changing View Height inside a custom ScrollView onScrollChanged

I'm trying to make the following effect:
I have a custom ScrollView (in oder to get the onScrollChanged listener) and a custom View inside it. In the custom View I succeed to place the item as I want.
Here my customView:
public class CustomView extends FrameLayout {
private TextView nameView;
private TextView emailView;
private ImageView addressView;
private Tracks track ;
private double scrollProgress = 0.0;
private double topViewScaleFactor = 2.0;
private double collapsedViewHeight = 200.0;
private double expandedViewHeight = 700.0;
private double scrollProgressPerView = expandedViewHeight;
View v;
View firstItem;
View secondView;
int itemMinHeight = 200;
int itemMaxHeight = 700;
public CustomView(MyScrollView paramEventListView, Context paramContext){
super(paramContext);
}
public CustomView(Context context) {
super(context);
// TODO Auto-generated constructor stub
}
public CustomView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
// TODO Auto-generated constructor stub
}
public CustomView(Context context, AttributeSet attrs) {
super(context, attrs);
// TODO Auto-generated constructor stub
}
#Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
// TODO Auto-generated method stub
int m = getMeasuredWidth();
int itemWidth = (r-l)/getChildCount();
// int itemHeight = (b-t)/getChildCount();
firstItem = getChildAt(0);
//firstItem.layout(0, 0, r-l, itemMaxHeight);
firstItem.measure(View.MeasureSpec.makeMeasureSpec(m, MeasureSpec.EXACTLY), View.MeasureSpec.makeMeasureSpec(itemMaxHeight, MeasureSpec.EXACTLY));
firstItem.layout(0, 0, r-l, itemMaxHeight);
secondView = getChildAt(1);
secondView.measure(View.MeasureSpec.makeMeasureSpec(m, MeasureSpec.EXACTLY), View.MeasureSpec.makeMeasureSpec(itemMinHeight, MeasureSpec.EXACTLY));
secondView.layout(0, itemMaxHeight, r-l, itemMinHeight+itemMaxHeight);
int FirstAndSEcondItemHeight = firstItem.getHeight() + secondView.getHeight();
for(int i=2; i< this.getChildCount(); i++){
v = getChildAt(i);
// v.layout(itemWidth*i, 0, (i+1)*itemWidth, b-t);
v.layout(0, FirstAndSEcondItemHeight + (itemMinHeight*(i-2)), r-l, FirstAndSEcondItemHeight + ((i-1)*itemMinHeight));
}
}
#Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
// TODO Auto-generated method stub
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
int heightMeasured = 0;
/*for each child get height and
heightMeasured += childHeight;*/
for(int i=0; i< this.getChildCount(); i++){
heightMeasured += getChildAt(i).getHeight();
}
//If I am in a scrollview i got heightmeasurespec == 0, so
if(heightMeasureSpec == 0){
heightMeasureSpec = MeasureSpec.makeMeasureSpec(heightMeasured, MeasureSpec.EXACTLY);
}
setMeasuredDimension(getDefaultSize(getSuggestedMinimumWidth(), widthMeasureSpec), getDefaultSize(this.getSuggestedMinimumHeight(), heightMeasureSpec));
}
Here my Custom ScrollView:
public class MyScrollView extends ScrollView{
public MyScrollView(Context context) {
super(context);
}
public MyScrollView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
add(context);
}
public MyScrollView(Context context, AttributeSet attrs) {
super(context, attrs);
}
public void setScrollViewListener(ScrollViewListener scrollViewListener) {
this.scrollViewListener = scrollViewListener;
}
#Override
protected void onScrollChanged(int x, int y, int oldx, int oldy) {
super.onScrollChanged(x, y, oldx, oldy);
// How can I acces to each child in the customView class, and change their height depending on the scrollChanged
}
But now I need to change the item height when I scroll the scrollview. I don't know what to put in the onScrollChanged...
If someone has an idea?
Thanks

Perhaps you want to force the view to redraw by calling invalidate()?
From comment: I think you need to move your code in the onMeasure method to replace the "TODO" stub, so that super.onMeasure() is called after your manipulations. And make sure you're passing the new width/height calculations to it.

How can I catch that View become visible

I inflate Views on ScrollView.
And I need to get event, when on scrolling one of this Views (last, for example, or special type) becomes visible (in screen zone).

If a view changes visibility, the onlayout method is called, you could try overwriting that method and check it's state.

You need to override the view's onVisibilityChanged(). This is also called when one of the view's ancestors changes visibility.

This I inflated my GridView and get what you want
public class MyGrideView extends GridView {
boolean expanded = false;
public MyGrideView(Context context) {
super(context);
}
public MyGrideView(Context context, AttributeSet attrs) {
super(context, attrs);
}
public MyGrideView(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.
// But do not use the highest 2 bits of this integer; those are
// reserved for the MeasureSpec mode.
int expandSpec = MeasureSpec.makeMeasureSpec(
Integer.MAX_VALUE >> 2, 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;
}
}