Viewing rules after pressing rules button in PostXXXActivity is available. Extend MarkwonView to support opening reddit subreddit and user links.

21 files changed, 443 insertions, 59 deletions

diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index 11a36158..24a79054 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -20,6 +20,10 @@
         android:theme="@style/AppTheme"
         android:usesCleartextTraffic="true">
         <activity
+            android:name=".RulesActivity"
+            android:label="@string/rules_activity_label"
+            android:parentActivityName=".MainActivity" />
+        <activity
             android:name=".PostVideoActivity"
             android:label="@string/post_video_activity_label"
             android:parentActivityName=".MainActivity"
diff --git a/app/src/main/java/CustomView/CustomMarkwonView.java b/app/src/main/java/CustomView/CustomMarkwonView.java
new file mode 100644
index 00000000..c0d59f05
--- /dev/null
+++ b/app/src/main/java/CustomView/CustomMarkwonView.java
@@ -0,0 +1,49 @@
+package CustomView;
+
+import android.content.Context;
+import android.content.Intent;
+import android.net.Uri;
+import android.util.AttributeSet;
+
+import androidx.annotation.Nullable;
+import androidx.browser.customtabs.CustomTabsIntent;
+
+import ml.docilealligator.infinityforreddit.R;
+import ml.docilealligator.infinityforreddit.ViewSubredditDetailActivity;
+import ml.docilealligator.infinityforreddit.ViewUserDetailActivity;
+import ru.noties.markwon.SpannableConfiguration;
+import ru.noties.markwon.view.MarkwonView;
+
+public class CustomMarkwonView extends MarkwonView {
+
+    public CustomMarkwonView(Context context) {
+        super(context);
+    }
+
+    public CustomMarkwonView(Context context, AttributeSet attrs) {
+        super(context, attrs);
+    }
+
+    public void setMarkdown(@Nullable String markdown, Context conte) {
+        SpannableConfiguration configuration = SpannableConfiguration.builder(conte).linkResolver((view, link) -> {
+            if(link.startsWith("/u/") || link.startsWith("u/")) {
+                Intent intent = new Intent(conte, ViewUserDetailActivity.class);
+                intent.putExtra(ViewUserDetailActivity.EXTRA_USER_NAME_KEY, link.substring(3));
+                conte.startActivity(intent);
+            } else if(link.startsWith("/r/") || link.startsWith("r/")) {
+                Intent intent = new Intent(conte, ViewSubredditDetailActivity.class);
+                intent.putExtra(ViewSubredditDetailActivity.EXTRA_SUBREDDIT_NAME_KEY, link.substring(3));
+                conte.startActivity(intent);
+            } else {
+                CustomTabsIntent.Builder builder = new CustomTabsIntent.Builder();
+                // add share action to menu list
+                builder.addDefaultShareMenuItem();
+                builder.setToolbarColor(conte.getResources().getColor(R.color.colorPrimary));
+                CustomTabsIntent customTabsIntent = builder.build();
+                customTabsIntent.launchUrl(conte, Uri.parse(link));
+            }
+        }).build();
+
+        super.setMarkdown(configuration, markdown);
+    }
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/AppComponent.java b/app/src/main/java/ml/docilealligator/infinityforreddit/AppComponent.java
index da7da984..87c4f254 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/AppComponent.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/AppComponent.java
@@ -23,4 +23,5 @@ interface AppComponent {
     void inject(PostImageActivity postImageActivity);
     void inject(PostVideoActivity postVideoActivity);
     void inject(FlairBottomSheetFragment flairBottomSheetFragment);
+    void inject(RulesActivity rulesActivity);
 }
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/CommentRecyclerViewAdapter.java b/app/src/main/java/ml/docilealligator/infinityforreddit/CommentAndPostRecyclerViewAdapter.java
index 32b023be..3bb3ef10 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/CommentRecyclerViewAdapter.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/CommentAndPostRecyclerViewAdapter.java
@@ -39,6 +39,7 @@ import java.util.ArrayList;
 import java.util.Locale;
 
 import CustomView.AspectRatioGifImageView;
+import CustomView.CustomMarkwonView;
 import SubredditDatabase.SubredditRoomDatabase;
 import User.UserRoomDatabase;
 import butterknife.BindView;
@@ -46,10 +47,8 @@ import butterknife.ButterKnife;
 import jp.wasabeef.glide.transformations.BlurTransformation;
 import jp.wasabeef.glide.transformations.RoundedCornersTransformation;
 import retrofit2.Retrofit;
-import ru.noties.markwon.SpannableConfiguration;
-import ru.noties.markwon.view.MarkwonView;
 
-class CommentRecyclerViewAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
+class CommentAndPostRecyclerViewAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
     private static final int VIEW_TYPE_POST_DETAIL = 0;
     private static final int VIEW_TYPE_FIRST_LOADING = 1;
     private static final int VIEW_TYPE_FIRST_LOADING_FAILED = 2;
@@ -80,10 +79,10 @@ class CommentRecyclerViewAdapter extends RecyclerView.Adapter<RecyclerView.ViewH
         void retryFetchingMoreComments();
     }
 
-    CommentRecyclerViewAdapter(Activity activity, Retrofit retrofit, Retrofit oauthRetrofit, RequestManager glide,
-                               SharedPreferences sharedPreferences, Post post, String subredditNamePrefixed,
-                               Locale locale, LoadSubredditIconAsyncTask loadSubredditIconAsyncTask,
-                               CommentRecyclerViewAdapterCallback commentRecyclerViewAdapterCallback) {
+    CommentAndPostRecyclerViewAdapter(Activity activity, Retrofit retrofit, Retrofit oauthRetrofit, RequestManager glide,
+                                      SharedPreferences sharedPreferences, Post post, String subredditNamePrefixed,
+                                      Locale locale, LoadSubredditIconAsyncTask loadSubredditIconAsyncTask,
+                                      CommentRecyclerViewAdapterCallback commentRecyclerViewAdapterCallback) {
         mActivity = activity;
         mRetrofit = retrofit;
         mOauthRetrofit = oauthRetrofit;
@@ -372,7 +371,7 @@ class CommentRecyclerViewAdapter extends RecyclerView.Adapter<RecyclerView.ViewH
 
                     if(!mPost.getSelfText().equals("")) {
                         ((PostDetailViewHolder) holder).mContentMarkdownView.setVisibility(View.VISIBLE);
-                        ((PostDetailViewHolder) holder).mContentMarkdownView.setMarkdown(getCustomSpannableConfiguration(), mPost.getSelfText());
+                        ((PostDetailViewHolder) holder).mContentMarkdownView.setMarkdown(mPost.getSelfText(), mActivity);
                     }
                     ((PostDetailViewHolder) holder).mNoPreviewLinkImageView.setVisibility(View.VISIBLE);
                     ((PostDetailViewHolder) holder).mNoPreviewLinkImageView.setOnClickListener(view -> {
@@ -389,7 +388,7 @@ class CommentRecyclerViewAdapter extends RecyclerView.Adapter<RecyclerView.ViewH
 
                     if(!mPost.getSelfText().equals("")) {
                         ((PostDetailViewHolder) holder).mContentMarkdownView.setVisibility(View.VISIBLE);
-                        ((PostDetailViewHolder) holder).mContentMarkdownView.setMarkdown(getCustomSpannableConfiguration(), mPost.getSelfText());
+                        ((PostDetailViewHolder) holder).mContentMarkdownView.setMarkdown(mPost.getSelfText(), mActivity);
                     }
                     break;
             }
@@ -401,26 +400,7 @@ class CommentRecyclerViewAdapter extends RecyclerView.Adapter<RecyclerView.ViewH
 
             ((CommentViewHolder) holder).commentTimeTextView.setText(comment.getCommentTime());
 
-            SpannableConfiguration spannableConfiguration = SpannableConfiguration.builder(mActivity).linkResolver((view, link) -> {
-                if (link.startsWith("/u/") || link.startsWith("u/")) {
-                    Intent intent = new Intent(mActivity, ViewUserDetailActivity.class);
-                    intent.putExtra(ViewUserDetailActivity.EXTRA_USER_NAME_KEY, link.substring(3));
-                    mActivity.startActivity(intent);
-                } else if (link.startsWith("/r/") || link.startsWith("r/")) {
-                    Intent intent = new Intent(mActivity, ViewSubredditDetailActivity.class);
-                    intent.putExtra(ViewSubredditDetailActivity.EXTRA_SUBREDDIT_NAME_KEY, link.substring(3));
-                    mActivity.startActivity(intent);
-                } else {
-                    CustomTabsIntent.Builder builder = new CustomTabsIntent.Builder();
-                    // add share action to menu list
-                    builder.addDefaultShareMenuItem();
-                    builder.setToolbarColor(mActivity.getResources().getColor(R.color.colorPrimary));
-                    CustomTabsIntent customTabsIntent = builder.build();
-                    customTabsIntent.launchUrl(mActivity, Uri.parse(link));
-                }
-            }).build();
-
-            ((CommentViewHolder) holder).commentMarkdownView.setMarkdown(spannableConfiguration, comment.getCommentContent());
+            ((CommentViewHolder) holder).commentMarkdownView.setMarkdown(comment.getCommentContent(), mActivity);
             ((CommentViewHolder) holder).scoreTextView.setText(Integer.toString(comment.getScore()));
 
             ViewGroup.LayoutParams params = ((CommentViewHolder) holder).verticalBlock.getLayoutParams();
@@ -497,27 +477,6 @@ class CommentRecyclerViewAdapter extends RecyclerView.Adapter<RecyclerView.ViewH
         }
     }
 
-    private SpannableConfiguration getCustomSpannableConfiguration() {
-        return SpannableConfiguration.builder(mActivity).linkResolver((view, link) -> {
-            if(link.startsWith("/u/") || link.startsWith("u/")) {
-                Intent intent = new Intent(mActivity, ViewUserDetailActivity.class);
-                intent.putExtra(ViewUserDetailActivity.EXTRA_USER_NAME_KEY, link.substring(3));
-                mActivity.startActivity(intent);
-            } else if(link.startsWith("/r/") || link.startsWith("r/")) {
-                Intent intent = new Intent(mActivity, ViewSubredditDetailActivity.class);
-                intent.putExtra(ViewSubredditDetailActivity.EXTRA_SUBREDDIT_NAME_KEY, link.substring(3));
-                mActivity.startActivity(intent);
-            } else {
-                CustomTabsIntent.Builder builder = new CustomTabsIntent.Builder();
-                // add share action to menu list
-                builder.addDefaultShareMenuItem();
-                builder.setToolbarColor(mActivity.getResources().getColor(R.color.colorPrimary));
-                CustomTabsIntent customTabsIntent = builder.build();
-                customTabsIntent.launchUrl(mActivity, Uri.parse(link));
-            }
-        }).build();
-    }
-
     void updatePost(Post post) {
         mPost = post;
         notifyItemChanged(0);
@@ -689,7 +648,7 @@ class CommentRecyclerViewAdapter extends RecyclerView.Adapter<RecyclerView.ViewH
         @BindView(R.id.subreddit_text_view_item_post_detail) TextView mSubredditTextView;
         @BindView(R.id.post_time_text_view_item_post_detail) TextView mPostTimeTextView;
         @BindView(R.id.title_text_view_item_post_detail) TextView mTitleTextView;
-        @BindView(R.id.content_markdown_view_item_post_detail) MarkwonView mContentMarkdownView;
+        @BindView(R.id.content_markdown_view_item_post_detail) CustomMarkwonView mContentMarkdownView;
         @BindView(R.id.type_text_view_item_post_detail) Chip mTypeChip;
         @BindView(R.id.gilded_image_view_item_post_detail) ImageView mGildedImageView;
         @BindView(R.id.gilded_number_text_view_item_post_detail) TextView mGildedNumberTextView;
@@ -848,7 +807,7 @@ class CommentRecyclerViewAdapter extends RecyclerView.Adapter<RecyclerView.ViewH
     class CommentViewHolder extends RecyclerView.ViewHolder {
         @BindView(R.id.author_text_view_item_post_comment) TextView authorTextView;
         @BindView(R.id.comment_time_text_view_item_post_comment) TextView commentTimeTextView;
-        @BindView(R.id.comment_markdown_view_item_post_comment) MarkwonView commentMarkdownView;
+        @BindView(R.id.comment_markdown_view_item_post_comment) CustomMarkwonView commentMarkdownView;
         @BindView(R.id.plus_button_item_post_comment) ImageView upvoteButton;
         @BindView(R.id.score_text_view_item_post_comment) TextView scoreTextView;
         @BindView(R.id.minus_button_item_post_comment) ImageView downvoteButton;
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/JSONUtils.java b/app/src/main/java/ml/docilealligator/infinityforreddit/JSONUtils.java
index 3feda5cf..7f92697a 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/JSONUtils.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/JSONUtils.java
@@ -76,4 +76,7 @@ public class JSONUtils {
     static final String VALUE_KEY = "value";
     static final String TEXT_KEY = "text";
     static final String SPOILER_KEY = "spoiler";
+    static final String RULES_KEY = "rules";
+    static final String SHORT_NAME_KEY = "short_name";
+    static final String DESCRIPTION_HTML_KEY = "description_html";
 }
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/PostImageActivity.java b/app/src/main/java/ml/docilealligator/infinityforreddit/PostImageActivity.java
index 1ba869c3..0d8a258c 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/PostImageActivity.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/PostImageActivity.java
@@ -179,6 +179,20 @@ public class PostImageActivity extends AppCompatActivity implements FlairBottomS
             startActivityForResult(intent, SUBREDDIT_SELECTION_REQUEST_CODE);
         });
 
+        rulesButton.setOnClickListener(view -> {
+            if(subredditName == null) {
+                Snackbar.make(coordinatorLayout, R.string.select_a_subreddit, Snackbar.LENGTH_SHORT).show();
+            } else {
+                Intent intent = new Intent(this, RulesActivity.class);
+                if(subredditIsUser) {
+                    intent.putExtra(RulesActivity.EXTRA_SUBREDDIT_NAME, "u_" + subredditName);
+                } else {
+                    intent.putExtra(RulesActivity.EXTRA_SUBREDDIT_NAME, subredditName);
+                }
+                startActivity(intent);
+            }
+        });
+
         flairTextView.setOnClickListener(view -> {
             if(flair == null) {
                 flairSelectionBottomSheetFragment = new FlairBottomSheetFragment();
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/PostLinkActivity.java b/app/src/main/java/ml/docilealligator/infinityforreddit/PostLinkActivity.java
index 7260c5af..c0067e88 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/PostLinkActivity.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/PostLinkActivity.java
@@ -150,6 +150,20 @@ public class PostLinkActivity extends AppCompatActivity implements FlairBottomSh
             startActivityForResult(intent, SUBREDDIT_SELECTION_REQUEST_CODE);
         });
 
+        rulesButton.setOnClickListener(view -> {
+            if(subredditName == null) {
+                Snackbar.make(coordinatorLayout, R.string.select_a_subreddit, Snackbar.LENGTH_SHORT).show();
+            } else {
+                Intent intent = new Intent(this, RulesActivity.class);
+                if(subredditIsUser) {
+                    intent.putExtra(RulesActivity.EXTRA_SUBREDDIT_NAME, "u_" + subredditName);
+                } else {
+                    intent.putExtra(RulesActivity.EXTRA_SUBREDDIT_NAME, subredditName);
+                }
+                startActivity(intent);
+            }
+        });
+
         flairTextView.setOnClickListener(view -> {
             if(flair == null) {
                 flairSelectionBottomSheetFragment = new FlairBottomSheetFragment();
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/PostTextActivity.java b/app/src/main/java/ml/docilealligator/infinityforreddit/PostTextActivity.java
index c943e88e..828f556c 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/PostTextActivity.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/PostTextActivity.java
@@ -151,6 +151,20 @@ public class PostTextActivity extends AppCompatActivity implements FlairBottomSh
             startActivityForResult(intent, SUBREDDIT_SELECTION_REQUEST_CODE);
         });
 
+        rulesButton.setOnClickListener(view -> {
+            if(subredditName == null) {
+                Snackbar.make(coordinatorLayout, R.string.select_a_subreddit, Snackbar.LENGTH_SHORT).show();
+            } else {
+                Intent intent = new Intent(this, RulesActivity.class);
+                if(subredditIsUser) {
+                    intent.putExtra(RulesActivity.EXTRA_SUBREDDIT_NAME, "u_" + subredditName);
+                } else {
+                    intent.putExtra(RulesActivity.EXTRA_SUBREDDIT_NAME, subredditName);
+                }
+                startActivity(intent);
+            }
+        });
+
         flairTextView.setOnClickListener(view -> {
             if(flair == null) {
                 flairSelectionBottomSheetFragment = new FlairBottomSheetFragment();
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/PostVideoActivity.java b/app/src/main/java/ml/docilealligator/infinityforreddit/PostVideoActivity.java
index 7432a0b7..23214037 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/PostVideoActivity.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/PostVideoActivity.java
@@ -184,6 +184,20 @@ public class PostVideoActivity extends AppCompatActivity implements FlairBottomS
             startActivityForResult(intent, SUBREDDIT_SELECTION_REQUEST_CODE);
         });
 
+        rulesButton.setOnClickListener(view -> {
+            if(subredditName == null) {
+                Snackbar.make(coordinatorLayout, R.string.select_a_subreddit, Snackbar.LENGTH_SHORT).show();
+            } else {
+                Intent intent = new Intent(this, RulesActivity.class);
+                if(subredditIsUser) {
+                    intent.putExtra(RulesActivity.EXTRA_SUBREDDIT_NAME, "u_" + subredditName);
+                } else {
+                    intent.putExtra(RulesActivity.EXTRA_SUBREDDIT_NAME, subredditName);
+                }
+                startActivity(intent);
+            }
+        });
+
         flairTextView.setOnClickListener(view -> {
             if(flair == null) {
                 flairSelectionBottomSheetFragment = new FlairBottomSheetFragment();
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/RedditAPI.java b/app/src/main/java/ml/docilealligator/infinityforreddit/RedditAPI.java
index b4dc3d97..75e99f7e 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/RedditAPI.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/RedditAPI.java
@@ -95,6 +95,9 @@ public interface RedditAPI {
     @GET("r/{subredditName}/api/link_flair.json?raw_json=1")
     Call<String> getFlairs(@HeaderMap Map<String, String> headers, @Path("subredditName") String subredditName);
 
+    @GET("/r/{subredditName}/about/rules.json?raw_json=1")
+    Call<String> getRules(@Path("subredditName") String subredditName);
+
     @Multipart
     @POST(".")
     Call<String> uploadMediaToAWS(@PartMap()Map<String, RequestBody> params, @Part() MultipartBody.Part file);
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/Rule.java b/app/src/main/java/ml/docilealligator/infinityforreddit/Rule.java
new file mode 100644
index 00000000..89b4d26d
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/Rule.java
@@ -0,0 +1,19 @@
+package ml.docilealligator.infinityforreddit;
+
+class Rule {
+    private String shortName;
+    private String descriptionHtml;
+
+    Rule(String shortName, String descriptionHtml) {
+        this.shortName = shortName;
+        this.descriptionHtml = descriptionHtml;
+    }
+
+    String getShortName() {
+        return shortName;
+    }
+
+    String getDescriptionHtml() {
+        return descriptionHtml;
+    }
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/RulesActivity.java b/app/src/main/java/ml/docilealligator/infinityforreddit/RulesActivity.java
new file mode 100644
index 00000000..18584546
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/RulesActivity.java
@@ -0,0 +1,170 @@
+package ml.docilealligator.infinityforreddit;
+
+import android.graphics.drawable.Drawable;
+import android.os.AsyncTask;
+import android.os.Bundle;
+import android.view.MenuItem;
+import android.view.View;
+import android.widget.ProgressBar;
+import android.widget.TextView;
+
+import androidx.annotation.NonNull;
+import androidx.appcompat.app.ActionBar;
+import androidx.appcompat.app.AppCompatActivity;
+import androidx.recyclerview.widget.LinearLayoutManager;
+import androidx.recyclerview.widget.RecyclerView;
+
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import java.util.ArrayList;
+
+import javax.inject.Inject;
+import javax.inject.Named;
+
+import butterknife.BindView;
+import butterknife.ButterKnife;
+import retrofit2.Call;
+import retrofit2.Callback;
+import retrofit2.Response;
+import retrofit2.Retrofit;
+
+public class RulesActivity extends AppCompatActivity {
+
+    static final String EXTRA_SUBREDDIT_NAME = "ESN";
+
+    @BindView(R.id.progress_bar_rules_activity) ProgressBar progressBar;
+    @BindView(R.id.recycler_view_rules_activity) RecyclerView recyclerView;
+    @BindView(R.id.error_text_view_rules_activity) TextView errorTextView;
+
+    private String mSubredditName;
+
+    private RulesRecyclerViewAdapter mAdapter;
+
+    @Inject
+    @Named("no_oauth")
+    Retrofit mRetrofit;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_rules);
+
+        ButterKnife.bind(this);
+
+        ((Infinity) getApplication()).getmAppComponent().inject(this);
+
+        ActionBar actionBar = getSupportActionBar();
+        Drawable upArrow = getResources().getDrawable(R.drawable.ic_arrow_back_white_24dp);
+        actionBar.setHomeAsUpIndicator(upArrow);
+
+        mSubredditName = getIntent().getExtras().getString(EXTRA_SUBREDDIT_NAME);
+
+        recyclerView.setLayoutManager(new LinearLayoutManager(this));
+        mAdapter = new RulesRecyclerViewAdapter(this);
+        recyclerView.setAdapter(mAdapter);
+
+        fetchRules();
+    }
+
+    private void fetchRules() {
+        progressBar.setVisibility(View.VISIBLE);
+        errorTextView.setVisibility(View.GONE);
+
+        RedditAPI api = mRetrofit.create(RedditAPI.class);
+        Call<String> rulesCall = api.getRules(mSubredditName);
+        rulesCall.enqueue(new Callback<String>() {
+            @Override
+            public void onResponse(@NonNull Call<String> call, @NonNull Response<String> response) {
+                if(response.isSuccessful()) {
+                    new ParseRulesAsyncTask(response.body(), new ParseRulesAsyncTask.ParseRulesAsyncTaskListener() {
+                        @Override
+                        public void parseSuccessful(ArrayList<Rule> rules) {
+                            progressBar.setVisibility(View.GONE);
+                            if(rules == null || rules.size() == 0) {
+                                errorTextView.setVisibility(View.VISIBLE);
+                                errorTextView.setText(R.string.no_rule);
+                                errorTextView.setOnClickListener(view -> {});
+                            }
+                            mAdapter.changeDataset(rules);
+                        }
+
+                        @Override
+                        public void parseFailed() {
+                            displayError();
+                        }
+                    }).execute();
+                } else {
+                    displayError();
+                }
+            }
+
+            @Override
+            public void onFailure(@NonNull Call<String> call, @NonNull Throwable t) {
+                displayError();
+            }
+        });
+    }
+
+    private void displayError() {
+        progressBar.setVisibility(View.GONE);
+        errorTextView.setVisibility(View.VISIBLE);
+        errorTextView.setText(R.string.error_loading_rules);
+        errorTextView.setOnClickListener(view -> fetchRules());
+    }
+
+    @Override
+    public boolean onOptionsItemSelected(@NonNull MenuItem item) {
+        if(item.getItemId() == android.R.id.home) {
+            finish();
+            return true;
+        }
+
+        return false;
+    }
+
+    private static class ParseRulesAsyncTask extends AsyncTask<Void, ArrayList<Rule>, ArrayList<Rule>> {
+        private String response;
+        private ParseRulesAsyncTaskListener parseRulesAsyncTaskListener;
+
+        interface ParseRulesAsyncTaskListener {
+            void parseSuccessful(ArrayList<Rule> rules);
+            void parseFailed();
+        }
+
+        ParseRulesAsyncTask(String response, ParseRulesAsyncTaskListener parseRulesAsyncTaskListener) {
+            this.response = response;
+            this.parseRulesAsyncTaskListener = parseRulesAsyncTaskListener;
+        }
+
+        @Override
+        protected ArrayList<Rule> doInBackground(Void... voids) {
+            try {
+                JSONArray rulesArray = new JSONObject(response).getJSONArray(JSONUtils.RULES_KEY);
+                ArrayList<Rule> rules = new ArrayList<>();
+                for(int i = 0; i < rulesArray.length(); i++) {
+                    String shortName = rulesArray.getJSONObject(i).getString(JSONUtils.SHORT_NAME_KEY);
+                    String descriptionHtml = null;
+                    if(rulesArray.getJSONObject(i).has(JSONUtils.DESCRIPTION_HTML_KEY)) {
+                        descriptionHtml = rulesArray.getJSONObject(i).getString(JSONUtils.DESCRIPTION_HTML_KEY);
+                    }
+                    rules.add(new Rule(shortName, descriptionHtml));
+                }
+                return rules;
+            } catch (JSONException e) {
+                e.printStackTrace();
+            }
+            return null;
+        }
+
+        @Override
+        protected void onPostExecute(ArrayList<Rule> rules) {
+            if(rules != null) {
+                parseRulesAsyncTaskListener.parseSuccessful(rules);
+            } else {
+                parseRulesAsyncTaskListener.parseFailed();
+            }
+        }
+    }
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/RulesRecyclerViewAdapter.java b/app/src/main/java/ml/docilealligator/infinityforreddit/RulesRecyclerViewAdapter.java
new file mode 100644
index 00000000..941b0316
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/RulesRecyclerViewAdapter.java
@@ -0,0 +1,67 @@
+package ml.docilealligator.infinityforreddit;
+
+import android.content.Context;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.TextView;
+
+import androidx.annotation.NonNull;
+import androidx.recyclerview.widget.RecyclerView;
+
+import java.util.ArrayList;
+
+import CustomView.CustomMarkwonView;
+import butterknife.BindView;
+import butterknife.ButterKnife;
+
+class RulesRecyclerViewAdapter extends RecyclerView.Adapter<RulesRecyclerViewAdapter.RuleViewHolder> {
+    private Context context;
+    private ArrayList<Rule> rules;
+
+    RulesRecyclerViewAdapter(Context context) {
+        this.context = context;
+    }
+
+    @NonNull
+    @Override
+    public RuleViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
+        return new RuleViewHolder(LayoutInflater.from(parent.getContext()).inflate(R.layout.item_rule, parent, false));
+    }
+
+    @Override
+    public void onBindViewHolder(@NonNull RuleViewHolder holder, int position) {
+        holder.shortNameTextView.setText(rules.get(holder.getAdapterPosition()).getShortName());
+        if(rules.get(holder.getAdapterPosition()).getDescriptionHtml() == null) {
+            holder.descriptionMarkwonView.setVisibility(View.GONE);
+        } else {
+            holder.descriptionMarkwonView.setMarkdown(rules.get(holder.getAdapterPosition()).getDescriptionHtml(), context);
+        }
+    }
+
+    @Override
+    public int getItemCount() {
+        return rules == null ? 0 : rules.size();
+    }
+
+    @Override
+    public void onViewRecycled(@NonNull RuleViewHolder holder) {
+        super.onViewRecycled(holder);
+        holder.descriptionMarkwonView.setVisibility(View.VISIBLE);
+    }
+
+    void changeDataset(ArrayList<Rule> rules) {
+        this.rules = rules;
+        notifyDataSetChanged();
+    }
+
+    class RuleViewHolder extends RecyclerView.ViewHolder {
+        @BindView(R.id.short_name_text_view_item_rule) TextView shortNameTextView;
+        @BindView(R.id.description_markwon_view_item_rule) CustomMarkwonView descriptionMarkwonView;
+
+        RuleViewHolder(@NonNull View itemView) {
+            super(itemView);
+            ButterKnife.bind(this, itemView);
+        }
+    }
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/ViewPostDetailActivity.java b/app/src/main/java/ml/docilealligator/infinityforreddit/ViewPostDetailActivity.java
index 9b8529ed..f605666c 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/ViewPostDetailActivity.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/ViewPostDetailActivity.java
@@ -65,7 +65,7 @@ public class ViewPostDetailActivity extends AppCompatActivity {
     private boolean hasMoreChildren;
 
     private LinearLayoutManager mLinearLayoutManager;
-    private CommentRecyclerViewAdapter mAdapter;
+    private CommentAndPostRecyclerViewAdapter mAdapter;
     private LoadSubredditIconAsyncTask mLoadSubredditIconAsyncTask;
 
     @BindView(R.id.coordinator_layout_view_post_detail) CoordinatorLayout mCoordinatorLayout;
@@ -109,10 +109,10 @@ public class ViewPostDetailActivity extends AppCompatActivity {
             mPost = savedInstanceState.getParcelable(POST_STATE);
         }
 
-        mAdapter = new CommentRecyclerViewAdapter(ViewPostDetailActivity.this, mRetrofit,
+        mAdapter = new CommentAndPostRecyclerViewAdapter(ViewPostDetailActivity.this, mRetrofit,
                 mOauthRetrofit, mGlide, mSharedPreferences, mPost,
                 mPost.getSubredditNamePrefixed(), mLocale, mLoadSubredditIconAsyncTask,
-                new CommentRecyclerViewAdapter.CommentRecyclerViewAdapterCallback() {
+                new CommentAndPostRecyclerViewAdapter.CommentRecyclerViewAdapterCallback() {
                     @Override
                     public void updatePost(Post post) {
                         EventBus.getDefault().post(new PostUpdateEventToPostList(mPost, postListPosition));
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/ViewSubredditDetailActivity.java b/app/src/main/java/ml/docilealligator/infinityforreddit/ViewSubredditDetailActivity.java
index 3433cfb8..5bc0c163 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/ViewSubredditDetailActivity.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/ViewSubredditDetailActivity.java
@@ -45,7 +45,7 @@ import retrofit2.Retrofit;
 
 public class ViewSubredditDetailActivity extends AppCompatActivity {
 
-    static final String EXTRA_SUBREDDIT_NAME_KEY = "ESN";
+    public static final String EXTRA_SUBREDDIT_NAME_KEY = "ESN";
 
     private static final String FRAGMENT_OUT_STATE_KEY = "FOSK";
     private static final String IS_IN_LAZY_MODE_STATE = "IILMS";
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/ViewUserDetailActivity.java b/app/src/main/java/ml/docilealligator/infinityforreddit/ViewUserDetailActivity.java
index e9ab3123..64d7cdc2 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/ViewUserDetailActivity.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/ViewUserDetailActivity.java
@@ -42,7 +42,7 @@ import retrofit2.Retrofit;
 
 public class ViewUserDetailActivity extends AppCompatActivity {
 
-    static final String EXTRA_USER_NAME_KEY = "EUNK";
+    public static final String EXTRA_USER_NAME_KEY = "EUNK";
 
     private static final String FRAGMENT_OUT_STATE_KEY = "FOSK";
     private static final String IS_IN_LAZY_MODE_STATE = "IILMS";
diff --git a/app/src/main/res/layout/activity_rules.xml b/app/src/main/res/layout/activity_rules.xml
new file mode 100644
index 00000000..6678f13c
--- /dev/null
+++ b/app/src/main/res/layout/activity_rules.xml
@@ -0,0 +1,27 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.coordinatorlayout.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".RulesActivity">
+
+    <ProgressBar
+        android:id="@+id/progress_bar_rules_activity"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="center" />
+
+    <androidx.recyclerview.widget.RecyclerView
+        android:id="@+id/recycler_view_rules_activity"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent" />
+
+    <TextView
+        android:id="@+id/error_text_view_rules_activity"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:gravity="center"
+        android:visibility="gone" />
+
+</androidx.coordinatorlayout.widget.CoordinatorLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/item_comment.xml b/app/src/main/res/layout/item_comment.xml
index 088943f7..d03b0bad 100644
--- a/app/src/main/res/layout/item_comment.xml
+++ b/app/src/main/res/layout/item_comment.xml
@@ -42,7 +42,7 @@
 
             </LinearLayout>
 
-            <ru.noties.markwon.view.MarkwonView
+            <CustomView.CustomMarkwonView
                 android:id="@+id/comment_markdown_view_item_post_comment"
                 android:layout_width="match_parent"
                 android:layout_height="wrap_content"
diff --git a/app/src/main/res/layout/item_post_detail.xml b/app/src/main/res/layout/item_post_detail.xml
index babdcdbf..fc48202e 100644
--- a/app/src/main/res/layout/item_post_detail.xml
+++ b/app/src/main/res/layout/item_post_detail.xml
@@ -63,7 +63,7 @@
             android:textColor="@color/primaryTextColor"
             android:textSize="18sp" />
 
-        <ru.noties.markwon.view.MarkwonView
+        <CustomView.CustomMarkwonView
             android:id="@+id/content_markdown_view_item_post_detail"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
diff --git a/app/src/main/res/layout/item_rule.xml b/app/src/main/res/layout/item_rule.xml
new file mode 100644
index 00000000..1124a548
--- /dev/null
+++ b/app/src/main/res/layout/item_rule.xml
@@ -0,0 +1,22 @@
+<?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">
+
+    <TextView
+        android:id="@+id/short_name_text_view_item_rule"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:padding="16dp"
+        android:textColor="@color/primaryTextColor"
+        android:textSize="16sp" />
+
+    <CustomView.CustomMarkwonView
+        android:id="@+id/description_markwon_view_item_rule"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:paddingBottom="16dp"
+        android:paddingStart="16dp"
+        android:paddingEnd="16dp" />
+
+</LinearLayout>
\ No newline at end of file
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index d76df6b2..005aa048 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -9,6 +9,7 @@
     <string name="post_link_activity_label">Link Post</string>
     <string name="post_image_activity_label">Image Post</string>
     <string name="post_video_activity_label">Video Post</string>
+    <string name="rules_activity_label">Rules</string>
 
     <string name="navigation_drawer_open">Open navigation drawer</string>
     <string name="navigation_drawer_close">Close navigation drawer</string>
@@ -124,4 +125,7 @@
 
     <string name="no_flair">No flair</string>
     <string name="error_loading_flairs">Error loading flairs.\nTap to retry.</string>
+
+    <string name="no_rule">No rule</string>
+    <string name="error_loading_rules">Error loading rules.\nTap to retry.</string>
 </resources>