What is the best way to add a button to the bottom right corner in my app with the maps, and change this button in different states like in GoogleMaps? I am using OSMDroid and need add custom button, not default.
use this layout and it get you what you are looking for
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<fragment
android:id="@+id/map"
android:layout_width="match_parent"
android:layout_height="match_parent" />
<ImageView
android:id="@+id/imageViewFlagPassenger"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:background="@android:color/transparent"
android:src="@drawable/marker" />
<ImageView
android:id="@+id/btn_passenger_current_location"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentRight="true"
android:layout_marginBottom="20dp"
android:layout_marginRight="10dp"
android:background="@drawable/location_icon" />
</RelativeLayout>
</LinearLayout>