Fix lint warnings and improve code quality

app/src/main/AndroidManifest.xml

@@ -9,7 +9,8 @@
         android:name="android.permission.MANAGE_EXTERNAL_STORAGE"
         tools:ignore="scopedStorage" />
 
-    <uses-feature android:name="android.hardware.camera" />
+    <uses-feature android:name="android.hardware.camera"
+        android:required="false" />
     <uses-feature
         android:name="android.hardware.camera.autofocus"
         android:required="false" />
@@ -27,7 +28,8 @@
         android:requestLegacyExternalStorage="true"
         android:supportsRtl="true"
         android:theme="@style/AppThemeWhite"
-        tools:ignore="GoogleAppIndexingWarning,RtlEnabled">
+        tools:ignore="GoogleAppIndexingWarning,RtlEnabled"
+        android:dataExtractionRules="@xml/data_extraction_rules">
         <activity
             android:name=".activity.SplashActivity"
             android:exported="true"
@@ -44,8 +46,7 @@
             android:theme="@style/Base.Theme.AppCompat" />
         <activity
             android:name=".activity.MainActivity"
-            android:label="@string/app_name"
-            android:screenOrientation="portrait"
+            android:screenOrientation="fullSensor"
             android:windowSoftInputMode="adjustPan"
             android:exported="false">
             <intent-filter>

app/src/main/java/swati4star/createpdf/activity/CropImageActivity.java

@@ -14,6 +14,7 @@
 import android.widget.ImageView;
 import android.widget.TextView;
 
+import androidx.annotation.NonNull;
 import androidx.appcompat.app.AppCompatActivity;
 
 import com.google.android.material.appbar.MaterialToolbar;
@@ -41,7 +42,7 @@ public class CropImageActivity extends AppCompatActivity {
     private CropImageView mCropImageView;
 
     @Override
-    public void onCreate(Bundle savedInstanceState) {
+    public void onCreate(@NonNull Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_crop_image_activity);
         ButterKnife.bind(this);
@@ -138,7 +139,7 @@ public boolean onCreateOptionsMenu(Menu menu) {
     }
 
     @Override
-    public boolean onOptionsItemSelected(MenuItem item) {
+    public boolean onOptionsItemSelected(@NonNull MenuItem item) {
         if (item.getItemId() == android.R.id.home) {
             setResult(Activity.RESULT_CANCELED);
             finish();

app/src/main/java/swati4star/createpdf/activity/FavouritesActivity.java

@@ -27,6 +27,7 @@
 import android.view.Menu;
 import android.view.MenuItem;
 
+import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.appcompat.app.AppCompatActivity;
 import androidx.appcompat.widget.Toolbar;
@@ -65,7 +66,7 @@ public boolean onCreateOptionsMenu(Menu menu) {
     }
 
     @Override
-    public boolean onOptionsItemSelected(MenuItem item) {
+    public boolean onOptionsItemSelected(@NonNull MenuItem item) {
         switch (item.getItemId()) {
             case android.R.id.home:
                 onBackPressed();

app/src/main/java/swati4star/createpdf/activity/ImageEditor.java

@@ -71,14 +71,15 @@ public class ImageEditor extends AppCompatActivity implements OnFilterItemClicke
     private boolean mDoodleSelected = false;
     private PhotoEditor mPhotoEditor;
 
-    public static Intent getStartIntent(Context context, ArrayList<String> uris) {
+    @NonNull
+    public static Intent getStartIntent(@NonNull Context context, @NonNull ArrayList<String> uris) {
         Intent intent = new Intent(context, ImageEditor.class);
         intent.putExtra(IMAGE_EDITOR_KEY, uris);
         return intent;
     }
 
     @Override
-    protected void onCreate(Bundle savedInstanceState) {
+    protected void onCreate(@NonNull Bundle savedInstanceState) {
 
         ThemeUtils.getInstance().setThemeApp(this);
 
@@ -236,7 +237,7 @@ private void initRecyclerView() {
      * @param position - position of item clicked
      */
     @Override
-    public void onItemClick(View view, int position) {
+    public void onItemClick(@NonNull View view, int position) {
         //setting mClicked true when none filter is selected otherwise false
         mClicked = position == 0;
         // Brush effect is in second position

app/src/main/java/swati4star/createpdf/activity/ImagesPreviewActivity.java

@@ -6,6 +6,7 @@
 import android.content.Intent;
 import android.os.Bundle;
 
+import androidx.annotation.NonNull;
 import androidx.appcompat.app.AppCompatActivity;
 import androidx.viewpager.widget.ViewPager;
 
@@ -27,14 +28,15 @@ public class ImagesPreviewActivity extends AppCompatActivity {
      * @param uris    - extra images uri
      * @return - start intent
      */
-    public static Intent getStartIntent(Context context, ArrayList<String> uris) {
+    @NonNull
+    public static Intent getStartIntent(@NonNull Context context, @NonNull ArrayList<String> uris) {
         Intent intent = new Intent(context, ImagesPreviewActivity.class);
         intent.putExtra(PREVIEW_IMAGES, uris);
         return intent;
     }
 
     @Override
-    protected void onCreate(Bundle savedInstanceState) {
+    protected void onCreate(@NonNull Bundle savedInstanceState) {
         ThemeUtils.getInstance().setThemeApp(this);
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_preview_images);

app/src/main/java/swati4star/createpdf/activity/MainActivity.java

@@ -61,7 +61,7 @@ public class MainActivity extends AppCompatActivity
     private FragmentManagement mFragmentManagement;
 
     @Override
-    protected void onCreate(Bundle savedInstanceState) {
+    protected void onCreate(@NonNull Bundle savedInstanceState) {
         ThemeUtils.getInstance().setThemeApp(this);
         super.onCreate(savedInstanceState);
 
@@ -145,7 +145,7 @@ public boolean onCreateOptionsMenu(Menu menu) {
     }
 
     @Override
-    public boolean onOptionsItemSelected(MenuItem item) {
+    public boolean onOptionsItemSelected(@NonNull MenuItem item) {
         if (item.getItemId() == R.id.menu_favourites_item) {
             setTitle(R.string.favourites);
             mFragmentManagement.favouritesFragmentOption();
@@ -375,7 +375,7 @@ public void onNeutralButtonClick() {
      *
      * @param imageUris - ArrayList of image uri's in temp directory
      */
-    public void convertImagesToPdf(ArrayList<Uri> imageUris) {
+    public void convertImagesToPdf(@NonNull ArrayList<Uri> imageUris) {
         Fragment fragment = new ImageToPdfFragment();
         Bundle bundle = new Bundle();
         bundle.putParcelableArrayList(getString(R.string.bundleKey), imageUris);

app/src/main/java/swati4star/createpdf/activity/PreviewActivity.java

@@ -7,6 +7,7 @@
 import android.content.Intent;
 import android.os.Bundle;
 
+import androidx.annotation.NonNull;
 import androidx.appcompat.app.AppCompatActivity;
 import androidx.recyclerview.widget.LinearLayoutManager;
 import androidx.recyclerview.widget.RecyclerView;
@@ -36,14 +37,15 @@ public class PreviewActivity extends AppCompatActivity implements PreviewImageOp
     private PreviewAdapter mPreviewAdapter;
     private ViewPager mViewPager;
 
-    public static Intent getStartIntent(Context context, ArrayList<String> uris) {
+    @NonNull
+    public static Intent getStartIntent(@NonNull Context context, @NonNull ArrayList<String> uris) {
         Intent intent = new Intent(context, PreviewActivity.class);
         intent.putExtra(PREVIEW_IMAGES, uris);
         return intent;
     }
 
     @Override
-    protected void onCreate(Bundle savedInstanceState) {
+    protected void onCreate(@NonNull Bundle savedInstanceState) {
 
         ThemeUtils.getInstance().setThemeApp(this);
         super.onCreate(savedInstanceState);

app/src/main/java/swati4star/createpdf/activity/RearrangeImages.java

@@ -11,6 +11,7 @@
 import android.preference.PreferenceManager;
 import android.view.MenuItem;
 
+import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.appcompat.app.AppCompatActivity;
 import androidx.appcompat.widget.Toolbar;
@@ -41,7 +42,8 @@ public class RearrangeImages extends AppCompatActivity implements RearrangeImage
     private RearrangeImagesAdapter mRearrangeImagesAdapter;
     private SharedPreferences mSharedPreferences;
 
-    public static Intent getStartIntent(Context context, ArrayList<String> uris) {
+    @NonNull
+    public static Intent getStartIntent(@NonNull Context context, @NonNull ArrayList<String> uris) {
         Intent intent = new Intent(context, RearrangeImages.class);
         intent.putExtra(PREVIEW_IMAGES, uris);
         return intent;
@@ -122,7 +124,7 @@ public void onBackPressed() {
     }
 
     @Override
-    public boolean onOptionsItemSelected(MenuItem item) {
+    public boolean onOptionsItemSelected(@NonNull MenuItem item) {
         if (item.getItemId() == android.R.id.home) {
             passUris();
             return true;

app/src/main/java/swati4star/createpdf/activity/RearrangePdfPages.java

@@ -15,6 +15,7 @@
 import android.view.View;
 import android.widget.Button;
 
+import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.appcompat.app.AppCompatActivity;
 import androidx.appcompat.widget.Toolbar;
@@ -36,6 +37,7 @@
 
 public class RearrangePdfPages extends AppCompatActivity implements RearrangePdfAdapter.OnClickListener {
 
+    @NonNull
     public static ArrayList<Bitmap> mImages;
     @BindView(R.id.recyclerView)
     RecyclerView mRecyclerView;
@@ -45,7 +47,8 @@ public class RearrangePdfPages extends AppCompatActivity implements RearrangePdf
     private SharedPreferences mSharedPreferences;
     private ArrayList<Integer> mSequence, mInitialSequence;
 
-    public static Intent getStartIntent(Context context) {
+    @NonNull
+    public static Intent getStartIntent(@NonNull Context context) {
         return new Intent(context, RearrangePdfPages.class);
     }
 
@@ -155,7 +158,7 @@ public void onBackPressed() {
     }
 
     @Override
-    public boolean onOptionsItemSelected(MenuItem item) {
+    public boolean onOptionsItemSelected(@NonNull MenuItem item) {
         if (item.getItemId() == android.R.id.home) {
             passUris();
             return true;

app/src/main/java/swati4star/createpdf/activity/SplashActivity.java

@@ -3,12 +3,13 @@
 import android.content.Intent;
 import android.os.Bundle;
 
+import androidx.annotation.NonNull;
 import androidx.appcompat.app.AppCompatActivity;
 
 public class SplashActivity extends AppCompatActivity {
 
     @Override
-    protected void onCreate(Bundle savedInstanceState) {
+    protected void onCreate(@NonNull Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         startActivity(new Intent(SplashActivity.this, MainActivity.class));
         finish();

app/src/main/java/swati4star/createpdf/activity/WelcomeActivity.java

@@ -23,10 +23,13 @@
 
 public class WelcomeActivity extends AppCompatActivity {
 
+    @NonNull
     @BindView(R.id.view_pager)
     public ViewPager mViewPager;
+    @NonNull
     @BindView(R.id.layoutDots)
     public LinearLayout mDotsLayout;
+    @NonNull
     @BindView(R.id.btn_skip)
     public Button mBtnSkip;
 
@@ -51,7 +54,7 @@ public void onPageScrollStateChanged(int arg0) {
     };
 
     @Override
-    protected void onCreate(Bundle savedInstanceState) {
+    protected void onCreate(@NonNull Bundle savedInstanceState) {
         ThemeUtils.getInstance().setThemeApp(this);
         super.onCreate(savedInstanceState);
 

app/src/main/java/swati4star/createpdf/adapter/BrushItemAdapter.java

@@ -23,9 +23,9 @@ public class BrushItemAdapter extends RecyclerView.Adapter<BrushItemAdapter.Brus
     private final OnItemClickListener mOnItemClickListener;
     private final List<BrushItem> mBrushItems;
 
-    public BrushItemAdapter(Context context,
-                            OnItemClickListener onItemClickListener,
-                            List<BrushItem> brushItems) {
+    public BrushItemAdapter(@NonNull Context context,
+                            @NonNull OnItemClickListener onItemClickListener,
+                            @NonNull List<BrushItem> brushItems) {
         mBrushItems = brushItems;
         mOnItemClickListener = onItemClickListener;
         mContext = context;

app/src/main/java/swati4star/createpdf/adapter/EnhancementOptionsAdapter.java

@@ -25,8 +25,8 @@ public class EnhancementOptionsAdapter
     private final OnItemClickListener mOnItemClickListener;
     private final List<EnhancementOptionsEntity> mEnhancementOptionsEntityList;
 
-    public EnhancementOptionsAdapter(OnItemClickListener mOnItemClickListener,
-                                     List<EnhancementOptionsEntity> mEnhancementOptionsEntityList) {
+    public EnhancementOptionsAdapter(@NonNull OnItemClickListener mOnItemClickListener,
+                                     @NonNull List<EnhancementOptionsEntity> mEnhancementOptionsEntityList) {
         this.mOnItemClickListener = mOnItemClickListener;
         this.mEnhancementOptionsEntityList = mEnhancementOptionsEntityList;
     }

app/src/main/java/swati4star/createpdf/adapter/ExtractImagesAdapter.java

@@ -26,8 +26,8 @@ public class ExtractImagesAdapter extends RecyclerView.Adapter<ExtractImagesAdap
     private final Activity mContext;
     private final OnFileItemClickedListener mOnClickListener;
 
-    public ExtractImagesAdapter(Activity mContext, ArrayList<String> mFilePaths,
-                                OnFileItemClickedListener mOnClickListener) {
+    public ExtractImagesAdapter(@NonNull Activity mContext, @NonNull ArrayList<String> mFilePaths,
+                                @NonNull OnFileItemClickedListener mOnClickListener) {
         this.mContext = mContext;
         this.mFilePaths = mFilePaths;
         this.mOnClickListener = mOnClickListener;
@@ -55,7 +55,7 @@ public int getItemCount() {
     }
 
     public interface OnFileItemClickedListener {
-        void onFileItemClick(String path);
+        void onFileItemClick(@NonNull String path);
     }
 
     public class ViewMergeFilesHolder extends RecyclerView.ViewHolder implements View.OnClickListener {

app/src/main/java/swati4star/createpdf/adapter/FAQAdapter.java

@@ -22,7 +22,7 @@ public class FAQAdapter extends RecyclerView.Adapter<FAQAdapter.FAQViewHolder> {
     private final List<FAQItem> mFaqs;
     private final OnItemClickListener mOnItemClickListener;
 
-    public FAQAdapter(List<FAQItem> faqs, OnItemClickListener mOnItemClickListener) {
+    public FAQAdapter(@NonNull List<FAQItem> faqs, @NonNull OnItemClickListener mOnItemClickListener) {
         this.mFaqs = faqs;
         this.mOnItemClickListener = mOnItemClickListener;
     }

app/src/main/java/swati4star/createpdf/adapter/FilesListAdapter.java

@@ -23,8 +23,8 @@ public class FilesListAdapter extends RecyclerView.Adapter<FilesListAdapter.View
     private final Activity mContext;
     private final OnFileItemClickedListener mOnClickListener;
 
-    public FilesListAdapter(Activity mContext, ArrayList<String> mFilePaths,
-                            OnFileItemClickedListener mOnClickListener) {
+    public FilesListAdapter(@NonNull Activity mContext, @NonNull ArrayList<String> mFilePaths,
+                            @NonNull OnFileItemClickedListener mOnClickListener) {
         this.mContext = mContext;
         this.mFilePaths = mFilePaths;
         this.mOnClickListener = mOnClickListener;
@@ -50,7 +50,7 @@ public int getItemCount() {
     }
 
     public interface OnFileItemClickedListener {
-        void onFileItemClick(String path);
+        void onFileItemClick(@NonNull String path);
     }
 
     public class ViewMergeFilesHolder extends RecyclerView.ViewHolder implements View.OnClickListener {

app/src/main/java/swati4star/createpdf/adapter/HistoryAdapter.java

@@ -26,7 +26,7 @@ public class HistoryAdapter extends RecyclerView.Adapter<HistoryAdapter.ViewHist
     private final OnClickListener mOnClickListener;
     private final HashMap<String, Integer> mIconsOperationList;
 
-    public HistoryAdapter(Activity mActivity, List<History> mHistoryList, OnClickListener mOnClickListener) {
+    public HistoryAdapter(@NonNull Activity mActivity, @NonNull List<History> mHistoryList, @NonNull OnClickListener mOnClickListener) {
         this.mHistoryList = mHistoryList;
         this.mActivity = mActivity;
         this.mOnClickListener = mOnClickListener;
@@ -88,7 +88,7 @@ public int getItemCount() {
     }
 
     public interface OnClickListener {
-        void onItemClick(String path);
+        void onItemClick(@NonNull String path);
     }
 
     public class ViewHistoryHolder extends RecyclerView.ViewHolder implements View.OnClickListener {

app/src/main/java/swati4star/createpdf/adapter/ImageFiltersAdapter.java

@@ -27,8 +27,8 @@ public class ImageFiltersAdapter extends RecyclerView.Adapter<ImageFiltersAdapte
     private final OnFilterItemClickedListener mOnFilterItemClickedListener;
     private final Context mContext;
 
-    public ImageFiltersAdapter(ArrayList<FilterItem> filterItems, Context context,
-                               OnFilterItemClickedListener listener) {
+    public ImageFiltersAdapter(@NonNull ArrayList<FilterItem> filterItems, @NonNull Context context,
+                               @NonNull OnFilterItemClickedListener listener) {
         mFilterItem = filterItems;
         mContext = context;
         mOnFilterItemClickedListener = listener;