Xamarin.Android - android:fontFamily doesn't work

Question

I need to change textView font using android:fontFamily. The problem is that it gives me errors and I have no idea why

My code:

Answer 1

Support from only API-26 and above:

• Add your font files in the Resources/font directory

• For API-26+ only support using android:fontFamily is fine:

  android:fontFamily="@font/tastysushi"

But... for API 16 through 28+, you need to setup/use the Android Support library

Support from API-16+

• Add the Xamarin.Android.Support.Compat package (v26 or higher)

• Add the Xamarin.Android.Support.v7.AppCompat package (v26+) if you are using fontFamily in your AXML layouts (otherwise you can programmatically assign the font family and use Activity subclasses)

• Your activity must be a subclass of AppCompatActivity in order for the layout/AXML-based app:fontFamily attribute to work

• Add the font files in the Resources/font directory

   |-Resources
   |  |-font
   |  |  |-tastysushi.ttf
  

• Optional, but handy, create a font family xml file in Resources/font directory (both android and app namespaces must be defined)

  <!-- Resource/font/sushi.xml -->    
  <?xml version="1.0" encoding="UTF-8" ?>
  <font-family 
  xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:app="http://schemas.android.com/apk/res-auto">
  <font
      android:fontStyle="normal"
      android:fontWeight="400"
      android:font="@font/tastysushi"
  
      app:fontStyle="normal"
      app:fontWeight="400"
      app:font="@font/tastysushi"
  />
  

  Note: You can add bold and italic font elements also to the font family... and assign each one a different font file from the same family of fonts...

• In top element of your layout file add the app: namespace:

  xmlns:app="http://schemas.android.com/apk/res-auto"

• Now the fontFamily attribute must use to use the app: namespace

  app:fontFamily="@font/sushi"

Note: The @font/ can either reference the actual font file or the xml-based font family file

Note: You can also embed the fonts in styles so you do not have to populate each AXML element with the font family...