Question

I have a header for a list that contains two image buttons. I want one of those image buttons to be on the left, and the other to be on the right. This is what my xml file looks like right now but it does not work, it just puts the two image buttons on the left together. I have also tried without the additional LinearLayouts but no luck.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
  android:orientation="horizontal"
  android:gravity="fill_horizontal"
  android:background="@drawable/list_header_background">
    <LinearLayout
      xmlns:android="http://schemas.android.com/apk/res/android"
      android:layout_width="wrap_content"
      android:layout_height="fill_parent"
      android:orientation="horizontal"
      android:gravity="left"
      android:background="@drawable/list_header_background">
        <ImageButton
            android:id="@+id/refreshBtn"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:padding="4dp"
            android:src="@drawable/ic_refresh"
            android:background="@drawable/list_header_background"
            />
    </LinearLayout>
    <LinearLayout
      xmlns:android="http://schemas.android.com/apk/res/android"
      android:layout_width="wrap_content"
      android:layout_height="fill_parent"
      android:orientation="horizontal"
      android:gravity="right"
      android:background="@drawable/list_header_background">
        <ImageButton
            android:id="@+id/battleBtn"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:padding="4dp"
            android:src="@drawable/ic_battle"
            android:background="@drawable/list_header_background"
            />
    </LinearLayout>
</LinearLayout>

Answer 1

As kabuko wrote, the RelativeLayout width is equal to the parent width. When we have a child view inside that RelativeLayout, we can use the android:layout_alignParentXXXXXX="true" parameter in order to align it (the child) accordingly to the parent.

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
  android:orientation="horizontal"
  android:background="@drawable/list_header_background">
  <ImageButton
      android:id="@+id/refreshBtn"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:padding="4dp"
      android:src="@drawable/ic_refresh"
      android:layout_alignParentLeft="true"
      android:background="@drawable/list_header_background"
  />
  <ImageButton
      android:id="@+id/battleBtn"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:padding="4dp"
      android:src="@drawable/ic_battle"
      android:layout_alignParentRight="true"
      android:background="@drawable/list_header_background"
   />
</RelativeLayout>