Releasing 1.0.0

.idea/assetWizardSettings.xml

@@ -147,7 +147,7 @@
                                 <PersistentState>
                                   <option name="values">
                                     <map>
-                                      <entry key="url" value="jar:file:/home/chronosx/%D0%94%D0%BE%D0%BA%D1%83%D0%BC%D0%B5%D0%BD%D1%82%D1%8B/bin/Android%20Studio/plugins/android/lib/android.jar!/images/material_design_icons/action/ic_favorite_black_24dp.xml" />
+                                      <entry key="url" value="jar:file:/home/chronosx/%D0%94%D0%BE%D0%BA%D1%83%D0%BC%D0%B5%D0%BD%D1%82%D1%8B/bin/Android%20Studio/plugins/android/lib/android.jar!/images/material_design_icons/content/ic_clear_black_24dp.xml" />
                                     </map>
                                   </option>
                                 </PersistentState>
@@ -157,7 +157,8 @@
                         </option>
                         <option name="values">
                           <map>
-                            <entry key="outputName" value="ic_favorite_black_24dp" />
+                            <entry key="color" value="d3d3d3" />
+                            <entry key="outputName" value="ic_clear_gray_24dp" />
                             <entry key="sourceFile" value="$USER_HOME$" />
                           </map>
                         </option>

.idea/vcs.xml

@@ -2,6 +2,5 @@
 <project version="4">
   <component name="VcsDirectoryMappings">
     <mapping directory="" vcs="Git" />
-    <mapping directory="$PROJECT_DIR$" vcs="Git" />
   </component>
 </project>

app/build.gradle

@@ -1,14 +1,18 @@
 apply plugin: 'com.android.application'
 
 android {
-    compileSdkVersion 27
+    compileSdkVersion 28
     defaultConfig {
         applicationId "ru.volgorobot.vrcatalog"
         minSdkVersion 19
         targetSdkVersion 27
         versionCode 7
         versionName "0.5.0"
-        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
+        javaCompileOptions {
+            annotationProcessorOptions {
+                arguments = ["room.schemaLocation": "$projectDir/schemas".toString()]
+            }
+        }
     }
     compileOptions {
         sourceCompatibility JavaVersion.VERSION_1_8
@@ -24,15 +28,19 @@ android {
 }
 
 dependencies {
+    def room_version = "2.1.0-alpha04"
     implementation fileTree(include: ['*.jar'], dir: 'libs')
-    implementation 'com.android.support:appcompat-v7:27.1.1'
+    implementation 'androidx.appcompat:appcompat:1.0.2'
-    implementation 'com.android.support:design:27.1.1'
+    implementation 'com.google.android.material:material:1.0.0'
-    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
+    implementation 'androidx.constraintlayout:constraintlayout:1.1.2'
     implementation 'me.texy.treeview:treeview_lib:1.0.4'
     implementation 'com.google.code.gson:gson:2.8.2'
     implementation 'com.squareup.retrofit2:retrofit:2.4.0'
     implementation 'com.squareup.retrofit2:converter-gson:2.4.0'
-    implementation 'com.android.support:recyclerview-v7:27.1.1'
+    implementation 'androidx.recyclerview:recyclerview:1.0.0-beta01'
     implementation 'com.squareup.picasso:picasso:2.71828'
     implementation 'com.github.chrisbanes:PhotoView:2.1.4'
+
+    implementation "androidx.room:room-runtime:$room_version"
+    annotationProcessor "androidx.room:room-compiler:$room_version"
 }

app/schemas/ru.volgorobot.vrcatalog.additional.AppDatabase/1.json

@@ -0,0 +1,46 @@
+{
+  "formatVersion": 1,
+  "database": {
+    "version": 1,
+    "identityHash": "b484b5731c959dea19f42d92a1fccfcd",
+    "entities": [
+      {
+        "tableName": "favorites",
+        "createSql": "CREATE TABLE IF NOT EXISTS `${TABLE_NAME}` (`id` INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, `itemID` INTEGER NOT NULL, `itemName` TEXT)",
+        "fields": [
+          {
+            "fieldPath": "id",
+            "columnName": "id",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "itemID",
+            "columnName": "itemID",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "itemName",
+            "columnName": "itemName",
+            "affinity": "TEXT",
+            "notNull": false
+          }
+        ],
+        "primaryKey": {
+          "columnNames": [
+            "id"
+          ],
+          "autoGenerate": true
+        },
+        "indices": [],
+        "foreignKeys": []
+      }
+    ],
+    "views": [],
+    "setupQueries": [
+      "CREATE TABLE IF NOT EXISTS room_master_table (id INTEGER PRIMARY KEY,identity_hash TEXT)",
+      "INSERT OR REPLACE INTO room_master_table (id,identity_hash) VALUES(42, \"b484b5731c959dea19f42d92a1fccfcd\")"
+    ]
+  }
+}

app/schemas/ru.volgorobot.vrcatalog.additional.DatabaseHelper/1.json

@@ -0,0 +1,46 @@
+{
+  "formatVersion": 1,
+  "database": {
+    "version": 1,
+    "identityHash": "b484b5731c959dea19f42d92a1fccfcd",
+    "entities": [
+      {
+        "tableName": "favorites",
+        "createSql": "CREATE TABLE IF NOT EXISTS `${TABLE_NAME}` (`id` INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, `itemID` INTEGER NOT NULL, `itemName` TEXT)",
+        "fields": [
+          {
+            "fieldPath": "id",
+            "columnName": "id",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "itemID",
+            "columnName": "itemID",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "itemName",
+            "columnName": "itemName",
+            "affinity": "TEXT",
+            "notNull": false
+          }
+        ],
+        "primaryKey": {
+          "columnNames": [
+            "id"
+          ],
+          "autoGenerate": true
+        },
+        "indices": [],
+        "foreignKeys": []
+      }
+    ],
+    "views": [],
+    "setupQueries": [
+      "CREATE TABLE IF NOT EXISTS room_master_table (id INTEGER PRIMARY KEY,identity_hash TEXT)",
+      "INSERT OR REPLACE INTO room_master_table (id,identity_hash) VALUES(42, \"b484b5731c959dea19f42d92a1fccfcd\")"
+    ]
+  }
+}

app/src/main/AndroidManifest.xml

@@ -1,5 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
-<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+<manifest
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
     package="ru.volgorobot.vrcatalog">
 
     <uses-permission android:name="android.permission.INTERNET" />
@@ -10,7 +12,8 @@
         android:label="@string/app_name"
         android:roundIcon="@mipmap/ic_launcher_round"
         android:supportsRtl="true"
-        android:theme="@style/AppTheme">
+        android:theme="@style/AppTheme"
+        android:name=".App">
         <activity android:name=".view.FavoritesActivity"></activity>
         <activity
             android:name=".view.MainActivity"

app/src/main/java/ru/volgorobot/vrcatalog/App.java

@@ -0,0 +1,25 @@
+package ru.volgorobot.vrcatalog;
+
+import android.app.Application;
+import android.content.Context;
+
+import androidx.room.Room;
+import ru.volgorobot.vrcatalog.additional.DatabaseHelper;
+
+public class App extends Application {
+    private static Application instance;
+    private static DatabaseHelper db;
+
+    @Override
+    public void onCreate() {
+        super.onCreate();
+        instance = this;
+        db = Room.databaseBuilder(getApplicationContext(), DatabaseHelper.class, "mainDatabase")
+                .allowMainThreadQueries()
+                .build();
+    }
+
+    public static Context getContext() { return instance.getApplicationContext(); }
+
+    public static DatabaseHelper getDatabaseInstance() { return db; }
+}

app/src/main/java/ru/volgorobot/vrcatalog/MainContract.java

@@ -6,8 +6,10 @@ import java.util.ArrayList;
 
 import me.texy.treeview.TreeNode;
 import ru.volgorobot.vrcatalog.additional.NetworkErrorException;
+import ru.volgorobot.vrcatalog.additional.adapters.FavoritesListAdapter;
 import ru.volgorobot.vrcatalog.model.CoreModel;
 import ru.volgorobot.vrcatalog.model.DetailModel;
+import ru.volgorobot.vrcatalog.model.FavoritesModel;
 import ru.volgorobot.vrcatalog.model.FirstLevelModel;
 import ru.volgorobot.vrcatalog.model.ImageItemModel;
 import ru.volgorobot.vrcatalog.model.SecondLevelModel;
@@ -34,12 +36,15 @@ public interface MainContract {
     }
 
     interface FavoritesPresenter {
+        void getAllItems();
+        void removeItem(int id);
         void fetchItem(int itemID);
     }
 
     interface FavoritesActivityView {
-        void onFailruleAnswer(int errorCode);
+        void onFailureAnswer(int errorCode);
         void startActivityByIntent(Intent intent);
+        void updateListView(ArrayList<FavoritesModel> data);
     }
 
     interface ViewBinder {
@@ -71,6 +76,10 @@ public interface MainContract {
 
     interface ItemPresenter {
         void getImagesByItemID(int id);
+        boolean checkFavoriteListed(int itemID);
+        int getFavoriteID(int itemID);
+        void addToFavorites(int itemID, String itemName);
+        void removeFromFavorites(int favID);
     }
 
     interface ItemView {

app/src/main/java/ru/volgorobot/vrcatalog/additional/AppCompatPreferenceActivity.java

@@ -17,11 +17,11 @@ package ru.volgorobot.vrcatalog.additional;
 import android.content.res.Configuration;
 import android.os.Bundle;
 import android.preference.PreferenceActivity;
-import android.support.annotation.LayoutRes;
+import androidx.annotation.LayoutRes;
-import android.support.annotation.Nullable;
+import androidx.annotation.Nullable;
-import android.support.v7.app.ActionBar;
+import androidx.appcompat.app.ActionBar;
-import android.support.v7.app.AppCompatDelegate;
+import androidx.appcompat.app.AppCompatDelegate;
-import android.support.v7.widget.Toolbar;
+import androidx.appcompat.widget.Toolbar;
 import android.view.MenuInflater;
 import android.view.View;
 import android.view.ViewGroup;

app/src/main/java/ru/volgorobot/vrcatalog/additional/DatabaseHelper.java

@@ -0,0 +1,11 @@
+package ru.volgorobot.vrcatalog.additional;
+
+import androidx.room.Database;
+import androidx.room.RoomDatabase;
+import ru.volgorobot.vrcatalog.model.FavoritesDaoModel;
+import ru.volgorobot.vrcatalog.model.FavoritesModel;
+
+@Database(entities = {FavoritesModel.class}, version = 1)
+public abstract class DatabaseHelper extends RoomDatabase {
+    public abstract FavoritesDaoModel getFavoritesDaoModel();
+}

app/src/main/java/ru/volgorobot/vrcatalog/additional/HackyViewPager.java

@@ -0,0 +1,42 @@
+package ru.volgorobot.vrcatalog.additional;
+
+import android.content.Context;
+import android.util.AttributeSet;
+import android.view.MotionEvent;
+
+import androidx.viewpager.widget.ViewPager;
+
+/**
+ * ViewPager fixer class (which fix bug with zooming)
+ */
+
+public class HackyViewPager extends ViewPager {
+
+    public HackyViewPager(Context context) {
+        super(context);
+    }
+
+    public HackyViewPager(Context context, AttributeSet attrs) {
+        super(context, attrs);
+    }
+
+    @Override
+    public boolean onTouchEvent(MotionEvent ev) {
+        try {
+            return super.onTouchEvent(ev);
+        } catch (IllegalArgumentException ex) {
+            ex.printStackTrace();
+        }
+        return false;
+    }
+
+    @Override
+    public boolean onInterceptTouchEvent(MotionEvent ev) {
+        try {
+            return super.onInterceptTouchEvent(ev);
+        } catch (IllegalArgumentException ex) {
+            ex.printStackTrace();
+        }
+        return false;
+    }
+}

app/src/main/java/ru/volgorobot/vrcatalog/additional/SearchableNodeViewFactory.java

@@ -23,9 +23,9 @@ public class SearchableNodeViewFactory extends BaseNodeViewFactory {
     public BaseNodeViewBinder getNodeViewBinder(View view, int level) {
         switch (level) {
             case 0:
-                return new FirstLevelNodeViewBinder(view);
+                return new FirstLevelNodeViewBinder(view, mView);
             case 1:
-                return new SecondLevelNodeViewBinder(view);
+                return new SecondLevelNodeViewBinder(view, mView);
             case 2:
                 return new ThirdLevelNodeViewBinder(view, context, mView);
             default:

app/src/main/java/ru/volgorobot/vrcatalog/additional/adapters/FavoritesListAdapter.java

@@ -3,25 +3,22 @@ package ru.volgorobot.vrcatalog.additional.adapters;
 import android.content.Context;
 import android.widget.ArrayAdapter;
 
+import java.util.ArrayList;
 import java.util.List;
 
-import ru.volgorobot.vrcatalog.model.FavoritesListModel;
+import ru.volgorobot.vrcatalog.model.FavoritesModel;
-import ru.volgorobot.vrcatalog.presenters.FavoritesDBPresenter;
 
-public class FavoritesListAdapter extends ArrayAdapter<FavoritesListModel> {
+public class FavoritesListAdapter extends ArrayAdapter<FavoritesModel> {
-    private FavoritesDBPresenter db;
+    public FavoritesListAdapter(Context context, int resource, List<FavoritesModel> objects) {
-
-    public FavoritesListAdapter(Context context, int resource, List<FavoritesListModel> objects) {
         super(context, resource, objects);
-        db = new FavoritesDBPresenter(context);
     }
 
-    public void updateData() {
+    public void updateData(ArrayList<FavoritesModel> data) {
         super.clear();
-        super.addAll(db.selectAll());
+        super.addAll(data);
     }
 
     public int getArraySize() {
-        return db.selectAll().size();
+        return super.getCount();
     }
 }

app/src/main/java/ru/volgorobot/vrcatalog/additional/adapters/FullscreenImagePagerAdapter.java

@@ -1,9 +1,9 @@
 package ru.volgorobot.vrcatalog.additional.adapters;
 
 import android.content.Context;
-import android.support.annotation.NonNull;
+import androidx.annotation.NonNull;
-import android.support.v4.view.PagerAdapter;
+import androidx.viewpager.widget.PagerAdapter;
-import android.support.v7.widget.Toolbar;
+import androidx.appcompat.widget.Toolbar;
 import android.view.View;
 import android.view.ViewGroup;
 import android.view.animation.AccelerateInterpolator;

app/src/main/java/ru/volgorobot/vrcatalog/additional/adapters/ImagePagerAdapter.java

@@ -5,8 +5,8 @@ import android.content.Intent;
 import android.graphics.Bitmap;
 import android.net.Uri;
 import android.provider.MediaStore;
-import android.support.annotation.NonNull;
+import androidx.annotation.NonNull;
-import android.support.v4.view.PagerAdapter;
+import androidx.viewpager.widget.PagerAdapter;
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.ImageView;

app/src/main/java/ru/volgorobot/vrcatalog/model/FavoritesDaoModel.java

@@ -0,0 +1,22 @@
+package ru.volgorobot.vrcatalog.model;
+
+import java.util.List;
+
+import androidx.room.Dao;
+import androidx.room.Insert;
+import androidx.room.Query;
+
+@Dao
+public interface FavoritesDaoModel {
+    @Query("SELECT * FROM favorites")
+    List<FavoritesModel> getAll();
+
+    @Query("SELECT * FROM favorites WHERE itemID = :itemID")
+    List<FavoritesModel> getFavoriteByItemID(int itemID);
+
+    @Insert
+    void add(FavoritesModel model);
+
+    @Query("DELETE FROM favorites WHERE id = :id")
+    void remove(int id);
+}

app/src/main/java/ru/volgorobot/vrcatalog/model/FavoritesModel.java

@@ -1,17 +1,21 @@
 package ru.volgorobot.vrcatalog.model;
 
-public class FavoritesListModel {
+import androidx.room.ColumnInfo;
-    private int id;
+import androidx.room.Entity;
-    private int itemID;
+import androidx.room.PrimaryKey;
-    private String itemName;
 
-    public FavoritesListModel(int itemID, String itemName) {
+@Entity(tableName = "favorites")
-        this.itemID = itemID;
+public class FavoritesModel {
-        this.itemName = itemName;
+    @PrimaryKey(autoGenerate = true)
-    }
+    public int id;
 
-    public FavoritesListModel(int id, int itemID, String itemName) {
+    @ColumnInfo
-        this.id = id;
+    public int itemID;
+
+    @ColumnInfo
+    public String itemName;
+
+    public FavoritesModel(int itemID, String itemName) {
         this.itemID = itemID;
         this.itemName = itemName;
     }

app/src/main/java/ru/volgorobot/vrcatalog/nodeViewBinders/FirstLevelNodeViewBinder.java

@@ -32,6 +32,7 @@ public class FirstLevelNodeViewBinder extends BaseNodeViewBinder implements Main
     @Override
     public void bindView(TreeNode treeNode) {
         textView.setText(treeNode.getValue().toString());
+        imageView.setRotation(treeNode.isExpanded() ? 90 : 0);
     }
 
     @Override
@@ -48,4 +49,5 @@ public class FirstLevelNodeViewBinder extends BaseNodeViewBinder implements Main
     public void rotateImageView() {
         imageView.animate().rotation(90).setDuration(200).start();
     }
+
 }

app/src/main/java/ru/volgorobot/vrcatalog/nodeViewBinders/SecondLevelNodeViewBinder.java

@@ -1,8 +1,10 @@
 package ru.volgorobot.vrcatalog.nodeViewBinders;
 
 import android.content.Context;
+import android.graphics.Color;
 import android.view.View;
 import android.widget.ImageView;
+import android.widget.RelativeLayout;
 import android.widget.TextView;
 
 import me.texy.treeview.TreeNode;

app/src/main/java/ru/volgorobot/vrcatalog/nodeViewBinders/ThirdLevelNodeViewBinder.java

@@ -1,7 +1,9 @@
 package ru.volgorobot.vrcatalog.nodeViewBinders;
 
 import android.content.Context;
+import android.graphics.Color;
 import android.view.View;
+import android.widget.RelativeLayout;
 import android.widget.TextView;
 
 import me.texy.treeview.TreeNode;

app/src/main/java/ru/volgorobot/vrcatalog/presenters/FavoritesDBPresenter.java

@@ -1,83 +0,0 @@
-package ru.volgorobot.vrcatalog.presenters;
-
-import android.content.ContentValues;
-import android.content.Context;
-import android.database.Cursor;
-import android.database.sqlite.SQLiteDatabase;
-
-import java.util.ArrayList;
-
-import ru.volgorobot.vrcatalog.additional.DatabaseProperties;
-import ru.volgorobot.vrcatalog.additional.SqliteHelper;
-import ru.volgorobot.vrcatalog.model.FavoritesListModel;
-
-public class FavoritesDBPresenter {
-    private SqliteHelper mHelper;
-    private SQLiteDatabase mDB;
-
-    public FavoritesDBPresenter(Context context) {
-        this.mHelper = new SqliteHelper(context);
-        this.mDB = mHelper.getWritableDatabase();
-    }
-
-    public ArrayList<FavoritesListModel> selectAll() {
-        ArrayList<FavoritesListModel> models = new ArrayList<>();
-
-        String[] columns = {
-                DatabaseProperties.FAVORITES_COLUMN_ID,
-                DatabaseProperties.FAVORITES_COLUMN_ITEM_ID,
-                DatabaseProperties.FAVORITES_COLUMN_ITEM_NAME
-        };
-
-        Cursor cursor = mDB.query(DatabaseProperties.FAVORITES_TABLE_NAME, columns, null, null, null, null, null);
-
-        if(cursor == null)
-            return new ArrayList<>();
-
-        while(cursor.moveToNext()) {
-            models.add(new FavoritesListModel(
-                    cursor.getInt(cursor.getColumnIndex(DatabaseProperties.FAVORITES_COLUMN_ID)),
-                    cursor.getInt(cursor.getColumnIndex(DatabaseProperties.FAVORITES_COLUMN_ITEM_ID)),
-                    cursor.getString(cursor.getColumnIndex(DatabaseProperties.FAVORITES_COLUMN_ITEM_NAME))));
-        }
-
-        cursor.close();
-
-        return models;
-    }
-
-    public void add(FavoritesListModel model) {
-        ContentValues contentValues = new ContentValues();
-        contentValues.put(DatabaseProperties.FAVORITES_COLUMN_ITEM_ID, model.getItemID());
-        contentValues.put(DatabaseProperties.FAVORITES_COLUMN_ITEM_NAME, model.getItemName());
-        mDB.insert(DatabaseProperties.FAVORITES_TABLE_NAME, null, contentValues);
-    }
-
-    public void removeItem(int id) {
-        mDB.delete(DatabaseProperties.FAVORITES_TABLE_NAME, "_id = " + id, null);
-    }
-
-    public boolean inFavoritesList(int itemID) {
-        String[] columns = { DatabaseProperties.FAVORITES_COLUMN_ITEM_ID };
-        String[] selectionArgs = { Integer.toString(itemID) };
-        Cursor cursor = mDB.query(DatabaseProperties.FAVORITES_TABLE_NAME, columns, DatabaseProperties.FAVORITES_COLUMN_ITEM_ID + " = ?", selectionArgs, null, null, null);
-        while(cursor.moveToNext()) {
-            if(cursor.getInt(cursor.getColumnIndex(DatabaseProperties.FAVORITES_COLUMN_ITEM_ID)) == itemID)
-                return true;
-        }
-        cursor.close();
-
-        return false;
-    }
-
-    public int getFavoriteID(int itemID) {
-        String[] columns = { DatabaseProperties.FAVORITES_COLUMN_ID, DatabaseProperties.FAVORITES_COLUMN_ITEM_ID };
-        Cursor cursor = mDB.query(DatabaseProperties.FAVORITES_TABLE_NAME, columns, DatabaseProperties.FAVORITES_COLUMN_ITEM_ID + " = " + Integer.toString(itemID), null, null, null, null);
-        int id = 0;
-        if( cursor != null && cursor.moveToFirst() ){
-            id = cursor.getInt(cursor.getColumnIndex(DatabaseProperties.FAVORITES_COLUMN_ID));
-            cursor.close();
-        }
-        return id;
-    }
-}

app/src/main/java/ru/volgorobot/vrcatalog/presenters/FavoritesPresenter.java

@@ -1,16 +1,21 @@
 package ru.volgorobot.vrcatalog.presenters;
 
+import android.annotation.SuppressLint;
 import android.content.Context;
 import android.content.Intent;
 import android.os.AsyncTask;
 
 import java.util.ArrayList;
 
+import androidx.room.Room;
+import ru.volgorobot.vrcatalog.App;
 import ru.volgorobot.vrcatalog.MainContract;
+import ru.volgorobot.vrcatalog.additional.DatabaseHelper;
 import ru.volgorobot.vrcatalog.additional.NetworkErrorException;
 import ru.volgorobot.vrcatalog.additional.ResultWithErrorCode;
 import ru.volgorobot.vrcatalog.model.CoreModel;
 import ru.volgorobot.vrcatalog.model.DetailModel;
+import ru.volgorobot.vrcatalog.model.FavoritesModel;
 import ru.volgorobot.vrcatalog.view.FavoritesActivity;
 import ru.volgorobot.vrcatalog.view.ItemActivity;
 
@@ -18,13 +23,16 @@ public class FavoritesPresenter implements MainContract.FavoritesPresenter {
     private Context mContext;
     private MainContract.MainModel mainModel;
     private MainContract.FavoritesActivityView mView;
+    private DatabaseHelper db;
 
-    public FavoritesPresenter(Context context, FavoritesActivity view) {
+    public FavoritesPresenter(FavoritesActivity view) {
-        this.mContext = context;
+        this.mContext = App.getContext();
-        this.mainModel = new CoreModel(context);
+        this.mainModel = new CoreModel(mContext);
         this.mView = view;
+        this.db = App.getDatabaseInstance();
     }
 
+    @SuppressLint("StaticFieldLeak")
     @Override
     public void fetchItem(int itemID) {
         new AsyncTask<Integer, Void, ResultWithErrorCode<DetailModel>>() {
@@ -59,19 +67,30 @@ public class FavoritesPresenter implements MainContract.FavoritesPresenter {
                         break;
                     }
                     case 1: {
-                        mView.onFailruleAnswer(1);
+                        mView.onFailureAnswer(1);
                         break;
                     }
                     case 2: {
-                        mView.onFailruleAnswer(2);
+                        mView.onFailureAnswer(2);
                         break;
                     }
                     case 3: {
-                        mView.onFailruleAnswer(3);
+                        mView.onFailureAnswer(3);
                         break;
                     }
                 }
             }
         }.execute(itemID);
     }
+
+    @Override
+    public void getAllItems() {
+        mView.updateListView((ArrayList<FavoritesModel>) db.getFavoritesDaoModel().getAll());
+    }
+
+    @Override
+    public void removeItem(int id) {
+        db.getFavoritesDaoModel().remove(id);
+        mView.updateListView((ArrayList<FavoritesModel>) db.getFavoritesDaoModel().getAll());
+    }
 }

app/src/main/java/ru/volgorobot/vrcatalog/presenters/ItemPresenter.java

@@ -15,21 +15,27 @@ import java.io.IOException;
 import java.util.ArrayList;
 import java.util.UUID;
 
+import androidx.room.Room;
+import ru.volgorobot.vrcatalog.App;
 import ru.volgorobot.vrcatalog.MainContract;
+import ru.volgorobot.vrcatalog.additional.DatabaseHelper;
 import ru.volgorobot.vrcatalog.additional.NetworkErrorException;
 import ru.volgorobot.vrcatalog.additional.ResultWithErrorCode;
 import ru.volgorobot.vrcatalog.model.CoreModel;
+import ru.volgorobot.vrcatalog.model.FavoritesModel;
 import ru.volgorobot.vrcatalog.model.ImageItemModel;
 
 public class ItemPresenter implements MainContract.ItemPresenter {
     private MainContract.ItemView mView;
     private Context context;
     private MainContract.MainModel coreModel;
+    private DatabaseHelper db;
 
-    public ItemPresenter(Context context, MainContract.ItemView itemView) {
+    public ItemPresenter(MainContract.ItemView itemView) {
         this.mView = itemView;
-        this.context = context;
+        this.context = App.getContext();
         this.coreModel = new CoreModel(context);
+        this.db = App.getDatabaseInstance();
     }
 
     @SuppressLint("StaticFieldLeak")
@@ -101,4 +107,27 @@ public class ItemPresenter implements MainContract.ItemPresenter {
         }
         return Uri.fromFile(cacheObject);
     }
+
+    @Override
+    public boolean checkFavoriteListed(int itemID) {
+        return db.getFavoritesDaoModel().getFavoriteByItemID(itemID).size() != 0;
+    }
+
+    @Override
+    public int getFavoriteID(int itemID) {
+        ArrayList<FavoritesModel> models = (ArrayList<FavoritesModel>) db.getFavoritesDaoModel().getFavoriteByItemID(itemID);
+        if(models.size() != 0)
+            return models.get(0).getID();
+        return 0;
+    }
+
+    @Override
+    public void addToFavorites(int itemID, String itemName) {
+        db.getFavoritesDaoModel().add(new FavoritesModel(itemID, itemName));
+    }
+
+    @Override
+    public void removeFromFavorites(int favID) {
+        db.getFavoritesDaoModel().remove(favID);
+    }
 }

app/src/main/java/ru/volgorobot/vrcatalog/presenters/ViewBinderPresenter.java

@@ -32,7 +32,7 @@ public class ViewBinderPresenter implements MainContract.LevelLoaderPresenter {
 
     @Override
     public void fetchSecondLevel(FirstLevelModel firstLevelModel, TreeNode treeNode) {
-        new AsyncTask<FirstLevelModel, Void, ResultWithErrorCode<ArrayList<SecondLevelModel>>>() {
+        new AsyncTask<FirstLevelModel, Void, ResultWithErrorCode<ArrayList<TreeNode>>>() {
             @Override
             protected void onPreExecute() {
                 super.onPreExecute();
@@ -40,31 +40,32 @@ public class ViewBinderPresenter implements MainContract.LevelLoaderPresenter {
             }
 
             @Override
-            protected ResultWithErrorCode<ArrayList<SecondLevelModel>> doInBackground(FirstLevelModel... firstLevelModel) {
+            protected ResultWithErrorCode<ArrayList<TreeNode>> doInBackground(FirstLevelModel... firstLevelModel) {
                 ArrayList<SecondLevelModel> secondLevelModels = null;
+                ArrayList<TreeNode> treeNodes = new ArrayList<>();
                 try {
                     secondLevelModels = coreModel.fetchSecondLevelByParentID(firstLevelModel[0].getID());
                 } catch (NetworkErrorException networkErrorException) {
-                    return new ResultWithErrorCode<>(secondLevelModels, networkErrorException.getErrorCode());
+                    return new ResultWithErrorCode<>(null, networkErrorException.getErrorCode());
                 } catch (NullPointerException nullPointerException) {
-                    return new ResultWithErrorCode<>(secondLevelModels, 3);
+                    return new ResultWithErrorCode<>(null, 3);
                 }
 
-                return new ResultWithErrorCode<>(secondLevelModels, 0);
+                for (int i = 0; i < secondLevelModels.size(); i++) {
+                    TreeNode treeNode = new TreeNode(secondLevelModels.get(i));
+                    treeNode.setLevel(1);
+                    treeNodes.add(treeNode);
+                }
+
+                return new ResultWithErrorCode<>(treeNodes, 0);
             }
 
             @Override
-            protected void onPostExecute(ResultWithErrorCode<ArrayList<SecondLevelModel>> result) {
+            protected void onPostExecute(ResultWithErrorCode<ArrayList<TreeNode>> result) {
                 super.onPostExecute(result);
                 switch (result.getErrorCode()) {
                     case 0: {
-                        ArrayList<TreeNode> treeNodes = new ArrayList<>();
+                        treeNode.setChildren(result.getData());
-                        for (int i = 0; i < result.getData().size(); i++) {
-                            TreeNode treeNode1 = new TreeNode(result.getData().get(i));
-                            treeNode1.setLevel(1);
-                            treeNodes.add(treeNode1);
-                        }
-                        treeNode.setChildren(treeNodes);
                         mView.refreshTree();
                         viewBinder.rotateImageView();
                         break;
@@ -89,7 +90,7 @@ public class ViewBinderPresenter implements MainContract.LevelLoaderPresenter {
 
     @Override
     public void fetchThirdLevel(SecondLevelModel secondLevelModel, TreeNode treeNode) {
-        new AsyncTask<SecondLevelModel, Void, ResultWithErrorCode<ArrayList<ThirdLevelModel>>>() {
+        new AsyncTask<SecondLevelModel, Void, ResultWithErrorCode<ArrayList<TreeNode>>>() {
             @Override
             protected void onPreExecute() {
                 super.onPreExecute();
@@ -97,30 +98,32 @@ public class ViewBinderPresenter implements MainContract.LevelLoaderPresenter {
             }
 
             @Override
-            protected ResultWithErrorCode<ArrayList<ThirdLevelModel>> doInBackground(SecondLevelModel... secondLevelModel) {
+            protected ResultWithErrorCode<ArrayList<TreeNode>> doInBackground(SecondLevelModel... secondLevelModel) {
                 ArrayList<ThirdLevelModel> thirdLevelModels = null;
+                ArrayList<TreeNode> treeNodes = new ArrayList<>();
                 try {
                     thirdLevelModels = coreModel.fetchThirdLevelByParentID(secondLevelModel[0].getID());
                 } catch (NetworkErrorException networkErrorException) {
-                    return new ResultWithErrorCode<>(thirdLevelModels, networkErrorException.getErrorCode());
+                    return new ResultWithErrorCode<>(null, networkErrorException.getErrorCode());
                 } catch (NullPointerException nullPointerException) {
-                    return new ResultWithErrorCode<>(thirdLevelModels, 3);
+                    return new ResultWithErrorCode<>(null, 3);
                 }
-                return new ResultWithErrorCode<>(thirdLevelModels, 0);
+
+                for (int i = 0; i < thirdLevelModels.size(); i++) {
+                    TreeNode treeNode1 = new TreeNode(thirdLevelModels.get(i));
+                    treeNode1.setLevel(2);
+                    treeNodes.add(treeNode1);
+                }
+
+                return new ResultWithErrorCode<>(treeNodes, 0);
             }
 
             @Override
-            protected void onPostExecute(ResultWithErrorCode<ArrayList<ThirdLevelModel>> result) {
+            protected void onPostExecute(ResultWithErrorCode<ArrayList<TreeNode>> result) {
                 super.onPostExecute(result);
                 switch (result.getErrorCode()) {
                     case 0: {
-                        ArrayList<TreeNode> treeNodes = new ArrayList<>();
+                        treeNode.setChildren(result.getData());
-                        for (int i = 0; i < result.getData().size(); i++) {
-                            TreeNode treeNode1 = new TreeNode(result.getData().get(i));
-                            treeNode1.setLevel(2);
-                            treeNodes.add(treeNode1);
-                        }
-                        treeNode.setChildren(treeNodes);
                         mView.refreshTree();
                         viewBinder.rotateImageView();
                         break;

app/src/main/java/ru/volgorobot/vrcatalog/searchNodeViewBinders/FirstLevelNodeViewBinder.java

@@ -1,18 +1,21 @@
 package ru.volgorobot.vrcatalog.searchNodeViewBinders;
 
+import android.graphics.Color;
 import android.view.View;
 import android.widget.ImageView;
+import android.widget.RelativeLayout;
 import android.widget.TextView;
 
 import me.texy.treeview.TreeNode;
 import me.texy.treeview.base.BaseNodeViewBinder;
+import ru.volgorobot.vrcatalog.MainContract;
 import ru.volgorobot.vrcatalog.R;
 
 public class FirstLevelNodeViewBinder extends BaseNodeViewBinder {
     TextView textView;
     ImageView imageView;
 
-    public FirstLevelNodeViewBinder(View itemView) {
+    public FirstLevelNodeViewBinder(View itemView, MainContract.MainActivityView mView) {
         super(itemView);
         textView = (TextView) itemView.findViewById(R.id.node_name_view);
         imageView = (ImageView) itemView.findViewById(R.id.arrow_img);
@@ -26,6 +29,7 @@ public class FirstLevelNodeViewBinder extends BaseNodeViewBinder {
     @Override
     public void bindView(TreeNode treeNode) {
         textView.setText(treeNode.getValue().toString());
+        imageView.setRotation(treeNode.isExpanded() ? 90 : 0);
     }
 
     @Override

app/src/main/java/ru/volgorobot/vrcatalog/searchNodeViewBinders/SecondLevelNodeViewBinder.java

@@ -1,18 +1,21 @@
 package ru.volgorobot.vrcatalog.searchNodeViewBinders;
 
+import android.graphics.Color;
 import android.view.View;
 import android.widget.ImageView;
+import android.widget.RelativeLayout;
 import android.widget.TextView;
 
 import me.texy.treeview.TreeNode;
 import me.texy.treeview.base.BaseNodeViewBinder;
+import ru.volgorobot.vrcatalog.MainContract;
 import ru.volgorobot.vrcatalog.R;
 
 public class SecondLevelNodeViewBinder extends BaseNodeViewBinder {
     TextView textView;
     ImageView imageView;
 
-    public SecondLevelNodeViewBinder(View itemView) {
+    public SecondLevelNodeViewBinder(View itemView, MainContract.MainActivityView mView) {
         super(itemView);
         textView = (TextView) itemView.findViewById(R.id.node_name_view);
         imageView = (ImageView) itemView.findViewById(R.id.arrow_img);
@@ -26,6 +29,7 @@ public class SecondLevelNodeViewBinder extends BaseNodeViewBinder {
     @Override
     public void bindView(TreeNode treeNode) {
         textView.setText(treeNode.getValue().toString());
+        imageView.setRotation(treeNode.isExpanded() ? 90 : 0);
     }
 
     @Override

app/src/main/java/ru/volgorobot/vrcatalog/view/AboutActivity.java

@@ -1,7 +1,7 @@
 package ru.volgorobot.vrcatalog.view;
 
 import android.os.Bundle;
-import android.support.v7.app.AppCompatActivity;
+import androidx.appcompat.app.AppCompatActivity;
 import android.view.MenuItem;
 
 import ru.volgorobot.vrcatalog.R;

app/src/main/java/ru/volgorobot/vrcatalog/view/FavoritesActivity.java

@@ -1,8 +1,8 @@
 package ru.volgorobot.vrcatalog.view;
 
 import android.content.Intent;
-import android.support.v7.app.ActionBar;
+import androidx.appcompat.app.ActionBar;
-import android.support.v7.app.AppCompatActivity;
+import androidx.appcompat.app.AppCompatActivity;
 import android.os.Bundle;
 import android.util.Log;
 import android.view.ContextMenu;
@@ -19,12 +19,10 @@ import java.util.ArrayList;
 import ru.volgorobot.vrcatalog.MainContract;
 import ru.volgorobot.vrcatalog.R;
 import ru.volgorobot.vrcatalog.additional.adapters.FavoritesListAdapter;
-import ru.volgorobot.vrcatalog.model.FavoritesListModel;
+import ru.volgorobot.vrcatalog.model.FavoritesModel;
-import ru.volgorobot.vrcatalog.presenters.FavoritesDBPresenter;
 import ru.volgorobot.vrcatalog.presenters.FavoritesPresenter;
 
 public class FavoritesActivity extends AppCompatActivity implements MainContract.FavoritesActivityView {
-    private FavoritesDBPresenter db;
     private FavoritesListAdapter adapter;
     private MainContract.FavoritesPresenter mPresenter;
 
@@ -37,15 +35,13 @@ public class FavoritesActivity extends AppCompatActivity implements MainContract
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_favorites);
 
-        mPresenter = new FavoritesPresenter(FavoritesActivity.this, this);
+        mPresenter = new FavoritesPresenter(this);
 
         ActionBar actionBar = getSupportActionBar();
         actionBar.setDisplayHomeAsUpEnabled(true);
         actionBar.setHomeButtonEnabled(true);
         actionBar.setTitle("Избранное");
 
-        db = new FavoritesDBPresenter(FavoritesActivity.this);
-
         initViews();
     }
 
@@ -55,16 +51,14 @@ public class FavoritesActivity extends AppCompatActivity implements MainContract
         listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
             @Override
             public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
-                FavoritesListModel model = (FavoritesListModel) listView.getItemAtPosition(i);
+                FavoritesModel model = (FavoritesModel) listView.getItemAtPosition(i);
                 mPresenter.fetchItem(model.getItemID());
             }
         });
+        adapter = new FavoritesListAdapter(FavoritesActivity.this, android.R.layout.simple_list_item_1, new ArrayList<>());
+        listView.setAdapter(adapter);
         favoritesEmptyImage = findViewById(R.id.favorites_empty_image);
         favoritesEmptyText = findViewById(R.id.favorites_empty_text);
-        ArrayList<FavoritesListModel> models = db.selectAll();
-        adapter = new FavoritesListAdapter(FavoritesActivity.this, android.R.layout.simple_list_item_1, models);
-        listView.setAdapter(adapter);
-        checkForEmptyContent();
     }
 
     public void checkForEmptyContent() {
@@ -84,17 +78,18 @@ public class FavoritesActivity extends AppCompatActivity implements MainContract
         AdapterView.AdapterContextMenuInfo info = (AdapterView.AdapterContextMenuInfo) item.getMenuInfo();
         switch (item.getItemId()) {
             case 0: {
-                FavoritesListModel model = (FavoritesListModel) listView.getItemAtPosition(info.position);
+                FavoritesModel model = (FavoritesModel) listView.getItemAtPosition(info.position);
-                db.removeItem(model.getID());
+                mPresenter.removeItem(model.getID());
-                updateListView();
             }
         }
         return true;
     }
 
-    private void updateListView() {
+    @Override
-        adapter.updateData();
+    public void updateListView(ArrayList<FavoritesModel> data) {
+        adapter.updateData(data);
         adapter.notifyDataSetChanged();
+        checkForEmptyContent();
     }
 
     @Override
@@ -115,7 +110,7 @@ public class FavoritesActivity extends AppCompatActivity implements MainContract
     }
 
     @Override
-    public void onFailruleAnswer(int errorCode) {
+    public void onFailureAnswer(int errorCode) {
         switch (errorCode) {
             case 1: {
                 Toast.makeText(FavoritesActivity.this, "Ошибка сети. Проверьте подключение к сети или данные подключения к API!", Toast.LENGTH_LONG).show();
@@ -143,7 +138,6 @@ public class FavoritesActivity extends AppCompatActivity implements MainContract
     @Override
     protected void onResume() {
         super.onResume();
-        updateListView();
+        mPresenter.getAllItems();
-        checkForEmptyContent();
     }
 }

app/src/main/java/ru/volgorobot/vrcatalog/view/FullScreenImageActivity.java

@@ -4,11 +4,11 @@ import android.graphics.Color;
 import android.graphics.PorterDuff;
 import android.graphics.drawable.Drawable;
 import android.os.Bundle;
-import android.support.annotation.Nullable;
+import androidx.annotation.Nullable;
-import android.support.v4.content.ContextCompat;
+import androidx.core.content.ContextCompat;
-import android.support.v4.view.ViewPager;
+import androidx.viewpager.widget.ViewPager;
-import android.support.v7.app.AppCompatActivity;
+import androidx.appcompat.app.AppCompatActivity;
-import android.support.v7.widget.Toolbar;
+import androidx.appcompat.widget.Toolbar;
 import android.view.MenuItem;
 import android.view.View;
 import android.view.Window;

app/src/main/java/ru/volgorobot/vrcatalog/view/ItemActivity.java

@@ -4,10 +4,11 @@ import android.content.Intent;
 import android.graphics.Bitmap;
 import android.graphics.Color;
 import android.os.Bundle;
-import android.support.design.widget.TabLayout;
+import com.google.android.material.tabs.TabLayout;
-import android.support.v4.view.ViewPager;
+
-import android.support.v7.app.AppCompatActivity;
+import androidx.viewpager.widget.ViewPager;
-import android.support.v7.widget.Toolbar;
+import androidx.appcompat.app.AppCompatActivity;
+import androidx.appcompat.widget.Toolbar;
 import android.util.Log;
 import android.view.Menu;
 import android.view.MenuInflater;
@@ -17,10 +18,7 @@ import android.widget.TextView;
 import android.widget.Toast;
 
 import java.util.LinkedHashMap;
-import java.util.Map;
 
-import ru.volgorobot.vrcatalog.model.FavoritesListModel;
-import ru.volgorobot.vrcatalog.presenters.FavoritesDBPresenter;
 import ru.volgorobot.vrcatalog.presenters.ItemPresenter;
 import ru.volgorobot.vrcatalog.MainContract;
 import ru.volgorobot.vrcatalog.R;
@@ -33,9 +31,9 @@ public class ItemActivity extends AppCompatActivity implements MainContract.Item
     private ListView propertiesList;
     private ImagePagerAdapter imagePagerAdapter;
     private boolean inFavorites;
-    private FavoritesDBPresenter db;
     private int itemID;
     private String itemName;
+    private int favoriteID;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
@@ -47,7 +45,7 @@ public class ItemActivity extends AppCompatActivity implements MainContract.Item
         getSupportActionBar().setHomeButtonEnabled(true);
         getSupportActionBar().setDisplayShowTitleEnabled(false);
         initializeViews();
-        mPresenter = new ItemPresenter(ItemActivity.this, this);
+        mPresenter = new ItemPresenter(this);
         Intent intent = getIntent();
 
         itemName = intent.getStringExtra("detailName");
@@ -63,7 +61,6 @@ public class ItemActivity extends AppCompatActivity implements MainContract.Item
         LinkedHashMap<String, String> intentDataForListView = getIntentExtras(intent);
         itemID = Integer.parseInt(intent.getStringExtra("itemID"));
         intentDataForListView.get("detailName");
-        db = new FavoritesDBPresenter(ItemActivity.this);
 
         propertiesList = findViewById(R.id.propertiesList);
         PropertiesListAdapter propertiesListAdapter = new PropertiesListAdapter(intentDataForListView);
@@ -71,7 +68,8 @@ public class ItemActivity extends AppCompatActivity implements MainContract.Item
 
         mPresenter.getImagesByItemID(Integer.parseInt(intent.getStringExtra("itemID")));
 
-        inFavorites = db.inFavoritesList(itemID);
+        inFavorites = mPresenter.checkFavoriteListed(itemID);
+        favoriteID = mPresenter.getFavoriteID(itemID);
     }
 
     void initializeViews() {
@@ -229,13 +227,13 @@ public class ItemActivity extends AppCompatActivity implements MainContract.Item
         MenuItem deleteFromFavorites = menu.findItem(R.id.action_unfavorite);
 
         addToFavorites.setOnMenuItemClickListener((MenuItem menuItem) -> {
-            db.add(new FavoritesListModel(0, itemID, itemName));
+            mPresenter.addToFavorites(itemID, itemName);
             inFavorites = true;
             this.invalidateOptionsMenu();
             return true;
         });
         deleteFromFavorites.setOnMenuItemClickListener((MenuItem menuItem) -> {
-            db.removeItem(db.getFavoriteID(itemID));
+            mPresenter.removeFromFavorites(favoriteID);
             inFavorites = false;
             this.invalidateOptionsMenu();
             return true;

app/src/main/java/ru/volgorobot/vrcatalog/view/MainActivity.java

@@ -5,16 +5,15 @@ import android.content.ComponentName;
 import android.content.Context;
 import android.content.Intent;
 import android.os.Bundle;
-import android.support.design.widget.NavigationView;
+import androidx.drawerlayout.widget.DrawerLayout;
-import android.support.v4.view.GravityCompat;
+import androidx.core.view.GravityCompat;
-import android.support.v4.view.MenuItemCompat;
+import androidx.core.view.MenuItemCompat;
-import android.support.v4.widget.DrawerLayout;
+import androidx.swiperefreshlayout.widget.SwipeRefreshLayout;
-import android.support.v4.widget.SwipeRefreshLayout;
+import androidx.appcompat.app.ActionBarDrawerToggle;
-import android.support.v7.app.ActionBarDrawerToggle;
+import androidx.appcompat.app.AppCompatActivity;
-import android.support.v7.app.AppCompatActivity;
+import androidx.recyclerview.widget.DefaultItemAnimator;
-import android.support.v7.widget.DefaultItemAnimator;
+import androidx.appcompat.widget.SearchView;
-import android.support.v7.widget.SearchView;
+import androidx.appcompat.widget.Toolbar;
-import android.support.v7.widget.Toolbar;
 import android.util.Log;
 import android.view.Menu;
 import android.view.MenuInflater;
@@ -25,6 +24,8 @@ import android.widget.ImageView;
 import android.widget.TextView;
 import android.widget.Toast;
 
+import com.google.android.material.navigation.NavigationView;
+
 import java.util.ArrayList;
 
 import me.texy.treeview.TreeNode;
@@ -205,7 +206,6 @@ public class MainActivity extends AppCompatActivity
         search.setQueryHint("Имя детали");
         return true;
     }
-
 }
 
 

app/src/main/java/ru/volgorobot/vrcatalog/view/SearchableActivity.java

@@ -4,14 +4,13 @@ import android.app.SearchManager;
 import android.content.Intent;
 import android.os.Bundle;
 import android.provider.SearchRecentSuggestions;
-import android.support.v4.widget.NestedScrollView;
+import androidx.core.widget.NestedScrollView;
-import android.support.v4.widget.SwipeRefreshLayout;
+import androidx.swiperefreshlayout.widget.SwipeRefreshLayout;
-import android.support.v7.app.AppCompatActivity;
+import androidx.appcompat.app.AppCompatActivity;
-import android.support.v7.widget.DefaultItemAnimator;
+import androidx.recyclerview.widget.DefaultItemAnimator;
 import android.util.Log;
 import android.view.MenuItem;
 import android.view.View;
-import android.view.ViewGroup;
 import android.widget.ImageView;
 import android.widget.TextView;
 
@@ -35,6 +34,9 @@ public class SearchableActivity extends AppCompatActivity implements MainContrac
     private ImageView mConnectionErrorImageView;
     private NestedScrollView mTreeViewContainer;
     private TextView mErrorTextView;
+    private ImageView mEmptySearchImageView;
+    private TextView mEmptySearchTextView;
+    private boolean isInErrorState = false;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
@@ -53,9 +55,12 @@ public class SearchableActivity extends AppCompatActivity implements MainContrac
         mTreeViewContainer = findViewById(R.id.searchableTreeViewContainer);
         mErrorTextView = findViewById(R.id.searchableErrorTextView);
 
+        mEmptySearchImageView = findViewById(R.id.emptySearchImage);
+        mEmptySearchTextView = findViewById(R.id.emptySearchText);
+
         treeView = new TreeView(rootNode, SearchableActivity.this, new SearchableNodeViewFactory(SearchableActivity.this, this));
         treeView.setItemAnimator(new DefaultItemAnimator());
-        ((ViewGroup) findViewById(R.id.searchableTreeViewContainer)).addView(treeView.getView());
+        mTreeViewContainer.addView(treeView.getView());
         Intent intent = getIntent();
         if (Intent.ACTION_SEARCH.equals(intent.getAction())) {
             detailName = intent.getStringExtra(SearchManager.QUERY);
@@ -72,6 +77,15 @@ public class SearchableActivity extends AppCompatActivity implements MainContrac
         rootNode.setChildren(children);
         treeView.expandAll();
         treeView.refreshTreeView();
+        if(children.size() == 0 && !isInErrorState) {
+            mEmptySearchImageView.setVisibility(View.VISIBLE);
+            mEmptySearchTextView.setVisibility(View.VISIBLE);
+            mTreeViewContainer.setVisibility(View.GONE);
+        } else {
+            mEmptySearchImageView.setVisibility(View.INVISIBLE);
+            mEmptySearchTextView.setVisibility(View.INVISIBLE);
+            mTreeViewContainer.setVisibility(View.VISIBLE);
+        }
     }
 
     public void onFailureAnswer(int errorCode) {
@@ -84,6 +98,7 @@ public class SearchableActivity extends AppCompatActivity implements MainContrac
                 mTreeViewContainer.setVisibility(View.GONE);
                 mConnectionErrorImageView.setVisibility(View.VISIBLE);
                 mErrorTextView.setVisibility(View.VISIBLE);
+                isInErrorState = true;
                 break;
             }
             case 2: {
@@ -94,6 +109,7 @@ public class SearchableActivity extends AppCompatActivity implements MainContrac
                 mTreeViewContainer.setVisibility(View.GONE);
                 mConnectionErrorImageView.setVisibility(View.VISIBLE);
                 mErrorTextView.setVisibility(View.VISIBLE);
+                isInErrorState = true;
                 break;
             }
             case 3: {
@@ -103,6 +119,7 @@ public class SearchableActivity extends AppCompatActivity implements MainContrac
                 mTreeViewContainer.setVisibility(View.GONE);
                 mConnectionErrorImageView.setVisibility(View.VISIBLE);
                 mErrorTextView.setVisibility(View.VISIBLE);
+                isInErrorState = true;
                 break;
             }
         }
@@ -116,6 +133,7 @@ public class SearchableActivity extends AppCompatActivity implements MainContrac
         rootNode.setChildren(new ArrayList<TreeNode>());
         treeView.refreshTreeView();
         searchablePresenter.fetchDetailsTreeByName(detailName);
+        isInErrorState = false;
     }
 
     @Override

app/src/main/res/drawable/ic_clear_gray_24dp.xml

@@ -0,0 +1,5 @@
+<vector android:height="24dp" android:tint="#D3D3D3"
+    android:viewportHeight="24.0" android:viewportWidth="24.0"
+    android:width="24dp" xmlns:android="http://schemas.android.com/apk/res/android">
+    <path android:fillColor="#FF000000" android:pathData="M19,6.41L17.59,5 12,10.59 6.41,5 5,6.41 10.59,12 5,17.59 6.41,19 12,13.41 17.59,19 19,17.59 13.41,12z"/>
+</vector>

app/src/main/res/layout/activity_detail.xml

@@ -1,25 +1,25 @@
 <?xml version="1.0" encoding="utf-8"?>
-<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<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="wrap_content">
 
-    <android.support.design.widget.AppBarLayout
+    <com.google.android.material.appbar.AppBarLayout
         android:layout_width="match_parent"
         android:layout_height="match_parent"
         android:fitsSystemWindows="true">
-        <android.support.design.widget.CollapsingToolbarLayout
+        <com.google.android.material.appbar.CollapsingToolbarLayout
             android:layout_width="match_parent"
             android:layout_height="match_parent"
             app:layout_scrollFlags="scroll|enterAlways">
 
-            <android.support.v4.view.ViewPager
+            <androidx.viewpager.widget.ViewPager
                 android:id="@+id/viewPager"
                 android:layout_width="wrap_content"
                 android:layout_height="311dp"
                 app:layout_collapseMode="parallax" />
-            <android.support.design.widget.TabLayout
+            <com.google.android.material.tabs.TabLayout
                 android:id="@+id/tabDots"
                 android:layout_width="match_parent"
                 android:layout_height="62dp"
@@ -27,7 +27,7 @@
                 app:tabBackground="@drawable/tab_selector"
                 app:tabGravity="center"
                 app:tabIndicatorHeight="0dp" />
-            <android.support.v7.widget.Toolbar
+            <androidx.appcompat.widget.Toolbar
                 android:id="@+id/itemactivity_toolbar"
                 android:layout_width="match_parent"
                 android:layout_height="?attr/actionBarSize"
@@ -35,10 +35,10 @@
                 app:popupTheme="@style/ThemeOverlay.AppCompat.Light"
                 android:theme="@style/ItemActionBar"/>
 
-        </android.support.design.widget.CollapsingToolbarLayout>
+        </com.google.android.material.appbar.CollapsingToolbarLayout>
-    </android.support.design.widget.AppBarLayout>
+    </com.google.android.material.appbar.AppBarLayout>
 
-    <android.support.v4.widget.NestedScrollView
+    <androidx.core.widget.NestedScrollView
         android:layout_width="match_parent"
         android:layout_height="619dp"
         app:layout_behavior="@string/appbar_scrolling_view_behavior"
@@ -74,5 +74,5 @@
                 app:layout_behavior="@string/appbar_scrolling_view_behavior"
                 android:nestedScrollingEnabled="false"/>
         </LinearLayout>
-    </android.support.v4.widget.NestedScrollView>
+    </androidx.core.widget.NestedScrollView>
-</android.support.design.widget.CoordinatorLayout>
+</androidx.coordinatorlayout.widget.CoordinatorLayout>

app/src/main/res/layout/activity_favorites.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<androidx.constraintlayout.widget.ConstraintLayout 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:id="@+id/linearLayout"
@@ -44,4 +44,4 @@
         app:layout_constraintStart_toStartOf="parent"
         app:layout_constraintTop_toBottomOf="@+id/favorites_empty_image" />
 
-</android.support.constraint.ConstraintLayout>
+</androidx.constraintlayout.widget.ConstraintLayout>

app/src/main/res/layout/activity_fullscreenimage.xml

@@ -9,12 +9,12 @@
     tools:context="ru.volgorobot.vrcatalog.view.FullScreenImageActivity"
     android:background="@android:color/black">
 
-    <android.support.v4.view.ViewPager
+    <ru.volgorobot.vrcatalog.additional.HackyViewPager
         android:id="@+id/fullscreen_mode_viewpager"
         android:layout_width="match_parent"
         android:layout_height="match_parent" />
 
-    <android.support.v7.widget.Toolbar
+    <androidx.appcompat.widget.Toolbar
         android:id="@+id/toolbar"
         android:layout_width="match_parent"
         android:layout_height="?attr/actionBarSize"

app/src/main/res/layout/activity_main.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<androidx.drawerlayout.widget.DrawerLayout 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:id="@+id/drawer_layout"
@@ -13,7 +13,7 @@
         android:layout_width="match_parent"
         android:layout_height="match_parent" />
 
-    <android.support.design.widget.NavigationView
+    <com.google.android.material.navigation.NavigationView
         android:id="@+id/nav_view"
         android:layout_width="wrap_content"
         android:layout_height="match_parent"
@@ -22,4 +22,4 @@
         app:headerLayout="@layout/nav_header_main"
         app:menu="@menu/activity_main_drawer" />
 
-</android.support.v4.widget.DrawerLayout>
+</androidx.drawerlayout.widget.DrawerLayout>

app/src/main/res/layout/activity_searchable.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<android.support.v4.widget.SwipeRefreshLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<androidx.swiperefreshlayout.widget.SwipeRefreshLayout 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"
@@ -10,16 +10,16 @@
     android:orientation="horizontal"
     android:id="@+id/searchableSwipeRefreshLayout">
 
-    <android.support.constraint.ConstraintLayout
+    <androidx.constraintlayout.widget.ConstraintLayout
         android:layout_width="match_parent"
         android:layout_height="match_parent">
 
-        <android.support.v4.widget.NestedScrollView
+        <androidx.core.widget.NestedScrollView
             android:id="@+id/searchableTreeViewContainer"
             android:layout_width="match_parent"
             android:layout_height="match_parent"
             android:scrollbarAlwaysDrawVerticalTrack="true">
-        </android.support.v4.widget.NestedScrollView>
+        </androidx.core.widget.NestedScrollView>
 
         <ImageView
             android:id="@+id/searchableConnectionErrorImageView"
@@ -44,11 +44,42 @@
             android:text=""
             android:textAppearance="@style/TextAppearance.AppCompat.Medium"
             android:visibility="invisible"
+            android:gravity="center"
             app:layout_constraintBottom_toBottomOf="parent"
             app:layout_constraintEnd_toEndOf="parent"
             app:layout_constraintStart_toStartOf="parent"
             app:layout_constraintTop_toBottomOf="@+id/searchableConnectionErrorImageView" />
 
-    </android.support.constraint.ConstraintLayout>
+        <ImageView
+            android:id="@+id/emptySearchImage"
+            android:layout_width="0dp"
+            android:layout_height="0dp"
+            android:layout_marginTop="70dp"
+            android:layout_marginBottom="52dp"
+            android:src="@drawable/ic_clear_gray_24dp"
+            android:visibility="invisible"
+            app:layout_constraintBottom_toTopOf="@+id/emptySearchText"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toTopOf="parent" />
 
-</android.support.v4.widget.SwipeRefreshLayout>
+        <TextView
+            android:id="@+id/emptySearchText"
+            android:layout_width="0dp"
+            android:layout_height="77dp"
+            android:layout_marginStart="9dp"
+            android:layout_marginEnd="9dp"
+            android:layout_marginBottom="68dp"
+            android:text="@string/empty_search"
+            android:textAppearance="@style/TextAppearance.AppCompat.Medium"
+            android:visibility="invisible"
+            android:textSize="18sp"
+            android:gravity="center"
+            app:layout_constraintBottom_toBottomOf="parent"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@+id/emptySearchImage" />
+
+    </androidx.constraintlayout.widget.ConstraintLayout>
+
+</androidx.swiperefreshlayout.widget.SwipeRefreshLayout>

app/src/main/res/layout/app_bar_main.xml

@@ -1,27 +1,27 @@
 <?xml version="1.0" encoding="utf-8"?>
-<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<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=".view.MainActivity">
 
-    <android.support.design.widget.AppBarLayout
+    <com.google.android.material.appbar.AppBarLayout
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:theme="@style/AppTheme.AppBarOverlay">
 
-        <android.support.v7.widget.Toolbar
+        <androidx.appcompat.widget.Toolbar
             android:id="@+id/toolbar"
             android:layout_width="match_parent"
             android:layout_height="?attr/actionBarSize"
             android:background="?attr/colorPrimary"
-            android:theme="@style/CustomSearchStyle"
+            android:theme="@style/MainActivity"
             app:titleTextColor="@android:color/white"
             app:popupTheme="@style/AppTheme.PopupOverlay" />
 
-    </android.support.design.widget.AppBarLayout>
+    </com.google.android.material.appbar.AppBarLayout>
 
     <include layout="@layout/content_main" />
 
-</android.support.design.widget.CoordinatorLayout>
+</androidx.coordinatorlayout.widget.CoordinatorLayout>

app/src/main/res/layout/content_main.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<android.support.v4.widget.SwipeRefreshLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<androidx.swiperefreshlayout.widget.SwipeRefreshLayout 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"
@@ -10,12 +10,12 @@
     android:orientation="horizontal"
     android:id="@+id/swipeRefreshLayout">
 
-    <android.support.constraint.ConstraintLayout
+    <androidx.constraintlayout.widget.ConstraintLayout
         android:id="@+id/mainActivityConstraint"
         android:layout_width="match_parent"
         android:layout_height="match_parent">
 
-        <android.support.v4.widget.NestedScrollView
+        <androidx.core.widget.NestedScrollView
             android:id="@+id/treeViewContainer"
             android:layout_width="0dp"
             android:layout_height="0dp"
@@ -27,7 +27,7 @@
             app:layout_constraintTop_toTopOf="parent"
             app:layout_constraintVertical_bias="1.0">
 
-        </android.support.v4.widget.NestedScrollView>
+        </androidx.core.widget.NestedScrollView>
 
         <ImageView
             android:id="@+id/connectionErrorImageView"
@@ -59,6 +59,6 @@
             app:layout_constraintStart_toStartOf="parent"
             app:layout_constraintTop_toBottomOf="@+id/connectionErrorImageView" />
 
-    </android.support.constraint.ConstraintLayout>
+    </androidx.constraintlayout.widget.ConstraintLayout>
 
-</android.support.v4.widget.SwipeRefreshLayout>
+</androidx.swiperefreshlayout.widget.SwipeRefreshLayout>

app/src/main/res/layout/first_level_item.xml

@@ -1,9 +1,14 @@
 <?xml version="1.0" encoding="utf-8"?>
 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:id="@+id/parent_node_container_1"
     android:layout_width="match_parent"
-    android:layout_height="80dp"
+    android:layout_height="50dp"
     android:background="?android:selectableItemBackground">
 
+    <View android:background="#D3D3D3"
+        android:layout_width = "match_parent"
+        android:layout_height="1dp"/>
+
     <LinearLayout
         android:id="@+id/node_container"
         android:layout_width="wrap_content"

app/src/main/res/layout/second_level_item.xml

@@ -1,10 +1,15 @@
 <?xml version="1.0" encoding="utf-8"?>
 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:id="@+id/parent_node_container_2"
     android:layout_width="match_parent"
-    android:layout_height="60dp"
+    android:layout_height="50dp"
     android:orientation="vertical"
     android:background="?android:selectableItemBackground">
 
+    <View android:background="#D3D3D3"
+        android:layout_width = "match_parent"
+        android:layout_height="1dp"/>
+
     <LinearLayout
         android:id="@+id/node_container"
         android:layout_width="wrap_content"

app/src/main/res/layout/third_level_item.xml

@@ -1,10 +1,15 @@
 <?xml version="1.0" encoding="utf-8"?>
 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:id="@+id/parent_node_container_3"
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
     android:orientation="vertical"
     android:background="?android:selectableItemBackground">
 
+    <View android:background="#D3D3D3"
+        android:layout_width = "match_parent"
+        android:layout_height="1dp"/>
+
     <LinearLayout
         android:id="@+id/node_container"
         android:layout_width="wrap_content"

app/src/main/res/menu/main.xml

@@ -5,6 +5,6 @@
         android:id="@+id/action_search"
         android:icon="@drawable/ic_search_white_24dp"
         app:showAsAction="always|collapseActionView"
-        app:actionViewClass="android.support.v7.widget.SearchView"
+        app:actionViewClass="androidx.appcompat.widget.SearchView"
         android:title="Поиск"/>
 </menu>

app/src/main/res/values-v21/styles.xml

@@ -25,7 +25,9 @@
         <item name="android:textColorPrimary">@android:color/black</item>
         <item name="android:textColorSecondary">@android:color/black</item>
     </style>
-    <style name="CustomSearchStyle" parent="AppTheme">
+    <style name="MainActivity" parent="AppTheme.NoActionBar">
+        <item name="android:editTextColor">@android:color/white</item>
+        <item name="android:textColorHint">@android:color/white</item>
         <item name="suggestionRowLayout">@layout/light_suggestion_hint</item>
         <item name="colorControlNormal">@android:color/white</item>
         <item name="android:colorControlNormal">@android:color/white</item>

app/src/main/res/values/strings.xml

@@ -3,4 +3,5 @@
     <string name="navigation_drawer_open">Open navigation drawer</string>
     <string name="navigation_drawer_close">Close navigation drawer</string>
     <string name="favorites_empty">Ваш список избранного пуст</string>
+    <string name="empty_search">По вашему запросу ничего не найдено.</string>
 </resources>

app/src/main/res/values/styles.xml

@@ -8,9 +8,6 @@
     <style name="MainActivity" parent="AppTheme.NoActionBar">
         <item name="android:editTextColor">@android:color/white</item>
         <item name="android:textColorHint">@android:color/white</item>
-    </style>
-
-    <style name="CustomSearchStyle" parent="AppTheme">
         <item name="suggestionRowLayout">@layout/light_suggestion_hint</item>
         <item name="colorControlNormal">@android:color/white</item>
     </style>

gradle.properties

@@ -6,6 +6,8 @@
 # http://www.gradle.org/docs/current/userguide/build_environment.html
 # Specifies the JVM arguments used for the daemon process.
 # The setting is particularly useful for tweaking memory settings.
+android.enableJetifier=true
+android.useAndroidX=true
 org.gradle.jvmargs=-Xmx512m
 # When configured, Gradle will run in incubating parallel mode.
 # This option should only be used with decoupled projects. More details, visit