Develop Reference

Theme.MaterialComponents does not change font of dialog title

I am using the material components theming for our app. Now we want a custom font, which I managed to apply almost everywhere with the theme below, which uses the various textAppearance... attributes defined by material components.
This works very well, and the theme is also applied to the AlertDialogs almost everywhere -- message text and buttons have the custom font, buttons have the correct accent colors etc.
Only the dialog title keeps the Roboto font, no matter what.
<!-- externalized font name for easier change -->
<string name="font_regular" translatable="false" tools:ignore="ReferenceType">#font/atma_regular</string>
<style name="Theme.App" parent="Theme.MaterialComponents.Light.NoActionBar">
<item name="colorPrimary">#color/colorPrimary</item>
<item name="colorPrimaryDark">#color/colorPrimaryDark</item>
<item name="colorAccent">#color/colorAccent</item>
<item name="android:textColorPrimary">#color/textColorPrimary</item>
<item name="android:textColorSecondary">#color/textColorSecondary</item>
<item name="textAppearanceHeadline1">#style/TextAppearance.App.Button</item>
<item name="textAppearanceHeadline2">#style/TextAppearance.App.Button</item>
<item name="textAppearanceHeadline3">#style/TextAppearance.App.Button</item>
<item name="textAppearanceHeadline4">#style/TextAppearance.App.Button</item>
<item name="textAppearanceHeadline5">#style/TextAppearance.App.Button</item>
<item name="textAppearanceHeadline6">#style/TextAppearance.App.Button</item>
<item name="textAppearanceSubtitle1">#style/TextAppearance.App.Subtitle1</item>
<item name="textAppearanceSubtitle2">#style/TextAppearance.App.Subtitle2</item>
<item name="textAppearanceBody1">#style/TextAppearance.App.Body1</item>
<item name="textAppearanceBody2">#style/TextAppearance.App.Body2</item>
<item name="textAppearanceButton">#style/TextAppearance.App.Button</item>
<item name="android:textAppearanceLarge">#style/TextAppearance.App.Large</item>
<item name="android:textAppearanceMedium">#style/TextAppearance.App.Medium</item>
<item name="android:textAppearanceSmall">#style/TextAppearance.App.Small</item>
</style>
<style name="TextAppearance.App.Subtitle1" parent="TextAppearance.MaterialComponents.Subtitle1">
<item name="fontFamily">#string/font_regular</item>
<item name="android:fontFamily">#string/font_regular</item>
</style>
...
I tried to define an extra theme for the alert dialogs like so:
<style name="Theme.App" parent="Theme.MaterialComponents.Light.NoActionBar">
...
<item name="alertDialogTheme">#style/Theme.App.AlertDialog</item>
...
</style>
<style name="Theme.App.AlertDialog" parent="Theme.MaterialComponents.Light.Dialog.Alert">
<item name="android:windowTitleStyle">#style/TextAppearance.App.DialogWindowTitle</item>
</style>
<style name="TextAppearance.App.DialogWindowTitle" parent="ThemeOverlay.MaterialComponents.Dialog.Alert">
<item name="fontFamily">#string/font_regular</item>
<item name="android:fontFamily">#string/font_regular</item>
<item name="android:textSize">30sp</item>
</style>
But that resets the colors and fonts everywhere. The only thing that is applied, is the textSize.
It really shouldn't be so hard to achieve this, but I am out of ideas right now. I could apply the font programmatically, but that would be quite ugly.

As you mentioned the AlertDialog created by MaterialAlertDialogBuilder uses the style defined by the textAppearanceSubtitle1 attribute in your app theme.
Otherwise you can change the style used by the AlertDialog using something like:
new MaterialAlertDialogBuilder(MainActivity.this,
R.style.MyTitle_ThemeOverlay_MaterialComponents_MaterialAlertDialog)
.setTitle("Title")
.setMessage("Message......")
.setPositiveButton("ok", null)
.setNegativeButton("Cancel", null)
.show();
In your style you have to customize the materialAlertDialogTitleTextStyle attribute:
<style name="MyTitle_ThemeOverlay.MaterialComponents.MaterialAlertDialog" parent="#style/ThemeOverlay.MaterialComponents.MaterialAlertDialog">
<item name="materialAlertDialogTitleTextStyle">#style/MyTitle_MaterialAlertDialog.MaterialComponents.Title.Text</item>
</style>
<style name="MyTitle_MaterialAlertDialog.MaterialComponents.Title.Text" parent="#style/MaterialAlertDialog.MaterialComponents.Title.Text">
<item name="android:textAppearance">#style/MyTitle_TextAppearance.MaterialComponents.Subtitle1</item>
</style>
<style name="MyTitle_TextAppearance.MaterialComponents.Subtitle1" parent="TextAppearance.MaterialComponents.Subtitle1">
<item name="fontFamily">....</item>
<item name="android:fontFamily">....</item>
<item name="android:textStyle">.....</item>
</style>

Thanks to your question I realized that I was using the incorrect attribute to assign the title style (android:titleTextAppearance instead of android:windowTitleStyle).
It looks like your issue has been fixed in the meantime, as your exact code seems to work for me as of today.

Change color of frame around the dialog title in Android

I want to change the background of alert dialog title in theme.
I do following changes in theme:
<style name="NgTheme" parent="#android:style/Theme.Holo.Light">
<item name="android:dialogTheme">#style/NgDialogTheme</item>
<item name="android:alertDialogTheme">#style/NgAlertDialogTheme</item>
</style>
<style name="NgDialogTheme" parent="#android:style/Theme.Holo.Light.Dialog">
<item name="android:background">#android:color/transparent</item>
<item name="android:windowTitleStyle">#style/NgWindowTitleStyle</item>
</style>
<style name="NgAlertDialogTheme" parent="#style/NgDialogTheme">
</style>
<style name="NgWindowTitleStyle" parent="android:TextAppearance.Holo.DialogWindowTitle">
<item name="android:background">#318d99</item>
<item name="android:textColor">#fff</item>
</style>
I expected that background of title becomes #318d99. But only background of text is #318d99:
How can I change white frame around the title to #318d99?
Also the frame around the dialog isn't transparent. How can I fix it?

There are some valuable posts about this already and very closely related to your question.
Google's post on customizing this is possibly worth looking at first:
https://sites.google.com/site/androidhowto/how-to-1/customize-alertdialog-theme
Take a look at this blog post:
http://blog.supenta.com/2014/07/02/how-to-style-alertdialogs-like-a-pro/
Specifically, go to Part 5: Styling the Background.
To summarize, they suggest that you will probably have to
Stop inheriting from Holo
Give your main theme an alertDialogStyle
Then create a style with the following attributes, which you can get a reference to here: http://developer.android.com/reference/android/R.styleable.html#AlertDialog
You'll want to create a new style that inherits from the default alertdialog theme (this is discussed in both posts I mentioned above):
<style name="CustomDialogTheme" parent="#android:style/Theme.Dialog">
<item name="android:bottomBright">#color/white</item>
<item name="android:bottomDark">#color/white</item>
<item name="android:bottomMedium">#color/white</item>
<item name="android:centerBright">#color/white</item>
<item name="android:centerDark">#color/white</item>
<item name="android:centerMedium">#color/white</item>
<item name="android:fullBright">#color/orange</item>
<item name="android:fullDark">#color/orange</item>
<item name="android:topBright">#color/blue</item>
<item name="android:topDark">#color/blue</item>
</style>

Alternative Layouts

I am developing an android application that I want to support Material Design for devices running 5.0+ and devices from 4.1 to 4.4.
I am using the appcompat library to get some support for older versions.
Now I am faced with attributes that are only present in v21, like elevation.
I can create a layout-v21 folder and add my activity's layout there, again, which leads to quite a bit of duplication.
Do you do this another way?
Is there a way to use styles for this? How do I subclass a style from values to values-v21

Here is a link that I have used that gives some information about overriding styles/themes for v21 Lollipop: http://antonioleiva.com/material-design-everywhere/
Essentially you can do in values/themes.xml
<style name="AppTheme" parent="AppTheme.Base"/>
<style name="AppTheme.Base" parent="Theme.AppCompat">
<item name="colorPrimary">#color/colorPrimary</item>
<item name="colorPrimaryDark">#color/colorPrimary</item>
<item name="android:windowNoTitle">true</item>
<item name="windowActionBar">false</item>
</style>
And then in values-v21/themes.xml
<style name="AppTheme" parent="AppTheme.Base">
<item name="android:windowContentTransitions">true</item>
<item name="android:windowAllowEnterTransitionOverlap">true</item>
<item name="android:windowAllowReturnTransitionOverlap">true</item>
<item name="android:windowSharedElementEnterTransition">#android:transition/move</item>
<item name="android:windowSharedElementExitTransition">#android:transition/move</item>
</style>
To override AppTheme for v21 but to retain all the properties for the AppTheme.Base from pre-v21.

ActionBarSherlock: changing homeAsUpIndicator doesn't work

I'm want to change the up icon with applying the following style to my activity, but it doesn't work and but I still get the default black '<' icon.
Can anyone find out what is missing here?
<style name="AppTheme.ActionBar" parent="#style/Theme.Sherlock.Light">
<item name="actionBarStyle">#style/actionBarStyle</item>
<item name="android:actionBarStyle">#style/actionBarStyle</item>
</style>
<style name="actionBarStyle" parent="#style/Widget.Sherlock.Light.ActionBar.Solid">
<item name="android:background">#drawable/header_bar</item>
<item name="background">#drawable/header_bar</item>
<item name="android:homeAsUpIndicator">#drawable/up_indicator</item>
<item name="homeAsUpIndicator">#drawable/up_indicator</item>
<item name="android:displayOptions">homeAsUp|showHome</item>
<item name="displayOptions">homeAsUp|showHome</item>
</style>

If I remember correctly, I worked around this issue by moving you should move the android:homeAsUpIndicator and homeAsUpIndicator elements into the main theme declaration. In other words, try:
<style name="AppTheme.ActionBar" parent="#style/Theme.Sherlock.Light">
<item name="actionBarStyle">#style/actionBarStyle</item>
<item name="android:actionBarStyle">#style/actionBarStyle</item>
<item name="android:homeAsUpIndicator">#drawable/up_indicator</item>
<item name="homeAsUpIndicator">#drawable/up_indicator</item>
</style>
<style name="actionBarStyle" parent="#style/Widget.Sherlock.Light.ActionBar.Solid">
<item name="android:background">#drawable/header_bar</item>
<item name="background">#drawable/header_bar</item>
<item name="android:displayOptions">homeAsUp|showHome</item>
<item name="displayOptions">homeAsUp|showHome</item>
</style>
Not sure whether I also had to move up the displayOptions, but you may want to give that a go too in case above doesn't work right away.
By the way, I find naming a style AppTheme.ActionBar and then inheriting from Theme.Sherlock.Light rather confusing. If it were an ActionBar specific style, I would've expected something like Widget.Holo.Light.ActionBar (or any of the other widget styles) as the parent. If it's your main theme, I'd name it accordingly. Up to you of course.
Edit: Updated answer after Jake's comment.

Fully transparent ActionBarSherlock by using theme

I am using ActionBarSherlock 4.0.2.
I need a fully transparent action bar (without the neon color bottom divider). Hence, I have the following style:
<style name="AppTheme" parent="#style/Theme.Sherlock">
<item name="windowActionBarOverlay">true</item>
<item name="icon">#drawable/ic_home</item>
<item name="titleTextStyle">#style/ActionBarCompatTitle</item>
<item name="android:windowFullscreen">true</item>
</style>
By using above code, I will still have the following effect.
In order to disable the background, I put the following code in SherlockFragmentActivity#onCreate. Then the problem gone.
getSupportActionBar().setBackgroundDrawable(null);
However, I would like to see the solution being implemented in styles.xml instead of Java code, as I have many other devices with different screen configuration. I modified the styles.xml to the following, without using the previously mentioned fix in the Java code.
<style name="AppTheme" parent="#style/Theme.Sherlock">
<item name="windowActionBarOverlay">true</item>
<item name="icon">#drawable/ic_home</item>
<item name="titleTextStyle">#style/ActionBarCompatTitle</item>
<item name="android:windowFullscreen">true</item>
<item name="android:background">#drawable/transparent</item>
<item name="background">#drawable/transparent</item>
</style>
However, the neon divider still visible. It seems that my fix using android:background and background does not work. Am I missing something?

<style name="AppTheme" parent="#style/Theme.Sherlock">
<item name="actionBarStyle">#style/AppTheme.ActionBar</item>
<item name="android:actionBarStyle">#style/AppTheme.ActionBar</item>
</style>
<style name="AppTheme.ActionBar" parent="#style/Widget.Sherlock.ActionBar">
<item name="background">#android:color/transparent</item>
<item name="android:background">#android:color/transparent</item>
</style>