attrs.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <declare-styleable name="NumberPicker">
        <attr name="picker_stepSize" format="integer" />
        <attr name="picker_min" format="integer" />
        <attr name="picker_max" format="integer" />
        <attr name="picker_arrowStyle" format="reference" />
        <attr name="picker_editTextStyle" format="reference" />
        <attr name="picker_tooltipAnimationStyle" format="reference" />
        <attr name="picker_tooltipStyle" format="reference" />
        <attr name="picker_disableTooltip" format="boolean" />
        <attr name="picker_disableGestures" format="boolean" />
        <attr name="android:progress" />

        <attr name="picker_tracker" format="enum">
            <enum name="linear" value="0" />
            <enum name="exponential" value="1" />
        </attr>

        <attr name="picker_orientation" format="enum">
            <enum name="horizontal" value="0" />
            <enum name="vertical" value="1" />
        </attr>

        <attr name="android:background" />

    </declare-styleable>

    <attr name="pickerStyle" format="reference" />

</resources>