Android :: Buttons OnClick Event Fails To Fire?

I have an activity, where the ListView holds customized linear layout elements for each row. One of the rows has a button defined as:

<Button
android:text="Pick a contact"
android:id="@+id/btnPickContact"
android:layout_width="wrap_content"
android:gravity="center_vertical"
android:layout_height="wrap_content"></Button>

Then in java, I have this code:...............