I Just created one LinearLayout with WeightSum and put Button inside it. but my Button is taking space without I apply any style or property is not work as i expected.
xml code :
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_gravity="center_horizontal"
android:background="#FFFFFF"
android:orientation="horizontal">
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:orientation="horizontal">
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#e6e6e6"
android:orientation="vertical"
android:weightSum="13.0">
<Button
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1.0"
android:gravity="center"
android:text="T"
android:textColor="#000000"/>
<Button
android:layout_width="wrap_content"
android:layout_height="0dp"
android:layout_weight="1.0"
android:gravity="center"
android:text="A"
android:textColor="#000000"/>
<Button
android:layout_width="wrap_content"
android:layout_height="0dp"
android:layout_weight="1.0"
android:gravity="center"
android:text="J"
android:textColor="#000000"/>
<Button
android:layout_width="wrap_content"
android:layout_height="0dp"
android:layout_weight="1.0"
android:gravity="center"
android:text="R"
android:textColor="#000000"/>
<Button
android:layout_width="wrap_content"
android:layout_height="0dp"
android:layout_weight="1.0"
android:gravity="center"
android:text="D"
android:textColor="#000000"/>
<Button
android:layout_width="wrap_content"
android:layout_height="0dp"
android:layout_weight="1.0"
android:gravity="center"
android:text="K"
android:textColor="#000000"/>
<Button
android:layout_width="wrap_content"
android:layout_height="0dp"
android:layout_weight="1.0"
android:gravity="center"
android:text="I"
android:textColor="#000000"/>
<Button
android:layout_width="wrap_content"
android:layout_height="0dp"
android:layout_weight="1.0"
android:gravity="center"
android:text="E"
android:textColor="#000000"/>
<Button
android:layout_width="wrap_content"
android:layout_height="0dp"
android:layout_weight="1.0"
android:gravity="center"
android:text="F"
android:textColor="#000000"/>
<Button
android:layout_width="wrap_content"
android:layout_height="0dp"
android:layout_weight="1.0"
android:gravity="center"
android:text="G"
android:textColor="#000000"/>
<Button
android:layout_width="wrap_content"
android:layout_height="0dp"
android:layout_weight="1.0"
android:gravity="center"
android:text="H"
android:textColor="#000000"/>
<Button
android:layout_width="wrap_content"
android:layout_height="0dp"
android:layout_weight="1.0"
android:gravity="center"
android:text="L"
android:textColor="#000000"/>
<Button
android:layout_width="wrap_content"
android:layout_height="0dp"
android:layout_weight="1.0"
android:gravity="center"
android:text="C"
android:textColor="#000000"/>
</LinearLayout>
</LinearLayout>
</LinearLayout>
Output ScreenShot :
