Merge pull request #150 from maitreyaverma/master

added infinite scrolling in placement blog

app/src/main/java/app/insti/adapter/PlacementBlogAdapter.java

@@ -2,9 +2,11 @@ package app.insti.adapter;
 
 import android.content.Context;
 import android.support.v7.widget.RecyclerView;
+import android.util.Log;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
+import android.widget.ProgressBar;
 import android.widget.TextView;
 
 import java.text.DateFormat;
@@ -17,9 +19,19 @@ import java.util.Locale;
 import app.insti.ItemClickListener;
 import app.insti.R;
 import app.insti.data.PlacementBlogPost;
+import app.insti.fragment.PlacementBlogFragment;
 import ru.noties.markwon.Markwon;
 
-public class PlacementBlogAdapter extends RecyclerView.Adapter<PlacementBlogAdapter.ViewHolder> {
+public class PlacementBlogAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
+    private final int VIEW_ITEM = 1;
+    private final int VIEW_PROG = 0;
+    public List<PlacementBlogPost> getPosts() {
+        return posts;
+    }
+
+    public void setPosts(List<PlacementBlogPost> posts) {
+        this.posts = posts;
+    }
 
     private List<PlacementBlogPost> posts;
     private Context context;
@@ -31,7 +43,8 @@ public class PlacementBlogAdapter extends RecyclerView.Adapter<PlacementBlogAdap
     }
 
     @Override
-    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
+    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
+        if(viewType==VIEW_ITEM){
             context = parent.getContext();
             LayoutInflater inflater = LayoutInflater.from(context);
             View postView = inflater.inflate(R.layout.blog_post_card, parent, false);
@@ -45,9 +58,28 @@ public class PlacementBlogAdapter extends RecyclerView.Adapter<PlacementBlogAdap
             });
             return postViewHolder;
         }
+        else{
+            LayoutInflater inflater=LayoutInflater.from(context);
+            View loadView=inflater.inflate(R.layout.blog_load_item,parent,false);
+            final PlacementBlogAdapter.ViewHolder postViewHolder = new PlacementBlogAdapter.ViewHolder(loadView);
+            return new PlacementBlogAdapter.ProgressViewHolder(loadView);
+        }
+    }
+    @Override
+    public int getItemViewType(int position) {
+        Log.d("position", String.valueOf(position));
+        return posts.size()> position ? VIEW_ITEM : VIEW_PROG;
+    }
+    @Override
+    public int getItemCount() {
+        return PlacementBlogFragment.showLoader? (posts.size()+1):posts.size();
+    }
+
 
     @Override
-    public void onBindViewHolder(ViewHolder holder, int position) {
+    public void onBindViewHolder(RecyclerView.ViewHolder recycleholder, int position) {
+        if(recycleholder instanceof ViewHolder){
+            ViewHolder holder=(ViewHolder)recycleholder;
             PlacementBlogPost post = posts.get(position);
             Markwon.setMarkdown(holder.postTitle, post.getTitle());
 
@@ -64,11 +96,11 @@ public class PlacementBlogAdapter extends RecyclerView.Adapter<PlacementBlogAdap
 
             Markwon.setMarkdown(holder.postContent, post.getContent());
         }
-
-    @Override
-    public int getItemCount() {
-        return posts.size();
+        else{
+            ((ProgressViewHolder)recycleholder).progressBar.setIndeterminate(true);
         }
+    }
+
 
     public class ViewHolder extends RecyclerView.ViewHolder {
         private TextView postTitle;
@@ -83,4 +115,12 @@ public class PlacementBlogAdapter extends RecyclerView.Adapter<PlacementBlogAdap
             postContent = (TextView) itemView.findViewById(R.id.post_content);
         }
     }
+    public static class ProgressViewHolder extends RecyclerView.ViewHolder {
+        public ProgressBar progressBar;
+        public ProgressViewHolder(View v) {
+            super(v);
+            progressBar = (ProgressBar)v.findViewById(R.id.blog_load_item);
+        }
+    }
+
 }

app/src/main/java/app/insti/api/RetrofitInterface.java

@@ -61,7 +61,7 @@ public interface RetrofitInterface {
     Call<Void> updateUserEventStatus(@Header("Cookie") String sessionID, @Path("eventID") String eventID, @Query("status") int status);
 
     @GET("placement-blog")
-    Call<List<PlacementBlogPost>> getPlacementBlogFeed(@Header("Cookie") String sessionID);
+    Call<List<PlacementBlogPost>> getPlacementBlogFeed(@Header("Cookie") String sessionID, @Query("from") int from,@Query("num") int num);
 
     @GET("training-blog")
     Call<List<TrainingBlogPost>> getTrainingBlogFeed(@Header("Cookie") String sessionID);

app/src/main/java/app/insti/fragment/PlacementBlogFragment.java

@@ -2,6 +2,7 @@ package app.insti.fragment;
 
 
 import android.app.Activity;
+import android.app.LauncherActivity;
 import android.content.Intent;
 import android.net.Uri;
 import android.os.AsyncTask;
@@ -11,10 +12,14 @@ import android.support.v4.widget.SwipeRefreshLayout;
 import android.support.v7.widget.LinearLayoutManager;
 import android.support.v7.widget.RecyclerView;
 import android.support.v7.widget.Toolbar;
+import android.util.Log;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 
+import com.google.android.gms.common.util.ListUtils;
+
+import java.util.ArrayList;
 import java.util.List;
 
 import app.insti.ActivityBuffer;
@@ -39,6 +44,7 @@ public class PlacementBlogFragment extends BaseFragment {
     private SwipeRefreshLayout feedSwipeRefreshLayout;
     private AppDatabase appDatabase;
     private boolean freshBlogDisplayed = false;
+    public static  boolean showLoader=true;
 
 
     public PlacementBlogFragment() {
@@ -76,7 +82,7 @@ public class PlacementBlogFragment extends BaseFragment {
 
     private void updatePlacementFeed() {
         RetrofitInterface retrofitInterface = ServiceGenerator.createService(RetrofitInterface.class);
-        retrofitInterface.getPlacementBlogFeed("sessionid=" + getArguments().getString(Constants.SESSION_ID)).enqueue(new Callback<List<PlacementBlogPost>>() {
+        retrofitInterface.getPlacementBlogFeed("sessionid=" + getArguments().getString(Constants.SESSION_ID),0,20).enqueue(new Callback<List<PlacementBlogPost>>() {
             @Override
             public void onResponse(Call<List<PlacementBlogPost>> call, Response<List<PlacementBlogPost>> response) {
                 if (response.isSuccessful()) {
@@ -115,6 +121,42 @@ public class PlacementBlogFragment extends BaseFragment {
                     placementFeedRecyclerView = getActivity().findViewById(R.id.placement_feed_recycler_view);
                     placementFeedRecyclerView.setAdapter(placementBlogAdapter);
                     placementFeedRecyclerView.setLayoutManager(new LinearLayoutManager(getContext()));
+                    placementFeedRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
+//                        multiple calls should not be made
+                        boolean loading=false;
+                        @Override
+                        public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
+                            if(dy>0){
+                                LinearLayoutManager layoutManager= (LinearLayoutManager) placementFeedRecyclerView.getLayoutManager();
+                                if(((layoutManager.getChildCount()+layoutManager.findFirstVisibleItemPosition())>(layoutManager.getItemCount()-5))&&(!loading)){
+                                    loading=true;
+                                    View v=getActivity().findViewById(R.id.placement_feed_swipe_refresh_layout);
+                                    RetrofitInterface retrofitInterface = ServiceGenerator.createService(RetrofitInterface.class);
+                                    retrofitInterface.getPlacementBlogFeed("sessionid=" +getArguments().getString(Constants.SESSION_ID),layoutManager.getItemCount(),10).enqueue(new Callback<List<PlacementBlogPost>>() {
+                                        @Override
+                                        public void onResponse(Call<List<PlacementBlogPost>> call, Response<List<PlacementBlogPost>> response) {
+
+                                            loading=false;
+                                            List<PlacementBlogPost> blogPosts= (ArrayList<PlacementBlogPost>) placementBlogAdapter.getPosts();
+                                            blogPosts.addAll(response.body());
+                                            if(response.body().size()==0){
+                                                showLoader=false;
+                                            }
+                                            placementBlogAdapter.setPosts(blogPosts);
+                                            placementBlogAdapter.notifyDataSetChanged();
+//                                            new updateDatabase().execute(blogPosts);
+                                        }
+
+                                        @Override
+                                        public void onFailure(Call<List<PlacementBlogPost>> call, Throwable t) {
+                                            loading=false;
+                                        }
+                                    });
+                                }
+
+                            }
+                        }
+                    });
                 } catch (NullPointerException e) {
                     e.printStackTrace();
                 }

app/src/main/res/layout/blog_load_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="wrap_content">
+    <ProgressBar
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:indeterminate="true"
+        android:id="@+id/blog_load_item"
+        android:layout_gravity="center_horizontal"
+        android:layout_margin="@dimen/activity_vertical_margin"/>
+</LinearLayout>
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