diff --git a/.gitignore b/.gitignore
index 9c4de58..4535beb 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,7 +1,33 @@
-.gradle
-/local.properties
-/.idea/workspace.xml
-/.idea/libraries
-.DS_Store
-/build
-/captures
+# svn
+*.svn*
+# built application files
+*.apk
+*.ap_
+# files for the dex VM
+*.dex
+# Java class files
+*.class
+# generated GUI files
+*/R.java
+# generated folder
+bin
+gen
+# local
+local.properties
+proguard_logs/
+# log files
+log*.txt
+# archives
+*.gz
+*.tar
+*.zip
+# eclipse
+*.metadata
+*.settings
+*.prefs
+#idea
+*.idea
+*.iml
+out/
+build/
+.gradle/
\ No newline at end of file
diff --git a/app/.gitignore b/app/.gitignore
index 796b96d..4535beb 100644
--- a/app/.gitignore
+++ b/app/.gitignore
@@ -1 +1,33 @@
-/build
+# svn
+*.svn*
+# built application files
+*.apk
+*.ap_
+# files for the dex VM
+*.dex
+# Java class files
+*.class
+# generated GUI files
+*/R.java
+# generated folder
+bin
+gen
+# local
+local.properties
+proguard_logs/
+# log files
+log*.txt
+# archives
+*.gz
+*.tar
+*.zip
+# eclipse
+*.metadata
+*.settings
+*.prefs
+#idea
+*.idea
+*.iml
+out/
+build/
+.gradle/
\ No newline at end of file
diff --git a/app/src/main/java/com/performance/ua/performancelab/BackgroundsActivity.java b/app/src/main/java/com/performance/ua/performancelab/BackgroundsActivity.java
index e266125..74ad037 100644
--- a/app/src/main/java/com/performance/ua/performancelab/BackgroundsActivity.java
+++ b/app/src/main/java/com/performance/ua/performancelab/BackgroundsActivity.java
@@ -21,7 +21,9 @@ protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.backgrounds_layout);
         ListView lv = (ListView) findViewById(R.id.backgrounds_list);
-        lv.setAdapter(new BackgroundListAdapter(this, 0, Arrays.asList(new String[]{"title1", "title2", "title3"})));
+        if (lv != null) {
+            lv.setAdapter(new BackgroundListAdapter(this, 0, Arrays.asList("title1", "title2", "title3")));
+        }
 
     }
 }
diff --git a/app/src/main/java/com/performance/ua/performancelab/CanvasApiView.java b/app/src/main/java/com/performance/ua/performancelab/CanvasApiView.java
index df5c55d..8bc485d 100644
--- a/app/src/main/java/com/performance/ua/performancelab/CanvasApiView.java
+++ b/app/src/main/java/com/performance/ua/performancelab/CanvasApiView.java
@@ -33,10 +33,15 @@ public CanvasApiView(Context context, AttributeSet attrs, int defStyleAttr) {
     protected void onDraw(Canvas canvas) {
         super.onDraw(canvas);
         for (int i = 0; i < N; i++) {
+            canvas.save();
+            if (i != N - 1) {
+                canvas.clipRect(MARGIN + i * shift, MARGIN, MARGIN + i * shift + shift, SIZE);
+            }
             // Each card is laid out a little to the right of the previous one.
             myPaint.setColor(Color.RED / (i + 1));
             myPaint.setStrokeWidth(10);
             canvas.drawRect(MARGIN + i * shift, MARGIN, SIZE + i * shift, SIZE, myPaint);
+            canvas.restore();
         }
         // Invalidate the whole view. Doing this calls onDraw() if the view is visible.
         invalidate();
diff --git a/app/src/main/res/layout/backgrounds_layout.xml b/app/src/main/res/layout/backgrounds_layout.xml
index 031a411..d36753e 100644
--- a/app/src/main/res/layout/backgrounds_layout.xml
+++ b/app/src/main/res/layout/backgrounds_layout.xml
@@ -2,18 +2,18 @@
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
     android:orientation="vertical" android:layout_width="match_parent"
     android:layout_height="match_parent"
-    android:background="@android:color/white">
+    >
 
     <TextView
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:text="@string/backgrounds_title"
-        android:background="@android:color/white"/>
+        />
 
     <ListView
         android:layout_width="match_parent"
         android:layout_height="match_parent"
         android:id="@+id/backgrounds_list"
-        android:background="@android:color/white"/>
+        />
 
 </LinearLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/canvas_layout.xml b/app/src/main/res/layout/canvas_layout.xml
index 3e480b0..515f9c3 100644
--- a/app/src/main/res/layout/canvas_layout.xml
+++ b/app/src/main/res/layout/canvas_layout.xml
@@ -1,10 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
-    android:orientation="vertical" android:layout_width="match_parent"
-    android:layout_height="match_parent">
-
-    <com.performance.ua.performancelab.CanvasApiView
-        android:layout_width="match_parent"
-        android:layout_height="match_parent" />
-
-</LinearLayout>
\ No newline at end of file
+<com.performance.ua.performancelab.CanvasApiView
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"/>
diff --git a/app/src/main/res/layout/hierarchy_layout.xml b/app/src/main/res/layout/hierarchy_layout.xml
index 94440c0..837a65b 100644
--- a/app/src/main/res/layout/hierarchy_layout.xml
+++ b/app/src/main/res/layout/hierarchy_layout.xml
@@ -1,38 +1,30 @@
 <?xml version="1.0" encoding="utf-8"?>
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
-    android:layout_width="match_parent"
-    android:layout_height="wrap_content"
-    android:orientation="vertical">
+              android:layout_width="match_parent"
+              android:layout_height="wrap_content"
+              android:layout_marginTop="@dimen/activity_vertical_margin"
+              android:orientation="horizontal">
 
-    <!-- Version 1. Uses nested LinearLayouts -->
-    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    <ImageView
+        android:id="@+id/chat_author_avatar1"
+        android:layout_width="@dimen/avatar_dimen"
+        android:layout_height="@dimen/avatar_dimen"
+        android:layout_margin="@dimen/avatar_layout_margin"
+        android:src="@mipmap/ic_launcher"/>
+
+    <LinearLayout
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
-        android:layout_marginTop="@dimen/activity_vertical_margin"
-        android:orientation="horizontal">
-
-        <ImageView
-            android:id="@+id/chat_author_avatar1"
-            android:layout_width="@dimen/avatar_dimen"
-            android:layout_height="@dimen/avatar_dimen"
-            android:layout_margin="@dimen/avatar_layout_margin"
-            android:src="@mipmap/ic_launcher" />
+        android:orientation="vertical">
 
-        <LinearLayout
+        <TextView
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
-            android:orientation="vertical">
-
-            <TextView
-                android:layout_width="match_parent"
-                android:layout_height="wrap_content"
-                android:text="@string/line1_text" />
+            android:text="@string/line1_text"/>
 
-            <TextView
-                android:layout_width="match_parent"
-                android:layout_height="wrap_content"
-                android:text="@string/line2_text" />
-        </LinearLayout>
+        <TextView
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:text="@string/line2_text"/>
     </LinearLayout>
-
 </LinearLayout>
\ No newline at end of file