Load parent-level comments using pagination. Only load comments of comments once more.

7 files changed, 85 insertions, 55 deletions

diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/CommentAdapter.java b/app/src/main/java/ml/docilealligator/infinityforreddit/CommentAdapter.java
index 1ec848ad..ca0ec181 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/CommentAdapter.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/CommentAdapter.java
@@ -1,16 +1,10 @@
 package ml.docilealligator.infinityforreddit;
 
-import androidx.paging.PagedListAdapter;
 import android.content.Context;
 import android.content.Intent;
 import android.content.SharedPreferences;
 import android.graphics.ColorFilter;
 import android.net.Uri;
-import androidx.annotation.NonNull;
-import androidx.browser.customtabs.CustomTabsIntent;
-import androidx.core.content.ContextCompat;
-import androidx.recyclerview.widget.DiffUtil;
-import androidx.recyclerview.widget.RecyclerView;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
@@ -21,9 +15,16 @@ import android.widget.Toast;
 
 import com.multilevelview.models.RecyclerViewItem;
 
+import java.util.ArrayList;
 import java.util.List;
 import java.util.Locale;
 
+import androidx.annotation.NonNull;
+import androidx.browser.customtabs.CustomTabsIntent;
+import androidx.core.content.ContextCompat;
+import androidx.paging.PagedListAdapter;
+import androidx.recyclerview.widget.DiffUtil;
+import androidx.recyclerview.widget.RecyclerView;
 import butterknife.BindView;
 import butterknife.ButterKnife;
 import retrofit2.Retrofit;
@@ -128,7 +129,7 @@ public class CommentAdapter extends PagedListAdapter<CommentData, RecyclerView.V
                         locale, false, commentItem.getDepth(), new FetchComment.FetchCommentListener() {
                             @Override
                             public void onFetchCommentSuccess(List<?> commentData,
-                                                              String parentId, String commaSeparatedChildren) {
+                                                              String parentId, ArrayList<String> children) {
                                 commentItem.addChildren((List<RecyclerViewItem>) commentData);
                                 ((CommentViewHolder) viewHolder).loadMoreCommentsProgressBar
                                         .setVisibility(View.GONE);
@@ -140,7 +141,7 @@ public class CommentAdapter extends PagedListAdapter<CommentData, RecyclerView.V
                                         new ParseComment.ParseCommentListener() {
                                             @Override
                                             public void onParseCommentSuccess(List<?> commentData,
-                                                                              String parentId, String commaSeparatedChildren) {
+                                                                              String parentId, String children) {
                                                 commentItem.addChildren((List<RecyclerViewItem>) commentData);
                                                 ((CommentViewHolder) viewHolder).loadMoreCommentsProgressBar
                                                         .setVisibility(View.GONE);
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/CommentDataSource.java b/app/src/main/java/ml/docilealligator/infinityforreddit/CommentDataSource.java
index 99084dbf..a7fd32cd 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/CommentDataSource.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/CommentDataSource.java
@@ -1,17 +1,11 @@
 package ml.docilealligator.infinityforreddit;
 
-import androidx.lifecycle.MutableLiveData;
-import androidx.paging.PageKeyedDataSource;
-import androidx.annotation.NonNull;
-import android.util.Log;
-
-import java.util.ArrayList;
-import java.util.List;
 import java.util.Locale;
 
+import androidx.annotation.NonNull;
+import androidx.lifecycle.MutableLiveData;
+import androidx.paging.PageKeyedDataSource;
 import retrofit2.Call;
-import retrofit2.Callback;
-import retrofit2.Response;
 import retrofit2.Retrofit;
 
 public class CommentDataSource extends PageKeyedDataSource<String, Post> {
@@ -69,7 +63,7 @@ public class CommentDataSource extends PageKeyedDataSource<String, Post> {
         RedditAPI api = retrofit.create(RedditAPI.class);
 
         Call<String> comments = api.getComments(subredditNamePrefixed, article, comment);
-        comments.enqueue(new Callback<String>() {
+        /*comments.enqueue(new Callback<String>() {
             @Override
             public void onResponse(@NonNull Call<String> call, @NonNull Response<String> response) {
                 if(response.isSuccessful()) {
@@ -104,7 +98,7 @@ public class CommentDataSource extends PageKeyedDataSource<String, Post> {
             public void onFailure(@NonNull Call<String> call, @NonNull Throwable t) {
                 initialLoadStateLiveData.postValue(new NetworkState(NetworkState.Status.FAILED, "Error fetching comment"));
             }
-        });
+        });*/
     }
 
     @Override
@@ -126,7 +120,7 @@ public class CommentDataSource extends PageKeyedDataSource<String, Post> {
         RedditAPI api = retrofit.create(RedditAPI.class);
 
         Call<String> moreChildrenBasicInfo = api.getMoreChildren(mParentId, params.key);
-        moreChildrenBasicInfo.enqueue(new Callback<String>() {
+        /*moreChildrenBasicInfo.enqueue(new Callback<String>() {
             @Override
             public void onResponse(Call<String> call, Response<String> response) {
                 if(response.isSuccessful()) {
@@ -182,7 +176,7 @@ public class CommentDataSource extends PageKeyedDataSource<String, Post> {
                 String errorMessage = t == null ? "unknown error" : t.getMessage();
                 paginationNetworkStateLiveData.postValue(new NetworkState(NetworkState.Status.FAILED, errorMessage));
             }
-        });
+        });*/
     }
 
     void retry() {
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/FetchComment.java b/app/src/main/java/ml/docilealligator/infinityforreddit/FetchComment.java
index c4a4ea00..a9151b50 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/FetchComment.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/FetchComment.java
@@ -15,12 +15,12 @@ import retrofit2.Retrofit;
 class FetchComment {
     interface FetchCommentListener {
         void onFetchCommentSuccess(List<?> commentData,
-                                   String parentId, String commaSeparatedChildren);
+                                   String parentId, ArrayList<String> children);
         void onFetchCommentFailed();
     }
 
     interface FetchMoreCommentListener {
-        void onFetchMoreCommentSuccess(List<?> commentData);
+        void onFetchMoreCommentSuccess(List<?> commentData, int childrenStartingIndex);
         void onFetchMoreCommentFailed();
     }
 
@@ -43,9 +43,9 @@ class FetchComment {
                             new ParseComment.ParseCommentListener() {
                                 @Override
                                 public void onParseCommentSuccess(List<?> commentData,
-                                                                  String parentId, String commaSeparatedChildren) {
+                                                                  String parentId, ArrayList<String> children) {
                                     fetchCommentListener.onFetchCommentSuccess(commentData, parentId,
-                                            commaSeparatedChildren);
+                                            children);
                                 }
 
                                 @Override
@@ -69,9 +69,25 @@ class FetchComment {
     }
 
     static void fetchMoreComment(Retrofit retrofit, String subredditNamePrefixed, String mParentId,
-                                 String children, Locale locale, FetchMoreCommentListener fetchMoreCommentListener) {
+                                 ArrayList<String> allChildren, int startingIndex, Locale locale,
+                                 FetchMoreCommentListener fetchMoreCommentListener) {
+        StringBuilder stringBuilder = new StringBuilder();
+        for(int i = 0; i < 100; i++) {
+            if(allChildren.size() <= startingIndex + i) {
+                break;
+            }
+            stringBuilder.append(allChildren.get(startingIndex + i)).append(",");
+        }
+
+        if(stringBuilder.length() == 0) {
+            return;
+        }
+
+        stringBuilder.deleteCharAt(stringBuilder.length() - 1);
+        //final int finalStartingIndex = startingIndex + 100;
+
         RedditAPI api = retrofit.create(RedditAPI.class);
-        Call<String> moreChildrenBasicInfo = api.getMoreChildren(mParentId, children);
+        Call<String> moreChildrenBasicInfo = api.getMoreChildren(mParentId, stringBuilder.toString());
         moreChildrenBasicInfo.enqueue(new Callback<String>() {
             @Override
             public void onResponse(Call<String> call, Response<String> response) {
@@ -88,8 +104,11 @@ class FetchComment {
                                                 0, new ParseComment.ParseCommentListener() {
                                                     @Override
                                                     public void onParseCommentSuccess(List<?> commentData, String parentId,
-                                                                                      String commaSeparatedChildren) {
-                                                        fetchMoreCommentListener.onFetchMoreCommentSuccess(commentData);
+                                                                                      ArrayList<String> children) {
+                                                        fetchMoreCommentListener.onFetchMoreCommentSuccess(commentData, startingIndex + 100);
+                                                        /*fetchMoreComment(retrofit, subredditNamePrefixed,
+                                                                mParentId, allChildren, finalStartingIndex,
+                                                                locale, fetchMoreCommentListener);*/
                                                     }
 
                                                     @Override
@@ -138,12 +157,13 @@ class FetchComment {
         fetchComment(retrofit, subredditNamePrefixed, article, comment, locale, isPost, parentDepth,
                 new FetchCommentListener() {
                     @Override
-                    public void onFetchCommentSuccess(List<?> commentData, String parentId, String commaSeparatedChildren) {
-                        if(!commaSeparatedChildren.equals("")) {
-                            fetchMoreComment(retrofit, subredditNamePrefixed, parentId, commaSeparatedChildren,
-                                    locale, new FetchMoreCommentListener() {
+                    public void onFetchCommentSuccess(List<?> commentData, String parentId, ArrayList<String> children) {
+                        if(children.size() != 0) {
+                            fetchMoreComment(retrofit, subredditNamePrefixed, parentId, children,
+                                    0, locale, new FetchMoreCommentListener() {
                                         @Override
-                                        public void onFetchMoreCommentSuccess(List<?> moreCommentData) {
+                                        public void onFetchMoreCommentSuccess(List<?> moreCommentData,
+                                                                              int childrenStartingIndex) {
                                             ((ArrayList<CommentData>)commentData).addAll((ArrayList<CommentData>) moreCommentData);
                                             fetchAllCommentListener.onFetchAllCommentSuccess(commentData);
                                         }
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/MainActivity.java b/app/src/main/java/ml/docilealligator/infinityforreddit/MainActivity.java
index 3aec9917..7591885f 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/MainActivity.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/MainActivity.java
@@ -147,7 +147,7 @@ public class MainActivity extends AppCompatActivity {
             @Override
             public void onSearchViewClosed() {
                 transparentOverlay.setVisibility(View.GONE);
-                getWindow().setStatusBarColor(getResources().getColor(R.color.colorPrimaryDark));
+                getWindow().setStatusBarColor(Color.TRANSPARENT);
             }
 
             @Override
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/ParseComment.java b/app/src/main/java/ml/docilealligator/infinityforreddit/ParseComment.java
index 92b5f10b..970c9ed6 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/ParseComment.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/ParseComment.java
@@ -15,7 +15,7 @@ import java.util.Locale;
 
 class ParseComment {
     interface ParseCommentListener {
-        void onParseCommentSuccess(List<?> commentData, String parentId, String commaSeparatedChildren);
+        void onParseCommentSuccess(List<?> commentData, String parentId, ArrayList<String> children);
         void onParseCommentFailed();
     }
 
@@ -64,7 +64,7 @@ class ParseComment {
         private JSONArray comments;
         private ArrayList<CommentData> commentData;
         private ArrayList<CommentData> newcommentData;
-        private StringBuilder commaSeparatedChildren;
+        private ArrayList<String> children;
         private Locale locale;
         private int parentDepth;
         private ParseCommentListener parseCommentListener;
@@ -76,7 +76,7 @@ class ParseComment {
             this.comments = comments;
             this.commentData = commentData;
             newcommentData = new ArrayList<>();
-            commaSeparatedChildren = new StringBuilder();
+            children = new ArrayList<>();
             this.locale = locale;
             this.parentDepth = parentDepth;
             parseFailed = false;
@@ -87,7 +87,6 @@ class ParseComment {
         protected Void doInBackground(Void... voids) {
             try {
                 int actualCommentLength;
-                ArrayList<String> children = new ArrayList<>();
 
                 if(comments.length() == 0) {
                     return null;
@@ -104,11 +103,6 @@ class ParseComment {
                         children.add(childrenArray.getString(i));
                     }
 
-                    for(String c : children) {
-                        commaSeparatedChildren.append(c).append(",");
-                    }
-                    commaSeparatedChildren.deleteCharAt(commaSeparatedChildren.length() - 1);
-
                     actualCommentLength = comments.length() - 1;
                 } else {
                     actualCommentLength = comments.length();
@@ -156,7 +150,7 @@ class ParseComment {
         protected void onPostExecute(Void aVoid) {
             if(!parseFailed) {
                 commentData.addAll(newcommentData);
-                parseCommentListener.onParseCommentSuccess(commentData, parentId, commaSeparatedChildren.toString());
+                parseCommentListener.onParseCommentSuccess(commentData, parentId, children);
             } else {
                 parseCommentListener.onParseCommentFailed();
             }
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/ViewPostDetailActivity.java b/app/src/main/java/ml/docilealligator/infinityforreddit/ViewPostDetailActivity.java
index df66d631..b9a75a40 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/ViewPostDetailActivity.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/ViewPostDetailActivity.java
@@ -9,6 +9,7 @@ import android.net.Uri;
 import android.os.Bundle;
 import android.view.MenuItem;
 import android.view.View;
+import android.view.ViewTreeObserver;
 import android.widget.ImageView;
 import android.widget.LinearLayout;
 import android.widget.ProgressBar;
@@ -44,6 +45,7 @@ import androidx.browser.customtabs.CustomTabsIntent;
 import androidx.cardview.widget.CardView;
 import androidx.coordinatorlayout.widget.CoordinatorLayout;
 import androidx.core.content.ContextCompat;
+import androidx.core.widget.NestedScrollView;
 import androidx.recyclerview.widget.DividerItemDecoration;
 import androidx.recyclerview.widget.LinearLayoutManager;
 import butterknife.BindView;
@@ -66,9 +68,12 @@ public class ViewPostDetailActivity extends AppCompatActivity {
 
     private Post mPost;
 
-    private String mCommaSeparatedChildren;
+    private boolean isLoadingMoreChildren = false;
+    private ArrayList<String> children;
+    private int mChildrenStartingIndex = 0;
 
     @BindView(R.id.coordinator_layout_view_post_detail) CoordinatorLayout mCoordinatorLayout;
+    @BindView(R.id.nested_scroll_view_view_post_detail_activity) NestedScrollView mNestedScrollView;
     @BindView(R.id.subreddit_icon_name_linear_layout_view_post_detail) LinearLayout mSubredditIconNameLinearLayout;
     @BindView(R.id.subreddit_icon_circle_image_view_view_post_detail) AspectRatioGifImageView mSubredditIconGifImageView;
     @BindView(R.id.subreddit_text_view_view_post_detail) TextView mSubredditTextView;
@@ -446,8 +451,8 @@ public class ViewPostDetailActivity extends AppCompatActivity {
                 null, getResources().getConfiguration().locale, true, 0, new FetchComment.FetchCommentListener() {
                     @Override
                     public void onFetchCommentSuccess(List<?> commentData,
-                                                      String parentId, String commaSeparatedChildren) {
-                        mCommaSeparatedChildren = commaSeparatedChildren;
+                                                      String parentId, ArrayList<String> children) {
+                        ViewPostDetailActivity.this.children = children;
                         mCommentProgressbar.setVisibility(View.GONE);
                         if (commentData.size() > 0) {
                             mAdapter = new CommentMultiLevelRecyclerViewAdapter(
@@ -461,9 +466,19 @@ public class ViewPostDetailActivity extends AppCompatActivity {
                             mRecyclerView.setAdapter(mAdapter);
                             mCommentCardView.setVisibility(View.VISIBLE);
 
-                            if(!mCommaSeparatedChildren.equals("")) {
-                                fetchMoreComment();
-                            }
+                            mNestedScrollView.getViewTreeObserver().addOnScrollChangedListener(new ViewTreeObserver.OnScrollChangedListener() {
+                                @Override
+                                public void onScrollChanged() {
+                                    if(!isLoadingMoreChildren) {
+                                        View view = mNestedScrollView.getChildAt(mNestedScrollView.getChildCount() - 1);
+                                        int diff = view.getBottom() - (mNestedScrollView.getHeight() +
+                                                mNestedScrollView.getScrollY());
+                                        if(diff == 0) {
+                                            fetchMoreComment(mChildrenStartingIndex);
+                                        }
+                                    }
+                                }
+                            });
                         } else {
                             mNoCommentWrapperLinearLayout.setVisibility(View.VISIBLE);
                             glide.load(R.drawable.no_comment_indicator).into(mNoCommentImageView);
@@ -478,18 +493,23 @@ public class ViewPostDetailActivity extends AppCompatActivity {
                 });
     }
 
-    private void fetchMoreComment() {
+    private void fetchMoreComment(int startingIndex) {
+        isLoadingMoreChildren = true;
         FetchComment.fetchMoreComment(mRetrofit, mPost.getSubredditNamePrefixed(), mPost.getFullName(),
-                mCommaSeparatedChildren, getResources().getConfiguration().locale, new FetchComment.FetchMoreCommentListener() {
+                children, startingIndex, getResources().getConfiguration().locale,
+                new FetchComment.FetchMoreCommentListener() {
                     @Override
-                    public void onFetchMoreCommentSuccess(List<?> commentData) {
+                    public void onFetchMoreCommentSuccess(List<?> commentData, int childrenStartingIndex) {
                         mAdapter.addComments((ArrayList<CommentData>) commentData);
+                        mChildrenStartingIndex = childrenStartingIndex;
+                        isLoadingMoreChildren = false;
                     }
 
                     @Override
                     public void onFetchMoreCommentFailed() {
+                        isLoadingMoreChildren = false;
                         Snackbar snackbar = Snackbar.make(mCoordinatorLayout, R.string.load_more_comment_failed, Snackbar.LENGTH_INDEFINITE);
-                        snackbar.setAction(R.string.retry, view -> fetchMoreComment());
+                        snackbar.setAction(R.string.retry, view -> fetchMoreComment(startingIndex));
                         snackbar.show();
                     }
                 });
diff --git a/app/src/main/res/layout/activity_view_post_detail.xml b/app/src/main/res/layout/activity_view_post_detail.xml
index 0f7c2002..1a0be45d 100644
--- a/app/src/main/res/layout/activity_view_post_detail.xml
+++ b/app/src/main/res/layout/activity_view_post_detail.xml
@@ -8,6 +8,7 @@
     tools:context=".ViewPostDetailActivity">
 
     <androidx.core.widget.NestedScrollView
+        android:id="@+id/nested_scroll_view_view_post_detail_activity"
         android:layout_width="match_parent"
         android:layout_height="wrap_content">