Implement Deep Link to open reddit links directly in this app.

app/src/main/AndroidManifest.xml

@@ -73,7 +73,6 @@
             android:theme="@style/AppTheme.NoActionBarWithTransparentStatusBar">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
-
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
         </activity>
@@ -92,15 +91,42 @@
         <activity
             android:name=".ViewPostDetailActivity"
             android:parentActivityName=".MainActivity"
-            android:theme="@style/AppTheme.NoActionBar" />
+            android:theme="@style/AppTheme.NoActionBar">
+            <intent-filter>
+                <action android:name="android.intent.action.VIEW" />
+                <category android:name="android.intent.category.DEFAULT" />
+                <category android:name="android.intent.category.BROWSABLE" />
+                <data android:scheme="https"
+                    android:host="www.reddit.com"
+                    android:pathPattern="/r/..*/comments/..*"/>
+            </intent-filter>
+        </activity>
         <activity
             android:name=".ViewSubredditDetailActivity"
             android:parentActivityName=".MainActivity"
-            android:theme="@style/AppTheme.NoActionBarWithTranslucentWindow" />
+            android:theme="@style/AppTheme.NoActionBarWithTranslucentWindow">
+            <intent-filter>
+                <action android:name="android.intent.action.VIEW" />
+                <category android:name="android.intent.category.DEFAULT" />
+                <category android:name="android.intent.category.BROWSABLE" />
+                <data android:scheme="https"
+                    android:host="www.reddit.com"
+                    android:pathPattern="/r/..*"/>
+            </intent-filter>
+        </activity>
         <activity
             android:name=".ViewUserDetailActivity"
             android:parentActivityName=".MainActivity"
-            android:theme="@style/AppTheme.NoActionBarWithTranslucentWindow" />
+            android:theme="@style/AppTheme.NoActionBarWithTranslucentWindow">
+            <intent-filter>
+                <action android:name="android.intent.action.VIEW" />
+                <category android:name="android.intent.category.DEFAULT" />
+                <category android:name="android.intent.category.BROWSABLE" />
+                <data android:scheme="https"
+                    android:host="www.reddit.com"
+                    android:pathPattern="/user/..*"/>
+            </intent-filter>
+        </activity>
 
         <provider
             android:name="androidx.core.content.FileProvider"

app/src/main/java/ml/docilealligator/infinityforreddit/MainActivity.java

@@ -44,6 +44,8 @@ import retrofit2.Retrofit;
 public class MainActivity extends AppCompatActivity implements SortTypeBottomSheetFragment.SortTypeSelectionCallback,
         PostTypeBottomSheetFragment.PostTypeSelectionCallback {
 
+    static final String EXTRA_POST_TYPE = "EPT";
+
     private static final String FETCH_USER_INFO_STATE = "FUIS";
     private static final String IS_IN_LAZY_MODE_STATE = "IILMS";
 
@@ -138,6 +140,14 @@ public class MainActivity extends AppCompatActivity implements SortTypeBottomShe
             if (savedInstanceState != null) {
                 mFetchUserInfoSuccess = savedInstanceState.getBoolean(FETCH_USER_INFO_STATE);
                 isInLazyMode = savedInstanceState.getBoolean(IS_IN_LAZY_MODE_STATE);
+            } else {
+                if(getIntent().hasExtra(EXTRA_POST_TYPE)) {
+                    if(getIntent().getExtras().getString(EXTRA_POST_TYPE).equals("popular")) {
+                        viewPager.setCurrentItem(1);
+                    } else {
+                        viewPager.setCurrentItem(2);
+                    }
+                }
             }
 
             glide = Glide.with(this);

app/src/main/java/ml/docilealligator/infinityforreddit/ViewPostDetailActivity.java

@@ -3,6 +3,7 @@ package ml.docilealligator.infinityforreddit;
 import android.content.Context;
 import android.content.Intent;
 import android.content.SharedPreferences;
+import android.net.Uri;
 import android.os.Bundle;
 import android.util.Log;
 import android.view.Menu;
@@ -32,6 +33,7 @@ import org.greenrobot.eventbus.EventBus;
 import org.greenrobot.eventbus.Subscribe;
 
 import java.util.ArrayList;
+import java.util.List;
 import java.util.Locale;
 
 import javax.inject.Inject;
@@ -62,6 +64,8 @@ public class ViewPostDetailActivity extends AppCompatActivity {
     @State
     Post mPost;
     @State
+    Uri postUri;
+    @State
     boolean isLoadingMoreChildren = false;
     @State
     boolean isRefreshing = false;
@@ -122,13 +126,17 @@ public class ViewPostDetailActivity extends AppCompatActivity {
         orientation = getResources().getConfiguration().orientation;
 
         if(mPost == null) {
-            mPost = getIntent().getExtras().getParcelable(EXTRA_POST_DATA);
+            if(getIntent().getData() != null) {
+                postUri = getIntent().getData();
+            } else {
+                mPost = getIntent().getExtras().getParcelable(EXTRA_POST_DATA);
+            }
         }
 
-        if(mPost == null) {
+        if(postUri == null && mPost == null) {
             mProgressBar.setVisibility(View.VISIBLE);
             fetchPostAndCommentsById(getIntent().getExtras().getString(EXTRA_POST_ID));
-        } else {
+        } else if(mPost != null) {
             mAdapter = new CommentAndPostRecyclerViewAdapter(ViewPostDetailActivity.this, mRetrofit,
                     mOauthRetrofit, mGlide, mSharedPreferences, mPost,
                     mPost.getSubredditNamePrefixed(), mLocale, mLoadSubredditIconAsyncTask,
@@ -162,6 +170,17 @@ public class ViewPostDetailActivity extends AppCompatActivity {
                     }
                 }
             }
+        } else {
+            mProgressBar.setVisibility(View.VISIBLE);
+            List<String> segments = postUri.getPathSegments();
+            int commentIndex = segments.indexOf("comments");
+            if(commentIndex >= 0 || commentIndex != segments.size() - 1) {
+                mProgressBar.setVisibility(View.VISIBLE);
+                fetchPostAndCommentsById(segments.get(commentIndex + 1));
+            } else {
+                //Deep link error handling
+                finish();
+            }
         }
 
         if(getIntent().hasExtra(EXTRA_POST_LIST_POSITION)) {

app/src/main/java/ml/docilealligator/infinityforreddit/ViewSubredditDetailActivity.java

@@ -2,6 +2,7 @@ package ml.docilealligator.infinityforreddit;
 
 import android.content.Intent;
 import android.content.SharedPreferences;
+import android.net.Uri;
 import android.os.AsyncTask;
 import android.os.Bundle;
 import android.view.Menu;
@@ -26,6 +27,8 @@ import com.google.android.material.chip.Chip;
 import com.google.android.material.floatingactionbutton.FloatingActionButton;
 import com.google.android.material.snackbar.Snackbar;
 
+import java.util.List;
+
 import javax.inject.Inject;
 import javax.inject.Named;
 
@@ -63,6 +66,7 @@ public class ViewSubredditDetailActivity extends AppCompatActivity implements So
     @BindView(R.id.fab_view_subreddit_detail_activity) FloatingActionButton fab;
 
     private String subredditName;
+    private Uri subredditUri;
     private boolean subscriptionReady = false;
     private boolean isInLazyMode = false;
 
@@ -113,7 +117,26 @@ public class ViewSubredditDetailActivity extends AppCompatActivity implements So
             statusBarHeight = getResources().getDimensionPixelSize(resourceId);
         }
 
-        subredditName = getIntent().getExtras().getString(EXTRA_SUBREDDIT_NAME_KEY);
+        if(getIntent().getData() != null) {
+            subredditUri = getIntent().getData();
+            List<String> segments = subredditUri.getPathSegments();
+            int rIndex = segments.indexOf("r");
+            if(rIndex >= 0 && rIndex < segments.size() - 1) {
+                subredditName = segments.get(rIndex + 1);
+                if(subredditName.equals("popular") || subredditName.equals("all")) {
+                    Intent intent = new Intent(this, MainActivity.class);
+                    intent.putExtra(MainActivity.EXTRA_POST_TYPE, subredditName);
+                    startActivity(intent);
+                    finish();
+                }
+            } else {
+                //Deep link error handling
+                finish();
+            }
+        } else {
+            subredditName = getIntent().getExtras().getString(EXTRA_SUBREDDIT_NAME_KEY);
+        }
+
         String title = "r/" + subredditName;
         subredditNameTextView.setText(title);
 

app/src/main/java/ml/docilealligator/infinityforreddit/ViewUserDetailActivity.java

@@ -2,6 +2,7 @@ package ml.docilealligator.infinityforreddit;
 
 import android.content.Intent;
 import android.content.SharedPreferences;
+import android.net.Uri;
 import android.os.AsyncTask;
 import android.os.Bundle;
 import android.view.Menu;
@@ -29,6 +30,8 @@ import com.google.android.material.chip.Chip;
 import com.google.android.material.snackbar.Snackbar;
 import com.google.android.material.tabs.TabLayout;
 
+import java.util.List;
+
 import javax.inject.Inject;
 import javax.inject.Named;
 
@@ -71,6 +74,7 @@ public class ViewUserDetailActivity extends AppCompatActivity {
     private AppBarLayout.LayoutParams params;
 
     private String userName;
+    private Uri userUri;
     private boolean subscriptionReady = false;
     private boolean isInLazyMode = false;
     private int colorPrimary;
@@ -106,7 +110,20 @@ public class ViewUserDetailActivity extends AppCompatActivity {
             statusBarHeight = getResources().getDimensionPixelSize(resourceId);
         }
 
-        userName = getIntent().getExtras().getString(EXTRA_USER_NAME_KEY);
+        if(getIntent().getData() != null) {
+            userUri = getIntent().getData();
+            List<String> segments = userUri.getPathSegments();
+            int userIndex = segments.indexOf("user");
+            if(userIndex >= 0 && userIndex < segments.size() - 1) {
+                userName = segments.get(userIndex + 1);
+            } else {
+                //Deep link error handling
+                finish();
+            }
+        } else {
+            userName = getIntent().getExtras().getString(EXTRA_USER_NAME_KEY);
+        }
+
         String title = "u/" + userName;
         userNameTextView.setText(title);