I just found out that you can change it using setImageResource.
Thank you guys.
Pergunta
How can I change my "Pin It" icon? Android:src on the xml file doesn't work.
<com.pinterest.pinit.PinItButton
android:id="@+id/pin_bt"
android:src="@drawable/ic_launcher"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="@dimen/global_padding" />
Solução
I just found out that you can change it using setImageResource.
Thank you guys.