<FrameLayout 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"
    tools:context="tw.wancw.curator.MeiZiCardsFragment">

    <GridView
        android:id="@+id/cards"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:numColumns="2"
        tools:listitem="@layout/view_meizicard" />

    <ProgressBar
        android:id="@+id/loading_indicator"
        style="@android:style/Widget.ProgressBar.Horizontal"
        android:layout_width="match_parent"
        android:layout_height="3dp"
        android:indeterminate="true" />

</FrameLayout>

<FrameLayout 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"
    tools:context="tw.wancw.curator.MeiZiCardsFragment">

    <GridView
        android:id="@+id/cards"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:numColumns="2"
        tools:listitem="@layout/view_meizicard" />

    <ProgressBar
        android:id="@+id/loading_indicator"
        style="@android:style/Widget.ProgressBar.Horizontal"
        android:layout_width="match_parent"
        android:layout_height="10dp"
        android:layout_gravity="bottom"
        android:indeterminate="true" />

</FrameLayout>

Move "loading bar" to bottom and make it more obvious.
Move "loading bar" to bottom and make it more obvious.
