Android font family custom font

Android и кастомные шрифты или «Да здравствует API 26»

Как было раньше. Краткий обзор

Если было много view где требовались нестандартные шрифты, то мы использовали что-то вроде такого:

view.xml

CustomFontTextView.class

И это я пропустил огромный кусок который отвечает за то, чтобы не писать каждый раз путь к шрифту, а указывать

Ну, или шли на гитхаб и в результате находили Calligraphy (7000 звезд!)

Ни для кого не секрет что этот подход содержал много минусов как в огромном количестве boilerplate кода, так и в том, чтобы сделать это эффективно и где-нибудь не утечь по памяти запрашивая каждый раз Typeface.

Но все изменилось в API 26

Похоже, гугл наконец-то сдался и решил отказаться от навязывания Roboto и сделал удобное подключение сторонних шрифтов, за что ему огромное спасибо.

Линк для тех, кто любит читать в оригинале.

Теперь подключение состоит всего из нескольких несложных шагов:

1. Создаем папку font в res
Resource type выбираем font

2. Перетаскиваем в новую папку все нужные нам в проекте шрифты

3. Создаем файл для семейства шрифтов.

Обратите внимание: я сразу добавил в пример то как должен выглядеть файл, если вы хотите поддерживать и более старые версии Андроида. (Начиная с 14). Если вам повезло и у вас таргет только на супер-новые девайсы, то ваш файл сократится в 2 раза

Ну а дальше остается только наслаждаться сборкой

Использование в TextView

Используем в стилях

И у вас больше не болит голова об эффективности 🙂

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Using Custom and Downloadable Fonts in Android

At the Google I/O 2017, Android O or simple Android Oreo was launched and it came with a lot of cool features. One of the really interesting features for developers was the new way to apply fonts right in your XML files. Yeah, you heard it right. Now there is no need of writing some piece of code for using the fonts. Also, you can choose from any of the thousands of fonts on Google Fonts and use them in your app.

So, in this blog, you will understand how to use Custom and Downloadable Fonts in Android?

The Older way of using Fonts

Before we move forward to look for the new or the latest way of using the font, let’s revise the older way of using fonts. Before the release of Android O, fonts can be used in the following 2 ways :

• Using Typeface: One would typically need a custom view that extends the equivalent view were trying to apply a font to. In the custom view, one would create a Typeface and then call setTypeface (or a similar method, that, sets the typeface). One would also need to have the font file placed in the assets folder. The code in the custom view typically looks like:

• Calligraphy Library : You can use some existing libraries for various fonts used in Android. One of them is Calligraphy Library.

Using Custom Font in Android

To work with Custom Font, you need to install the latest version of Android Studio 3.x. This is important as some of the features are not supported on Android Studio 2.x — for example, the font resource directory. Once you are done with the installation of the latest version of Android Studio, create a project and add a text view in any of the activity(This is the text view on which we are going to apply custom font). Then follow the below steps :

• Add a font directory to your project: In the Android View, right click on the resfolder and go to New -> Android Resource Directory. Type fontas the name of the font and select fontas the resource type. Then click on Ok.
• Add the downloaded font to the font directory: Copy and Paste your font into res/font.I am using Pacifico font. You can get this font from FontSqirrel.
• Create a font-family XML file: You can create font families which contain a set of font files with their style and weight details. To create a new font family you need to create a new XML font resource. The benefit is that you can access it as a single unit instead of referencing individual font files for each style and weight. To create a font-family, right click on res/fontand choose New -> Font Resource File and give any name. In my case, I am using my_custom_font.xml.

Note: A really important thing to note is that we had to define attributes using both android and app namespaces. The app namespace is what ensures that the feature is backward compatible.

• Set the font in the XML: Now you can use the font-familyattribute to set the font in XML.

Below is the preview of the above code :

Downloadable Fonts

Now that we have seen how custom fonts work, let’s jump onto another novality — downloadable font . Android 8.0 (API level 26) and Android Support Library 26 introduce support for APIs to request fonts from a provider application instead of bundling files into APK or letting the APK download fonts. A font provider application retrieves fonts and caches them locally so that other apps can request and share fonts. How cool is that!

The feature is available on devices running Android API version 14 and higher through the Support Library 26.

Picture courtesy : Android Developer website

As you can see in the image above, apps using Downloadable Fonts make a FontRequest using the FontsContract API which retrieves the Typeface from the Font Provider. The Font Provider does not need to download fonts if it already exists in the Font Cache.

Benefits of downloadable fonts :

• Reduces the APK size
• Increase the app installation success rate
• Improves the overall system health as multiple APKs can share the same font through a provider. This saves users cellular data, phone memory, and disk space. In this model, the font is fetched over the network when needed.

In order to use the downloadable font in android studio, follow the below steps :

• If you want to use Android Studio to generate the required files, then you’ll need version 3.0+. Add the following (version 26+) to your module’s build.gradle:

• Select a text view in your app that you want to apply the font to and click on the fontFamily attribute under Attributes in the graphical layout

Select the “More Fonts…” at the bottom, which will open the dialog below.

• Make sure to have “ Create downloadable font” selected. This results in three files being downloaded — lato.xml, font_certs.xml and preloaded_fonts.xml.

This file contains the font attributes for loading a Typeface from the Google Fonts Provider Application.

The system uses these certificates to verify the font provider’s identity, to avoid getting fonts from an unknown source. If using the steps above, Android Studio should have automatically generated the string certificates for dev and prod in font_certs.xml below.

preloaded-fonts.xml
This file is referenced in the Android manifest which helps the framework pre-load fonts to avoid delays when the app is launched.

• Make sure this line is added to your app’s Manifest file, Android Studio should have done this automatically:

• Great, now you are ready to apply the fonts in XML!

All I had to do was set the font family in the app’s theme to get TextViews throughout the app to change to Lato, including parts that were bold or italicized. However, if you want to configure the weights, you can follow the same steps to get Lato Bold using Android Studio, and change the weight manually in lato_bold.xml that you can then apply in XML layouts:

That’s all about the custom and downloadable fonts in android. Hope you like the blog.

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Custom Fonts on Android with Android Support Library

Android Oreo was officially unveiled a couple of weeks ago, and it introduces a lot of new and exciting features. If you haven’t already, you should check the developers website for the list of what’s new in Android O.

One of the really interesting features for developers is the new way to apply fonts right there in your XML files.

That’s great right? Yup. Except that it works out of the box for only API 26 (Android O).

In this post, we will look at how to backport this awesome feature to older versions — down to API 14 using the Support Library 26.

Custom Fonts on Android — Old Ways.

Previously on Android, there were limited ways to use custom fonts on Android. The following techniques are the ones I consider the most popular ways of implementing custom fonts in Android:

1. Custom Views

One would typically need a custom view that extends the equivalent view where trying to apply a font to. In the custom view, one would create a Typeface and then call setTypeface (or a similar method, that, sets the typeface). One would also need to have the font file placed in the assets folder.

The code in the custom view typically looks like:

2. Calligraphy Library

Thanks to some awesome developers, there is another approach to having custom fonts in your apps — and the library is called Calligraphy — https://github.com/chrisjenx/Calligraphy. The usage is fairly straightforward, and the pitfalls are clearly identified. But as with every library, it comes with the penalty of adding extra dependencies thereby increasing method count.

Custom Fonts with Support Library — The New Way.

Thanks to the good folk at Google and their work on Android Support Library 26 it is now possible to declare fonts in XML — something called font families, and also programmatically without the need of an extra library besides the support library (which you most likely already use in your app anyway).

How to

In order to implement this feature using the support library, there are a number of short and precise steps one has to go through.

i. Add the fonts to the fonts resource directory

Just like string and drawable resources, the fonts are now available as resources. First step in making this happen is to add the font files to the res/font folder in your project. This ensures that they are packaged as resources, and are easily accessible in a similar way we access other types of resources: @font/niceFont in XML or as R.font.niceFont in code.

ii. Create a font family

Font family is something that was introduced in Android, and it is used to define a group of fonts and their corresponding style. So the system can determine what font resource to use for regular, bold and italic styles and weight configurations. A typical font family looks like this:

A really important thing to note is that we had to define attributes using both android and app namespaces. The app namespace is what ensures that the feature is backward compatible.

iii. Using the fonts

Now that we have defined the fonts, we could either use it programmatically, directly in XML layouts, or via a style that will be applied to the view in the layout.

Let’s have a look at how we could use the custom fonts in each case.

a. Using the font programmatically

We can decide to use this font programmatically in a way quite similar to how we have always been doing, except that we’re not creating this Typeface from an “asset”. Rather, we’ll be getting it as a resource. Doing this programmatically (for backward compatibility) will look like:

b. Using the font-family directly in the layout file

You can apply this font family created in step ii above directly in the layout file. Using it will look something like this:

Something worth noting here is that it appears that one can specify the fontFamily attribute using either the android or app namespace.

The catch here is that the android:fontFamily attribute is not available for API levels below API 16, while we’re trying to backport this feature all the way to API 14.

To go around this, gotcha, we can use the app namespace instead. However, there seems to be another interesting discovery: Android Studio flags the app:fontFamily attribute as “Unexpected namespace prefix app found for tag TextView” as seen in the screenshot below, but it seems to work for me regardless of what AS is saying. (Dear reader, I’d love to get your feedback if you’re able to reproduce this weird behaviour too).

c. Using the font-family via a style

Another usage of the font family is via a style (or text appearance). We could specify the fontFamily attribute to use the font family created in step ii, and then in turn use that as a text appearance or even style in the layout. Defining this in the styles.xml file will look something like:

We can now use this TextAppearance style as a text appearance on our textviews accross the app. The usages will look something like:

It’s interesting to note that the system is able to pick the appropriate font defined in the @font/app_font font family resource file that best fits the textStyle given to the view.

Resources and further reading

Summary

In summary, in this post, we have looked at how to implement backward compatible custom fonts in Android using the Support library 26.

Want actual code? I have written a sample code that demonstrates everything approach discussed in this post. Feel free to check it out at https://github.com/segunfamisa/android-fonts-xml-sample.

Another font-related improvement in Android O worth looking at, in my opinion is the downloadable fonts. This is really cool because it means you won’t have to bundle the font files with the app. Instead, you will specify which font provider (like Google Fonts) you want to retrieve them from, and apply the typeface on the desired view. Check the resources and further reading section for a direct link to the official docs.

Thank you so much for reading this post, please feel free to share if you found it helpful. Also, please feel free to make corrections, suggestions and ask questions in the comment section at the bottom of the page.

Thanks to Efe, Michael and Moyin for reviewing this post. :tada:

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