title: Android Listview not shown in relative layout
body: <p>I have a relative layout to show a menu with some buttons and edittext. This is displayed fine.
  When I add a listview to a parent relative layout (to display the listview below the menu layout), but the listview is not shown.
  My XML code is inserted below.</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
      android:layout_width="fill_parent"
      android:layout_height="fill_parent" &gt;
  
      &lt;fragment
          android:id="@+id/map"
          android:name="com.google.android.gms.maps.MapFragment"
          android:layout_width="match_parent"
          android:layout_height="wrap_content" /&gt;
  
      &lt;RelativeLayout
          android:id="@+id/listactivity"
          android:layout_width="match_parent"
          android:layout_height="match_parent" &gt;
  
      &lt;RelativeLayout
          android:id="@+id/menu"
          android:layout_width="match_parent"
          android:layout_height="75dp"
          android:background="#ff0000"
          android:orientation="vertical"
          android:focusableInTouchMode="true" 
          android:layout_gravity="top" &gt;
  
          &lt;Button
              android:id="@+id/cities"
              android:layout_width="wrap_content"
              android:layout_height="wrap_content"
              android:text="Cities"
              android:textStyle="bold"
              android:onClick="showPopup" /&gt;
  
      &lt;Button
          android:id="@+id/addcity"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:minWidth="30dp"
          android:text="+"
          android:textStyle="bold"
          android:layout_toRightOf="@+id/cities" /&gt;
  
      &lt;Button
          android:id="@+id/days"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:text="Days"
          android:textStyle="bold"
          android:layout_toRightOf="@+id/addcity" /&gt;
  
      &lt;Button
          android:id="@+id/addday"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:layout_toRightOf="@+id/days"
          android:minWidth="30dp"
          android:text="+"
          android:textStyle="bold" /&gt;
  
      &lt;Button
          android:id="@+id/Days"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:text=""
          android:layout_toRightOf="@+id/addday"
          android:textStyle="bold"
          android:onClick="showListview" /&gt;
  
      &lt;EditText
          android:id="@+id/myEditText"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:layout_weight="1"
          android:layout_below="@+id/cities"
          android:ems="10" &gt;
      &lt;/EditText&gt;
  
  &lt;/RelativeLayout&gt;
  
      &lt;ListView
          android:id="@+id/listview"
          android:background="#fff000"
          android:layout_width="150dp"
          android:layout_height="wrap_content"
          android:visibility="visible"
          android:layout_below="@+id/menu" /&gt;
  
  &lt;/RelativeLayout&gt;
  </code></pre>
  
  <p></p>