How to set elevation for circle imageview?

<ImageView
    android:elevation="5dp"
    android:id="@+id/fragment_user_profile_avatar"
    android:layout_width="match_parent"
    android:layout_height="305dp"
    android:scaleType="centerCrop"
    android:layout_alignParentTop="true"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true"
    android:background="@color/feed_bg" />

<TextView
    android:elevation="6dp"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:textAppearance="?android:attr/textAppearanceMedium"
    android:id="@+id/user_name"
    android:text="Hello This is a TextView"
    android:textColor="#ffffffff"
    android:textSize="28sp"
    android:fontFamily="roboto-regular"
    android:layout_centerVertical="true"
    android:layout_centerHorizontal="true" />

android:elevation="2dp"    
android:background="@drawable/myrect"

<!-- res/drawable/myrect.xml -->
<shape xmlns:android="http://schemas.android.com/apk/res/android"
       android:shape="rectangle">
    <solid android:color="#42000000" />
    <corners android:radius="5dp" />
</shape>

OkHttpClient client = new OkHttpClient();

String getElevation(String url) throws IOException {
  Request request = new Request.Builder()
      .url(url)
      .build();

  Response response = client.newCall(request).execute();
  return response.body().string();
}