Android Layout Margin

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/homeBgColor"
    android:orientation="vertical" >

    <TextView
        style="@style/CodeFont"
        android:layout_width="match_parent"
        android:background="@color/homeTitleBgColor"
        android:gravity="center"
        android:text="@string/home"
        android:textColor="@color/homeTitleColor"
        android:textSize="27dp"
        android:textStyle="bold"
        android:padding="10dp"
        android:layout_margin="0dp"
        tools:context=".Home" />

    <ImageView
        android:id="@+id/imageView1"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="0.31"
        android:contentDescription="@string/homePageImage"
        android:gravity="center"
        android:src="@drawable/jaltucher" />

    <TextView
        android:id="@+id/read_article"
        style="@style/CodeFont"
        android:background="@drawable/custom_button"
        android:gravity="center"
        android:text="@string/read"
        android:textColor="@color/homeTextColor"
        tools:context=".Home" />

    <TextView
        android:id="@+id/contact_james"
        style="@style/CodeFont"
        android:background="@drawable/custom_button"
        android:gravity="center"
        android:text="@string/contact_james"
        android:textColor="@color/homeTextColor"
        tools:context=".Home" />

    <TextView
        android:id="@+id/about_inventika"
        style="@style/CodeFont"
        android:gravity="center"
        android:text="@string/about"
        android:textColor="@color/homeTextColor"
        android:background="@drawable/custom_button"
        tools:context=".Home" />

</LinearLayout>