Android: message font size in alertdialog through styles
<p>I'm trying to change font size of message in alert dialog through styles but I can't make it work. There is a lot of answers describing how to do this but almost all of them I found do it programmatically. I want to do this once in styles, not with every new alertdialog.</p>

<p>What I've done so far:</p>

<p>In <code>\AndroidSDK\platforms\android-23\data\res\layout\alert_dialog.xml</code> I see the TextView that is showing the message:</p>

<pre><code>&lt;TextView android:id="@+id/message"
    style="?android:attr/textAppearanceMedium"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:padding="5dip" /&gt;
</code></pre>

<p>In <code>\AndroidSDK\platforms\android-23\data\res\values\themes.xml</code> I see that the value of <code>textAppearanceMedium</code> attribute is <code>@style/TextAppearance.Medium</code>.</p>

<p>I've created a following style of which the parent is <code>TextAppearance.AppCompat.Medium</code>. This style is then applied to <code>android:textAppearanceMedium</code> attribute of AlertDialog's style as follows:</p>

<pre><code>&lt;style name="Theme.My" parent="Theme.AppCompat.Light.NoActionBar.FullScreen"&gt;
    &lt;item name="android:alertDialogTheme"&gt;@style/Theme.My.AlertDialog&lt;/item&gt;
&lt;/style&gt;

&lt;style name="Theme.My.AlertDialog" parent="Theme.AppCompat.Light.Dialog.Alert"&gt;
    &lt;item name="android:textAppearanceMedium"&gt;@style/MyTextAppearanceMedium&lt;/item&gt;
&lt;/style&gt;

&lt;style name="MyTextAppearanceMedium" parent="TextAppearance.AppCompat.Medium"&gt;
    &lt;item name="android:textSize"&gt;24sp&lt;/item&gt;
&lt;/style&gt;
</code></pre>

<p>...but the font size won't change. What's wrong? </p>

<p>I'm using AppCompat support lib, min SDK 16, target SDK 23.</p>

<p>Thank you.</p>