Mettre une durée indéterminée progressbar que le pied de page dans un RecyclerView grille

Remarque solution ci-dessous a quelques problèmes potentiels et de la limitation, pour la révision des solution merci de vérifier celui-ci Ajout d'éléments à l'Infini Défilement RecyclerView avec Barre de progression en bas

Ici est solution je suis venu récemment:
l'idée est d'avoir RecyclerView avec 2 type d'éléments que l'on est notre habitude, les éléments de la deuxième est la barre de progression, puis nous avons besoin d'écouter de défilement de l'événement et de décider allons nous charger plus et de montrer progressbar ou pas.
Donc, à partir de l'idée à l'exemple de code

progress_item.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:orientation="vertical"
              android:layout_width="match_parent"
              android:layout_height="match_parent">

    <ProgressBar
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/progressBar"
        android:indeterminate="true"
        style="@android:style/Widget.Holo.ProgressBar"
        android:layout_gravity="center_horizontal"/>
</LinearLayout>

activity_main.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
                xmlns:tools="http://schemas.android.com/tools"
                xmlns:ring="http://schemas.android.com/apk/res-auto"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                tools:context=".MainActivity">

    <android.support.v7.widget.RecyclerView
        android:id="@+id/my_recycler_view"
        android:scrollbars="vertical"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>
</RelativeLayout>

EndlessRecyclerOnScrollListener.java

public abstract class EndlessRecyclerOnScrollListener extends RecyclerView.OnScrollListener {
    public static String TAG = EndlessRecyclerOnScrollListener.class.getSimpleName();

    private int previousTotal = 0; //The total number of items in the dataset after the last load
    private boolean loading = true; //True if we are still waiting for the last set of data to load.
    private int visibleThreshold = 1; //The minimum amount of items to have below your current scroll position before loading more.
    int firstVisibleItem, visibleItemCount, totalItemCount;

    private int current_page = 1;

    private LinearLayoutManager mLinearLayoutManager;

    public EndlessRecyclerOnScrollListener(LinearLayoutManager linearLayoutManager) {
        this.mLinearLayoutManager = linearLayoutManager;
    }

    @Override
    public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
        super.onScrolled(recyclerView, dx, dy);

        visibleItemCount = recyclerView.getChildCount();
        totalItemCount = mLinearLayoutManager.getItemCount();
        firstVisibleItem = mLinearLayoutManager.findFirstVisibleItemPosition();

        if (loading) {
            if (totalItemCount > previousTotal+1) {
                loading = false;
                previousTotal = totalItemCount;
            }
        }
        if (!loading && (totalItemCount - visibleItemCount) <= (firstVisibleItem + visibleThreshold)) {
        //End has been reached
        //Do something
            current_page++;
            onLoadMore(current_page);
            loading = true;
        }
    }

    public abstract void onLoadMore(int current_page);
}

MyAdapter.java

public class MyAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
private final int VIEW_ITEM = 1;
private final int VIEW_PROG = 0;
private List<String> mDataset;
public static class TextViewHolder extends RecyclerView.ViewHolder {
public TextView mTextView;
public TextViewHolder(View v) {
super(v);
mTextView = (TextView)v.findViewById(android.R.id.text1);
}
}
public static class ProgressViewHolder extends RecyclerView.ViewHolder {
public ProgressBar progressBar;
public ProgressViewHolder(View v) {
super(v);
progressBar = (ProgressBar)v.findViewById(R.id.progressBar);
}
}
public MyAdapter(List<String> myDataset) {
mDataset = myDataset;
}
@Override
public int getItemViewType(int position) {
return mDataset.get(position)!=null? VIEW_ITEM: VIEW_PROG;
}
@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
RecyclerView.ViewHolder vh;
if(viewType==VIEW_ITEM) {
View v = LayoutInflater.from(parent.getContext())
.inflate(android.R.layout.simple_list_item_1, parent, false);
vh = new TextViewHolder(v);
}else {
View v = LayoutInflater.from(parent.getContext())
.inflate(R.layout.progress_item, parent, false);
vh = new ProgressViewHolder(v);
}
return vh;
}
@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
if(holder instanceof TextViewHolder){
((TextViewHolder)holder).mTextView.setText(mDataset.get(position));
}else{
((ProgressViewHolder)holder).progressBar.setIndeterminate(true);
}
}
@Override
public int getItemCount() {
return mDataset.size();
}
}

et enfin MainActivity.java

package virtoos.com.testapps;
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import java.util.ArrayList;
import java.util.List;
public class MainActivity extends Activity {
private RecyclerView mRecyclerView;
private LinearLayoutManager mLayoutManager;
private MyAdapter mAdapter;
private final List<String> myDataset = new ArrayList<>();
private Handler handler;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
handler = new Handler();
addItems(20);
mRecyclerView = (RecyclerView) findViewById(R.id.my_recycler_view);
//use this setting to improve performance if you know that changes
//in content do not change the layout size of the RecyclerView
mRecyclerView.setHasFixedSize(true);
mLayoutManager = new LinearLayoutManager(this);
mRecyclerView.setLayoutManager(mLayoutManager);
mAdapter = new MyAdapter(myDataset);
mRecyclerView.setAdapter(mAdapter);
//mRecyclerView.setItemAnimator(new DefaultItemAnimator());
mRecyclerView.setOnScrollListener(new EndlessRecyclerOnScrollListener(mLayoutManager) {
@Override
public void onLoadMore(int current_page) {
//add progress item
myDataset.add(null);
mAdapter.notifyItemInserted(myDataset.size());
handler.postDelayed(new Runnable() {
@Override
public void run() {
//remove progress item
myDataset.remove(myDataset.size() - 1);
mAdapter.notifyItemRemoved(myDataset.size());
//add items one by one
for (int i = 0; i < 15; i++) {
myDataset.add("Item"+(myDataset.size()+1));
mAdapter.notifyItemInserted(myDataset.size());
}
//or you can add all at once but do not forget to call mAdapter.notifyDataSetChanged();
}
}, 2000);
System.out.println("load");
}
});
}
}

Découvrez ma solution dans https://github.com/ramirodo/endless-recycler-view-adapter
ou https://bintray.com/ramiro/android/endless-recycler-view-adapter. Il est un exemple là et aussi les étapes de configuration de la bibliothèque dans votre projet.

Vous avez juste besoin d'étendre votre recycleur de vue de l'adaptateur en mettant en œuvre les méthodes requises. Aussi, vous pouvez définir la mise en page de la progression de pied de page.