Android Layout Transparent Circle on Map

Question

I'm trying to make this progress bar transparent as in the image below, on top of a map to give that effect. Someone Tip. Any tips on how to achieve this effect?

Code Activity:

<fragment xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:map="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/map"
android:name="com.google.android.gms.maps.SupportMapFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="drive.uberclone.com.uberdrive.MapsActivity" >

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/activity_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <ProgressBar
        android:id="@+id/progressBarCircle"
        style="?android:attr/progressBarStyleHorizontal"
        android:layout_width="270dp"
        android:layout_height="270dp"
        android:layout_centerInParent="true"
        android:background="@drawable/drawable_circle_dark_blue"
        android:indeterminate="false"
        android:max="100"
        android:progress="100"
        android:progressDrawable="@drawable/drawable_circle_yellow"
        android:rotation="-90" />

    <TextView
        android:id="@+id/textViewTime"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerInParent="true"
        android:text="00:01:00"
        android:visibility="visible"
        android:textColor="@color/colorYellow"
        android:textSize="40sp" />


</RelativeLayout>