Question

I have a very simple problem, but I am clearly doing something wrong. I’ve tried many ways to do this, but there’s always something screwing up.

I have a ListView with a horizontal LinearLayout serving as a header. I want to have < and > serving as “back and next” widgets, on the very left and very right portions of the LinearLayout. The LIST HEADER portion should be centered between them.

Making LIST HEADER have the attribute android:layout_width="match_parent" cuts off the right hand arrow. Otherwise it lays on top of the left arrow, even though it appears after the LIST HEADER TextView in the XML file.

<     LIST HEADER     >
List item number 1
List item number 2
List item number 3

I’m not new to Android at this stage but this seems basic. Any help would be appreciated.
I should add that I’m not using eclipse.

CURRENT XML (sort of messy after trying so many things, apologies):

<LinearLayout
android:orientation="vertical"  
android:layout_width="match_parent"
android:layout_height="match_parent">

  <LinearLayout
  android:orientation="horizontal"
  android:gravity="center"
  android:layout_width="match_parent"
  android:layout_height="wrap_content">
<RelativeLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent">

  <RelativeLayout
      android:id="@+id/LeftFormulaHeaderLayout"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content">
  <TextView
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_gravity="left"
      android:textSize="@dimen/text_huge"
      android:id="@+id/LeftFormulaHeader"
      android:text="&lt;"/>
  </RelativeLayout>
  <TextView
      android:layout_width="200dip"
      android:layout_height="wrap_content"
      android:textSize="@dimen/text_huge"
      android:ellipsize="end"
      android:scrollHorizontally="false"
      android:singleLine="true"
      android:gravity="center"
      android:id="@+id/FormulaHeader"/>

  <RelativeLayout
      android:id="@+id/RightFormulaHeaderLayout"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content">
    <TextView
    android:id="@+id/RightFormulaHeader"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_gravity="right"
    android:textSize="@dimen/text_huge"
    android:text="&gt;"/>
  </RelativeLayout>
</RelativeLayout>
</LinearLayout>


  <ListView
  android:id="@+id/TheList"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:background="#000033"
  android:layout_weight="1"
  android:drawSelectorOnTop="false" />

  <TextView
      android:id="@+id/empty_list_item"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:visibility="gone"
      android:text="@string/empty_list" />
</LinearLayout>

Answer 1

Your main issue: gravity affects positioning of the text within the TextView. You want alignParentLeft/-Right and centerHorizontal for what you are doing (although gravity="center" remains to keep the header centered in its view).

<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent">

<TextView
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:layout_alignParentLeft="true"
  android:textSize="@dimen/text_huge"
  android:id="@+id/LeftFormulaHeader"
  android:text="&lt;"/>
<TextView
  android:layout_width="200dip"
  android:layout_height="wrap_content"
  android:textSize="@dimen/text_huge"
  android:ellipsize="end"
  android:scrollHorizontally="false"
  android:singleLine="true"
  android:layout_centerHorizontal="true"
  android:gravity="center"
  android:id="@+id/FormulaHeader"
  android:text="HEADER"/>

<TextView
android:id="@+id/RightFormulaHeader"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:textSize="@dimen/text_huge"
android:text="&gt;"/>
</RelativeLayout>