android - Listview item smaller than screen width so the activity background is visible on the sides -

i need know how modify list items layout don't fill screen width , activity background visible on sides.

i tried various layout_width no success.

i want know how it, i'll apply rule in case

edit: xml code of list item

<?xml version="1.0" encoding="utf-8"?> <linearlayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="center_horizontal" android:orientation="vertical"  android:layout_marginleft="20dp"  android:cliptopadding="true" android:background="#ffffff" >  <linearlayout android:layout_width="match_parent" android:layout_height="wrap_content" >  <imageview     android:id="@+id/post_logo"     android:layout_width="wrap_content"     android:layout_height="wrap_content"     android:src="@drawable/ic_post" />  <linearlayout     android:layout_width="wrap_content"     android:layout_height="match_parent"     android:orientation="vertical" >      <textview         android:id="@+id/post_nick"         android:layout_width="wrap_content"         android:layout_height="wrap_content"         android:textappearance="?android:attr/textappearancelarge" />      <textview         android:id="@+id/post_date"         android:layout_width="wrap_content"         android:layout_height="wrap_content"         android:textappearance="?android:attr/textappearancesmall" />  </linearlayout>  </linearlayout>  <textview android:id="@+id/post_content" android:layout_width="match_parent" android:layout_height="wrap_content" android:textsize="15sp" android:paddingtop="5dp" android:paddingbottom="5dp" android:paddingleft="5dp" android:paddingright="5dp" android:textappearance="?android:attr/textappearancemedium" />  </linearlayout> 

you can set android:layout_marginleft , android:layout_marginright on listview (in xml) set minimum margin between listview , screen sides.