Add gradient to imageview

I want to add a gradient on the bottom of my image . Something like this :

I tried something like this but I only get the gradient no image..

    <ImageView
    android:id="@+id/trendingImageView"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:background="@drawable/trend_donald_sterling"
    android:src="@drawable/trending_gradient_shape"
  />

trending_gradient_shape:

<shape xmlns:android="http://schemas.android.com/apk/res/android"
       android:shape="rectangle" >

    <gradient
        android:angle="90"
        android:endColor="@android:color/darker_gray"
        android:startColor="@android:color/darker_gray" />

    <corners android:radius="0dp" />

</shape>

You need two layers: An ImageView, and a View on top of that with your gradient as android:background. Put these two Views in a FrameLayout:

<FrameLayout
    ... >

    <ImageView
        ...
        android:src="@drawable/trend_donald_sterling" />

    <View
        ...
        android:background="@drawable/trending_gradient_shape"/>


</FrameLayout>