Why is NumberPicker (up-down-domain picker) not visibility in Android UI Editor at Eclipse?
<p>up-down-domain picker is a popular/general UI component, but anytime I have to add it by hand.Why is NumberPicker (up-down-domain picker) not visibility in Android UI Editor at Eclipse?</p>

<pre><code>&lt;android.widget.NumberPicker
android:id="@+id/ppp"
android:layout_width="wrap_content"
android:layout_height="wrap_content" /&gt;
</code></pre>

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<p>I got it! NumberPicker widget supports Android SDK since API level 11 = Android 3.0+ OS, and my project is based on Android 2.x OS. </p>
