Hi
I make a layout-land folder and make a main.xml.It should show the layout when I change the layout to landscape but it is showing the original layout.

this the code of main.xml in layout-land

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
<Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="sudesh"/>
</LinearLayout>

and this is the code of mail.xml in layout

<RelativeLayout 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">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/hello_world" />
</RelativeLayout>

what can be reason?

mail.xml (or) main.xml ???

Must be the same file name (main.xml) in both layout-land and layout folders. In java file, just call setContentView(R.layout.main);