diff --git a/.idea/codeStyles/Project.xml b/.idea/codeStyles/Project.xml
index 34dc27c..a9ea262 100644
--- a/.idea/codeStyles/Project.xml
+++ b/.idea/codeStyles/Project.xml
@@ -3,6 +3,9 @@
     <JetCodeStyleSettings>
       <option name="CODE_STYLE_DEFAULTS" value="KOTLIN_OFFICIAL" />
     </JetCodeStyleSettings>
+    <MarkdownNavigatorCodeStyleSettings>
+      <option name="RIGHT_MARGIN" value="72" />
+    </MarkdownNavigatorCodeStyleSettings>
     <Objective-C-extensions>
       <file>
         <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Import" />
diff --git a/.idea/markdown-navigator.xml b/.idea/markdown-navigator.xml
new file mode 100644
index 0000000..d030f38
--- /dev/null
+++ b/.idea/markdown-navigator.xml
@@ -0,0 +1,85 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="MarkdownProjectSettings" wasCopied="false">
+    <PreviewSettings splitEditorLayout="SPLIT" splitEditorPreview="PREVIEW" useGrayscaleRendering="false" zoomFactor="1.0" maxImageWidth="0" showGitHubPageIfSynced="false" allowBrowsingInPreview="false" synchronizePreviewPosition="true" highlightPreviewType="NONE" highlightFadeOut="5" highlightOnTyping="true" synchronizeSourcePosition="true" verticallyAlignSourceAndPreviewSyncPosition="true" showSearchHighlightsInPreview="false" showSelectionInPreview="true" openRemoteLinks="true" replaceUnicodeEmoji="false" lastLayoutSetsDefault="false">
+      <PanelProvider>
+        <provider providerId="com.vladsch.idea.multimarkdown.editor.swing.html.panel" providerName="Default - Swing" />
+      </PanelProvider>
+    </PreviewSettings>
+    <ParserSettings gitHubSyntaxChange="false" emojiShortcuts="1" emojiImages="0">
+      <PegdownExtensions>
+        <option name="ABBREVIATIONS" value="false" />
+        <option name="ANCHORLINKS" value="true" />
+        <option name="ASIDE" value="false" />
+        <option name="ATXHEADERSPACE" value="true" />
+        <option name="AUTOLINKS" value="true" />
+        <option name="DEFINITIONS" value="false" />
+        <option name="DEFINITION_BREAK_DOUBLE_BLANK_LINE" value="false" />
+        <option name="FENCED_CODE_BLOCKS" value="true" />
+        <option name="FOOTNOTES" value="false" />
+        <option name="HARDWRAPS" value="false" />
+        <option name="HTML_DEEP_PARSER" value="false" />
+        <option name="INSERTED" value="false" />
+        <option name="QUOTES" value="false" />
+        <option name="RELAXEDHRULES" value="true" />
+        <option name="SMARTS" value="false" />
+        <option name="STRIKETHROUGH" value="true" />
+        <option name="SUBSCRIPT" value="false" />
+        <option name="SUPERSCRIPT" value="false" />
+        <option name="SUPPRESS_HTML_BLOCKS" value="false" />
+        <option name="SUPPRESS_INLINE_HTML" value="false" />
+        <option name="TABLES" value="true" />
+        <option name="TASKLISTITEMS" value="true" />
+        <option name="TOC" value="false" />
+        <option name="WIKILINKS" value="false" />
+      </PegdownExtensions>
+      <ParserOptions>
+        <option name="ADMONITION_EXT" value="false" />
+        <option name="ATTRIBUTES_EXT" value="false" />
+        <option name="COMMONMARK_LISTS" value="true" />
+        <option name="DUMMY" value="false" />
+        <option name="EMOJI_SHORTCUTS" value="true" />
+        <option name="ENUMERATED_REFERENCES_EXT" value="false" />
+        <option name="FLEXMARK_FRONT_MATTER" value="false" />
+        <option name="GFM_LOOSE_BLANK_LINE_AFTER_ITEM_PARA" value="false" />
+        <option name="GFM_TABLE_RENDERING" value="true" />
+        <option name="GITBOOK_URL_ENCODING" value="false" />
+        <option name="GITHUB_LISTS" value="false" />
+        <option name="GITHUB_WIKI_LINKS" value="false" />
+        <option name="GITLAB_EXT" value="false" />
+        <option name="GITLAB_MATH_EXT" value="false" />
+        <option name="GITLAB_MERMAID_EXT" value="false" />
+        <option name="HEADER_ID_NON_ASCII_TO_LOWERCASE" value="false" />
+        <option name="HEADER_ID_NO_DUPED_DASHES" value="false" />
+        <option name="JEKYLL_FRONT_MATTER" value="false" />
+        <option name="MACROS_EXT" value="false" />
+        <option name="NO_TEXT_ATTRIBUTES" value="false" />
+        <option name="PARSE_HTML_ANCHOR_ID" value="false" />
+        <option name="PLANTUML_FENCED_CODE" value="false" />
+        <option name="PUML_FENCED_CODE" value="false" />
+        <option name="SIM_TOC_BLANK_LINE_SPACER" value="true" />
+      </ParserOptions>
+    </ParserSettings>
+    <HtmlSettings headerTopEnabled="false" headerBottomEnabled="false" bodyTopEnabled="false" bodyBottomEnabled="false" embedUrlContent="false" addPageHeader="true" embedImages="false" embedHttpImages="false" imageUriSerials="false" addDocTypeHtml="true" noParaTags="false" plantUmlConversion="0" mathConversion="0">
+      <GeneratorProvider>
+        <provider providerId="com.vladsch.idea.multimarkdown.editor.swing.html.generator" providerName="Default Swing HTML Generator" />
+      </GeneratorProvider>
+      <headerTop />
+      <headerBottom />
+      <bodyTop />
+      <bodyBottom />
+    </HtmlSettings>
+    <CssSettings previewScheme="UI_SCHEME" cssUri="" isCssUriEnabled="false" isCssUriSerial="true" isCssTextEnabled="false" isDynamicPageWidth="true">
+      <StylesheetProvider>
+        <provider providerId="com.vladsch.idea.multimarkdown.editor.swing.html.css" providerName="Default Swing Stylesheet" />
+      </StylesheetProvider>
+      <ScriptProviders />
+      <cssText />
+      <cssUriHistory />
+    </CssSettings>
+    <HtmlExportSettings updateOnSave="false" parentDir="" targetDir="" cssDir="" scriptDir="" plainHtml="false" imageDir="" copyLinkedImages="false" imageUniquifyType="0" targetPathType="2" targetExt="" useTargetExt="false" noCssNoScripts="false" useElementStyleAttribute="false" linkToExportedHtml="true" exportOnSettingsChange="true" regenerateOnProjectOpen="false" linkFormatType="HTTP_ABSOLUTE" />
+    <LinkMapSettings>
+      <textMaps />
+    </LinkMapSettings>
+  </component>
+</project>
\ No newline at end of file
diff --git a/.idea/markdown-navigator/profiles_settings.xml b/.idea/markdown-navigator/profiles_settings.xml
new file mode 100644
index 0000000..57927c5
--- /dev/null
+++ b/.idea/markdown-navigator/profiles_settings.xml
@@ -0,0 +1,3 @@
+<component name="MarkdownNavigator.ProfileManager">
+  <settings default="" pdf-export="" />
+</component>
\ No newline at end of file
diff --git a/.idea/misc.xml b/.idea/misc.xml
index 51fa3e5..cc04cd3 100644
--- a/.idea/misc.xml
+++ b/.idea/misc.xml
@@ -35,7 +35,7 @@
       </value>
     </option>
   </component>
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_1_7" project-jdk-name="1.8" project-jdk-type="JavaSDK">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_1_8" project-jdk-name="1.8" project-jdk-type="JavaSDK">
     <output url="file://$PROJECT_DIR$/build/classes" />
   </component>
   <component name="ProjectType">
diff --git a/README.md b/README.md
index 873911c..dd4456e 100644
--- a/README.md
+++ b/README.md
@@ -1,5 +1,18 @@
 # ArtGallery
-A sample android app
+A sample android app that shows how to use ViewModels and Room together with RxJava, in Kotlin by Clean Architecture.
+
+### Implemented by Clean Architecture
+The following diagram shows the structure of this project with 3 layers:
+- Presentation
+- Domain
+- Data
+
+<br>
+<p align="center">
+  <img src="https://github.com/ZahraHeydari/ArtGallery/blob/master/diagram.png" width="750"/>
+</p>
+<br>
+
 
 ### Scenario
 Used https://jsonplaceholder.typicode.com/ as a public api to generate fake data for testing
@@ -10,7 +23,7 @@ At a glance:
 - In the Item of each Album, showed user name.
 - When user taps on Album, new page will be shown which includes list of photos.
 - when user taps on photo, show image bigger through transition.
-- Were Written tests to completely cover Exceptions/Expectations(Not yet)
+- Were Written tests to completely cover Exceptions/Expectations
 - And: 
     - Supported orientation change
     - Supported offline mode
\ No newline at end of file
diff --git a/app/build.gradle b/app/build.gradle
index 1be7e7c..d21e7f0 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -64,7 +64,6 @@ dependencies {
     implementation 'com.squareup.picasso:picasso:2.71828'
     implementation 'com.android.support:design:28.0.0'
     implementation 'com.android.support:multidex:1.0.3'
-
     testImplementation 'junit:junit:4.12'
     androidTestImplementation 'com.android.support.test:runner:1.0.2'
     androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
diff --git a/app/src/androidTest/java/com/android/artgallery/data/PhotoDaoTest.kt b/app/src/androidTest/java/com/android/artgallery/data/PhotoDaoTest.kt
index d09a600..7d9057f 100644
--- a/app/src/androidTest/java/com/android/artgallery/data/PhotoDaoTest.kt
+++ b/app/src/androidTest/java/com/android/artgallery/data/PhotoDaoTest.kt
@@ -33,6 +33,12 @@ class PhotoDaoTest {
         mDatabase.close()
     }
 
+    @Test
+    @Throws(Exception::class)
+    fun isPhotoListEmpty(){
+        assertEquals(0,mDatabase.photoDao.loadAll().size)
+    }
+
 
     @Test
     @Throws(Exception::class)
diff --git a/diagram.png b/diagram.png
new file mode 100644
index 0000000..e05711d
Binary files /dev/null and b/diagram.png differ