Equivalent of ListView.setEmptyView in RecyclerView

Question

In RecyclerView, I want to set an empty view to be shown when the adapter is empty. Is there an equivalent of ListView.setEmptyView()?

Answer 1

Here's a class similar to @dragon born's, but more complete. Based on this gist.

public class EmptyRecyclerView extends RecyclerView {
    private View emptyView;
    final private AdapterDataObserver observer = new AdapterDataObserver() {
        @Override
        public void onChanged() {
            checkIfEmpty();
        }

        @Override
        public void onItemRangeInserted(int positionStart, int itemCount) {
            checkIfEmpty();
        }

        @Override
        public void onItemRangeRemoved(int positionStart, int itemCount) {
            checkIfEmpty();
        }
    };

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

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

    public EmptyRecyclerView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }

    void checkIfEmpty() {
        if (emptyView != null && getAdapter() != null) {
            final boolean emptyViewVisible = getAdapter().getItemCount() == 0;
            emptyView.setVisibility(emptyViewVisible ? VISIBLE : GONE);
            setVisibility(emptyViewVisible ? GONE : VISIBLE);
        }
    }

    @Override
    public void setAdapter(Adapter adapter) {
        final Adapter oldAdapter = getAdapter();
        if (oldAdapter != null) {
            oldAdapter.unregisterAdapterDataObserver(observer);
        }
        super.setAdapter(adapter);
        if (adapter != null) {
            adapter.registerAdapterDataObserver(observer);
        }

        checkIfEmpty();
    }

    public void setEmptyView(View emptyView) {
        this.emptyView = emptyView;
        checkIfEmpty();
    }
}

Answer 2

With the new data binding feature you can also achieve this in your layout directly:

<TextView
   android:text="No data to display."
   android:visibility="@{dataset.size() > 0 ? View.GONE : View.VISIBLE}" />

In that case you just need to add a variable and an import to the data section of your XML:

<data>
<import type="android.view.View"/>
<variable
    name="dataset"
    type="java.util.List&lt;java.lang.String&gt;"
    />
</data>

Answer 3

Solution provided in this link seems perfect. It uses viewType to identify when to show emptyView. No need to create custom RecyclerView

Adding code from the above link:

package com.example.androidsampleproject;
import java.util.ArrayList;
import java.util.List;
import android.app.Activity;
import android.os.Bundle;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

public class RecyclerViewActivity extends Activity {

RecyclerView recyclerView;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_recycler_view);
    recyclerView = (RecyclerView) findViewById(R.id.myList);
    recyclerView.setLayoutManager(new LinearLayoutManager(this));
    recyclerView.setAdapter(new MyAdapter());
}


private class MyAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
    private List<String> dataList = new ArrayList<String>();

    public class EmptyViewHolder extends RecyclerView.ViewHolder {
        public EmptyViewHolder(View itemView) {
            super(itemView);
        }
    }

    public class ViewHolder extends RecyclerView.ViewHolder {
        TextView data;

        public ViewHolder(View v) {
            super(v);
            data = (TextView) v.findViewById(R.id.data_view);
        }
    }

    @Override
    public int getItemCount() {
        return dataList.size() > 0 ? dataList.size() : 1;
    }

    @Override
    public int getItemViewType(int position) {
        if (dataList.size() == 0) {
            return EMPTY_VIEW;
        }
        return super.getItemViewType(position);
    }


    @Override
    public void onBindViewHolder(RecyclerView.ViewHolder vho, final int pos) {
        if (vho instanceof ViewHolder) {
            ViewHolder vh = (ViewHolder) vho;
            String pi = dataList.get(pos);
        }
    }

    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View v;

        if (viewType == EMPTY_VIEW) {
            v = LayoutInflater.from(parent.getContext()).inflate(R.layout.empty_view, parent, false);
            EmptyViewHolder evh = new EmptyViewHolder(v);
            return evh;
        }

        v = LayoutInflater.from(parent.getContext()).inflate(R.layout.data_row, parent, false);
        ViewHolder vh = new ViewHolder(v);
        return vh;
    }

    private static final int EMPTY_VIEW = 10;
}

}

Answer 4

I would simply prefer a simple solution like,

have your RecyclerView inside a FrameLayout or RelativeLayout with a TextView or other view with showing empty data message with visibility GONE by default and then in the adapter class, apply the logic

Here, I have one TextView with message no data

@Override
public int getItemCount() {
    textViewNoData.setVisibility(data.size() > 0 ? View.GONE : View.VISIBLE);
    return data.size();
}

Answer 5

If you want to support more states such as loading state, error state then you can checkout https://github.com/rockerhieu/rv-adapter-states. Otherwise supporting empty view can be implemented easily using RecyclerViewAdapterWrapper from (https://github.com/rockerhieu/rv-adapter). The main advantage of this approach is you can easily support empty view without changing the logic of the existing adapter:

public class StatesRecyclerViewAdapter extends RecyclerViewAdapterWrapper {
    private final View vEmptyView;

    @IntDef({STATE_NORMAL, STATE_EMPTY})
    @Retention(RetentionPolicy.SOURCE)
    public @interface State {
    }

    public static final int STATE_NORMAL = 0;
    public static final int STATE_EMPTY = 2;

    public static final int TYPE_EMPTY = 1001;

    @State
    private int state = STATE_NORMAL;

    public StatesRecyclerViewAdapter(@NonNull RecyclerView.Adapter wrapped, @Nullable View emptyView) {
        super(wrapped);
        this.vEmptyView = emptyView;
    }

    @State
    public int getState() {
        return state;
    }

    public void setState(@State int state) {
        this.state = state;
        getWrappedAdapter().notifyDataSetChanged();
        notifyDataSetChanged();
    }

    @Override
    public int getItemCount() {
        switch (state) {
            case STATE_EMPTY:
                return 1;
        }
        return super.getItemCount();
    }

    @Override
    public int getItemViewType(int position) {
        switch (state) {
            case STATE_EMPTY:
                return TYPE_EMPTY;
        }
        return super.getItemViewType(position);
    }

    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        switch (viewType) {
            case TYPE_EMPTY:
                return new SimpleViewHolder(vEmptyView);
        }
        return super.onCreateViewHolder(parent, viewType);
    }

    @Override
    public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
        switch (state) {
            case STATE_EMPTY:
                onBindEmptyViewHolder(holder, position);
                break;
            default:
                super.onBindViewHolder(holder, position);
                break;
        }
    }

    public void onBindEmptyViewHolder(RecyclerView.ViewHolder holder, int position) {
    }

    public static class SimpleViewHolder extends RecyclerView.ViewHolder {
        public SimpleViewHolder(View itemView) {
            super(itemView);
        }
    }
}

Usage:

Adapter adapter = originalAdapter();
StatesRecyclerViewAdapter statesRecyclerViewAdapter = new StatesRecyclerViewAdapter(adapter, emptyView);
rv.setAdapter(endlessRecyclerViewAdapter);

// Change the states of the adapter
statesRecyclerViewAdapter.setState(StatesRecyclerViewAdapter.STATE_EMPTY);
statesRecyclerViewAdapter.setState(StatesRecyclerViewAdapter.STATE_NORMAL);

Answer 6

Try RVEmptyObserver:

It's an implementation of an AdapterDataObserver that allows you to simply set a View as the default empty layout for your RecylerView. This way, instead of using a custom RecyclerView and making your life harder, you can easily use it with your existing code:

---

Example Usage:

RVEmptyObserver observer = new RVEmptyObserver(recyclerView, emptyView)
rvAdapter.registerAdapterDataObserver(observer);

You can see the code and example usage in an actual app here.

---

Class:

public class RVEmptyObserver extends RecyclerView.AdapterDataObserver {
    private View emptyView;
    private RecyclerView recyclerView;

    public RVEmptyObserver(RecyclerView rv, View ev) {
        this.recyclerView = rv;
        this.emptyView    = ev;
        checkIfEmpty();
    }

    private void checkIfEmpty() {
        if (emptyView != null && recyclerView.getAdapter() != null) {
            boolean emptyViewVisible = recyclerView.getAdapter().getItemCount() == 0;
            emptyView.setVisibility(emptyViewVisible ? View.VISIBLE : View.GONE);
            recyclerView.setVisibility(emptyViewVisible ? View.GONE : View.VISIBLE);
        }
    }

    public void onChanged() { checkIfEmpty(); }
    public void onItemRangeInserted(int positionStart, int itemCount) { checkIfEmpty(); }
    public void onItemRangeRemoved(int positionStart, int itemCount) { checkIfEmpty(); }
}

Answer 7

My version, based on https://gist.github.com/adelnizamutdinov/31c8f054d1af4588dc5c

public class EmptyRecyclerView extends RecyclerView {
    @Nullable
    private View emptyView;

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

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

    public EmptyRecyclerView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }

    private void checkIfEmpty() {
        if (emptyView != null && getAdapter() != null) {
            emptyView.setVisibility(getAdapter().getItemCount() > 0 ? GONE : VISIBLE);
        }
    }

    private final AdapterDataObserver observer = new AdapterDataObserver() {
        @Override
        public void onChanged() {
            checkIfEmpty();
        }

        @Override
        public void onItemRangeInserted(int positionStart, int itemCount) {
            checkIfEmpty();
        }

        @Override
        public void onItemRangeRemoved(int positionStart, int itemCount) {
            checkIfEmpty();
        }
    };

    @Override
    public void setAdapter(@Nullable Adapter adapter) {
        final Adapter oldAdapter = getAdapter();
        if (oldAdapter != null) {
            oldAdapter.unregisterAdapterDataObserver(observer);
        }
        super.setAdapter(adapter);
        if (adapter != null) {
            adapter.registerAdapterDataObserver(observer);
        }
        checkIfEmpty();
    }

    @Override
    public void setVisibility(int visibility) {
        super.setVisibility(visibility);
        if (null != emptyView && (visibility == GONE || visibility == INVISIBLE)) {
            emptyView.setVisibility(GONE);
        } else {
            checkIfEmpty();
        }
    }

    public void setEmptyView(@Nullable View emptyView) {
        this.emptyView = emptyView;
        checkIfEmpty();
    }
}

Answer 8

I would prefer to implement this functionality in Recycler.Adapter

On your overridden getItemCount method, inject empty check codes there:

@Override
public int getItemCount() {
    if(data.size() == 0) listIsEmtpy();
    return data.size();
}

Answer 9

I have fixed this:
Created layout layout_recyclerview_with_emptytext.xml file.
Created EmptyViewRecyclerView.java
---------

EmptyViewRecyclerView emptyRecyclerView = (EmptyViewRecyclerView) findViewById(R.id.emptyRecyclerViewLayout);
emptyRecyclerView.addAdapter(mPrayerCollectionRecyclerViewAdapter, "There is no prayer for selected category.");

layout_recyclerview_with_emptytext.xml file

    <?xml version="1.0" encoding="utf-8"?>
    <merge xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/switcher"
>

<android.support.v7.widget.RecyclerView
    android:id="@+id/recyclerView"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    />

<com.ninestars.views.CustomFontTextView android:id="@+id/recyclerViewEmptyTextView"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="Empty Text"
    android:layout_gravity="center"
    android:gravity="center"
    android:textStyle="bold"
    />

    </merge>

EmptyViewRecyclerView.java

public class EmptyViewRecyclerView extends ViewSwitcher {
private RecyclerView mRecyclerView;
private CustomFontTextView mRecyclerViewExptyTextView;

public EmptyViewRecyclerView(Context context) {
    super(context);
    initView(context);
}

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


private void initView(Context context) {
    LayoutInflater.from(context).inflate(R.layout.layout_recyclerview_with_emptytext, this, true);
    mRecyclerViewExptyTextView = (CustomFontTextView) findViewById(R.id.recyclerViewEmptyTextView);
    mRecyclerView = (RecyclerView) findViewById(R.id.recyclerView);
    mRecyclerView.setLayoutManager(new LinearLayoutManager(context));
}

public void addAdapter(final RecyclerView.Adapter<?> adapter) {
    mRecyclerView.setAdapter(adapter);
    adapter.registerAdapterDataObserver(new RecyclerView.AdapterDataObserver() {
        @Override
        public void onChanged() {
            super.onChanged();
            if(adapter.getItemCount() > 0) {
                if (R.id.recyclerView == getNextView().getId()) {
                    showNext();
                }
            } else {
                if (R.id.recyclerViewEmptyTextView == getNextView().getId()) {
                    showNext();
                }
            }
        }
    });
}

public void addAdapter(final RecyclerView.Adapter<?> adapter, String emptyTextMsg) {
    addAdapter(adapter);
    setEmptyText(emptyTextMsg);
}

public RecyclerView getRecyclerView() {
    return mRecyclerView;
}

public void setEmptyText(String emptyTextMsg) {
    mRecyclerViewExptyTextView.setText(emptyTextMsg);
}

}

Answer 10

public class EmptyRecyclerView extends RecyclerView {
  @Nullable View emptyView;

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

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

  public EmptyRecyclerView(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
  }

  void checkIfEmpty() {
    if (emptyView != null) {
      emptyView.setVisibility(getAdapter().getItemCount() > 0 ? GONE : VISIBLE);
    }
  }

  final @NotNull AdapterDataObserver observer = new AdapterDataObserver() {
    @Override public void onChanged() {
      super.onChanged();
      checkIfEmpty();
    }
  };

  @Override public void setAdapter(@Nullable Adapter adapter) {
    final Adapter oldAdapter = getAdapter();
    if (oldAdapter != null) {
      oldAdapter.unregisterAdapterDataObserver(observer);
    }
    super.setAdapter(adapter);
    if (adapter != null) {
      adapter.registerAdapterDataObserver(observer);
    }
  }

  public void setEmptyView(@Nullable View emptyView) {
    this.emptyView = emptyView;
    checkIfEmpty();
  }
}

something like this might help

Answer 11

I think this is more complete with both ErrorView & EmptyView https://gist.github.com/henrytao-me/2f7f113fb5f2a59987e7

Answer 12

You can just paint the text on the RecyclerView when it's empty. The following custom subclass supports empty, failed, loading, and offline modes. For successful compilation add recyclerView_stateText color to your resources.

/**
 * {@code RecyclerView} that supports loading and empty states.
 */
public final class SupportRecyclerView extends RecyclerView
{
    public enum State
    {
        NORMAL,
        LOADING,
        EMPTY,
        FAILED,
        OFFLINE
    }

    public SupportRecyclerView(@NonNull Context context)
    {
        super(context);

        setUp(context);
    }

    public SupportRecyclerView(@NonNull Context context, @Nullable AttributeSet attrs)
    {
        super(context, attrs);

        setUp(context);
    }

    public SupportRecyclerView(@NonNull Context context, @Nullable AttributeSet attrs, int defStyle)
    {
        super(context, attrs, defStyle);

        setUp(context);
    }

    private Paint textPaint;
    private Rect textBounds;
    private PointF textOrigin;

    private void setUp(Context c)
    {
        textPaint = new Paint();
        textPaint.setAntiAlias(true);
        textPaint.setColor(ContextCompat.getColor(c, R.color.recyclerView_stateText));

        textBounds = new Rect();
        textOrigin = new PointF();
    }

    private State state;

    public State state()
    {
        return state;
    }

    public void setState(State newState)
    {
        state = newState;
        calculateLayout(getWidth(), getHeight());
        invalidate();
    }

    private String loadingText = "Loading...";

    public void setLoadingText(@StringRes int resId)
    {
        loadingText = getResources().getString(resId);
    }

    private String emptyText = "Empty";

    public void setEmptyText(@StringRes int resId)
    {
        emptyText = getResources().getString(resId);
    }

    private String failedText = "Failed";

    public void setFailedText(@StringRes int resId)
    {
        failedText = getResources().getString(resId);
    }

    private String offlineText = "Offline";

    public void setOfflineText(@StringRes int resId)
    {
        offlineText = getResources().getString(resId);
    }

    @Override
    public void onDraw(Canvas canvas)
    {
        super.onDraw(canvas);

        String s = stringForCurrentState();
        if (s == null)
            return;

        canvas.drawText(s, textOrigin.x, textOrigin.y, textPaint);
    }

    private void calculateLayout(int w, int h)
    {
        String s = stringForCurrentState();
        if (s == null)
            return;

        textPaint.setTextSize(.1f * w);
        textPaint.getTextBounds(s, 0, s.length(), textBounds);

        textOrigin.set(
         w / 2f - textBounds.width() / 2f - textBounds.left,
         h / 2f - textBounds.height() / 2f - textBounds.top);
    }

    @Override
    protected void onSizeChanged(int w, int h, int oldw, int oldh)
    {
        super.onSizeChanged(w, h, oldw, oldh);

        calculateLayout(w, h);
    }

    private String stringForCurrentState()
    {
        if (state == State.EMPTY)
            return emptyText;
        else if (state == State.LOADING)
            return loadingText;
        else if (state == State.FAILED)
            return failedText;
        else if (state == State.OFFLINE)
            return offlineText;
        else
            return null;
    }
}

Answer 13

From my point of view the easiest way how to do an empty View is to create new empty RecyclerView with layout you want to inflate as a background. And this empty Adapter is set when you check your dataset size.

Answer 14

A more easy to use, and more resource save way to set Empty Label of RecyclerView.

In short, a new View named RecyclerViewEmpty is introduced. In its onDraw method, if the adapter is empty, it just paint an Empty Label on its center, otherwise, continue super.onDraw();

class RecyclerViewEmpty extends RecyclerView {
    ....
    @Override
    public void onDraw(Canvas canvas) {
        Adapter a = this.getAdapter();
        if(a==null || a.getItemCount()<1) {
            int x= (this.getWidth()-strWidth)>>1;
            int y = this.getHeight()>>1 ;
            canvas.drawText(this.emptyLabel, x, y, labelPaint);
        }
        else {
            super.onDraw(canvas);
        }
    }
    ....
}

For details, please refer to code: https://github.com/stzdzyhs/recyclerview-demo