Android constants in attrs.xml
<p>I see dimension constants declared in android attrs.xml (data/res/values/attrs.xml) such as </p>

<pre><code> &lt;attr name="padding" format="dimension" /&gt;
        &lt;!-- Sets the padding, in pixels, of the left edge; see {@link android.R.attr#padding}. --&gt;
        &lt;attr name="paddingLeft" format="dimension" /&gt;
        &lt;!-- Sets the padding, in pixels, of the top edge; see {@link android.R.attr#padding}. --&gt;
        &lt;attr name="paddingTop" format="dimension" /&gt;
        &lt;!-- Sets the padding, in pixels, of the right edge; see {@link android.R.attr#padding}. --&gt;
        &lt;attr name="paddingRight" format="dimension" /&gt;
</code></pre>

<p>If I am correct, the value is defined in
<code>./data/res/values/styles.xml</code> as       <code>&lt;item name="android:paddingLeft"&gt;20dp&lt;/item&gt;</code> etc.</p>

<p>Are these some kind of "preferred" dimension values. Are these values relatively stable between release so that the apperance wont be affect if one directly use these constants.</p>

<p>Thanks.</p>

<p>EDIT:</p>

<p>To clarify a bit, I was wondering the implication of using the these "android" defined values in my view layout, like.</p>

<pre><code> &lt;TextView android:text="@string/text"
              android:layout_width="wrap_content"
              android:layout_height="?android:attr/listPreferredItemHeightSmall"
              android:paddingStart="?android:attr/expandableListPreferredItemPaddingLeft"/&gt;
</code></pre>

<p>Instead of me defining these values, I am referring it in the android namespace. Is it safe to do so?</p>
