View is the base class for widgets in Android which are used to create UI components like buttons and text fields. The ViewGroup subclass of View provides an invisible container to hold other views and view groups and define their layout properties. Examples provided demonstrate how to use FrameLayout and RelativeLayout to position views in relation to each other within their containers.

7.  View is the base class for widgets, which are used to create interactive UI
components like buttons, text fields, etc.
 The ViewGroup is a subclass of View and provides invisible container that hold
otherViews or otherViewGroups and define their layout properties.

36.  <FrameLayout
xmlns:android="http://schemas.android.com/apk/res/androi
d"
 android:layout_width="fill_parent"
 android:layout_height="fill_parent">
 <ImageView
 android:src="@drawable/ic_launcher"
 android:scaleType="fitCenter"
 android:layout_height="250px"
 android:layout_width="250px"/>
 <TextView
 android:text="Frame Demo"
 android:textSize="30px"
 android:textStyle="bold"
 android:layout_height="fill_parent"
 android:layout_width="fill_parent"
 android:gravity="center"/>
 </FrameLayout>

53.  <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
 android:orientation="vertical"
 android:layout_width="match_parent"
 android:layout_height="match_parent">
 <Button
 android:id="@+id/Apple"
 android:text="Apple"
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:layout_marginTop="15dip"
 android:layout_marginLeft="20dip" />
 <Button
 android:id="@+id/Mango"
 android:text="Mango"
 android:layout_width="match_parent"
 android:layout_height="wrap_content"
 android:padding="28dip"
 android:layout_toRightOf="@id/Apple"
 android:layout_marginLeft="15dip"
 android:layout_marginRight="10dip"
 android:layout_alignParentTop="true" />
 <Button
 android:id="@+id/Banana"
 android:text="Banana"
 android:layout_width="200dip"
 android:layout_height="50dip"
 android:layout_marginTop="15dip"
 android:layout_below="@id/Apple"
 android:layout_alignParentLeft="true" />
 <Button
 android:id="@+id/Grapes"
 android:text="Grapes"
 android:layout_width="wrap_content"
 android:layout_height="match_parent"
 android:minWidth="100dp"
 android:layout_alignParentRight="true"
 android:layout_below="@id/Banana" />
 <Button
 android:id="@+id/Kiwi"
 android:text="Kiwi"
 android:layout_width="100dip"
 android:layout_height="wrap_content"