A font file either a. TTF or a. OTF file is added to a Xamarin. Android application just like any other resource, by copying files to a subdirectory in the Resources folder of a Xamarin. Android project. Fonts resources are kept in a font sub-directory of the Resources folder of the project. The build action should be automatically set by the IDE. When there are many similar font files for example, the same font with different weights or styles it is possible to group them into a font family.
A font family is a set of fonts that have different weights and styles. For example, there might be separate font files for bold or italic fonts.
Each font family should have it's own XML file. Then create a new XML file in the font folder for the font family. The name of the XML file has no affinity or relationship to the fonts being referenced; the resource file can be any legal Android resource file name. This XML file will have a root font-family element that contains one or more font elements. Each font element declares the attributes of a font. The following XML is an example of a font family for the Sources Sans Pro font that defines many different font weights.
The fontWeight attribute corresponds to the CSS font-weight attribute and refers to the thickness of the font. This is a value in the range of - The following list describes the common font weight values and their name:.
Once a font family has been defined, it can be used declaratively by setting the fontFamily , textStyle , and fontWeight attributes in the layout file. Interact with peripherals. Build user-space drivers. Manage devices. Create a build. Push an update. Chrome OS devices. App architecture. Architecture Components. UI layer libraries. View binding. Data binding library. Lifecycle-aware components. Paging Library. Paging 2.
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User interface. Add motion to your layout with MotionLayout. MotionLayout XML reference. Improving layout performance. Custom view components. Look and feel. Splash screens. Add the app bar. Control the system UI visibility. Supporting swipe-to-refresh.
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Sharing files with NFC. This enables Android to verify the identity of the font provider. You have to do this for font providers that are not pre-installed on the device or when using support library. You define font provider certificates in a string-array.
If the font provider has more than one set of certificates, then you must define an array of string arrays. The Google font provider used with the support library uses two sets of certificates, and the next step is to define an array for each set.
The FontQuiz application is still missing one key feature — text in quiz questions always must be in font from the question. You can implement requests to fetch downloadable fonts and apply them to a View in code as well. You must use the FontsContractCompat class from the support library to support Android versions older than 8. Your task will be to use it to request and set a random font on the quiz question Activity.
The logic to pick a random font for the question and four offered answers is already there. Your job is to request and show the font with the name passed to showFont. First, hide all the buttons and show a ProgressView that will show hat font is loading by adding:.
To request a new font use requestFont method from FontsContractCompat. Add following to the end of showFont :. Requesting a downloadable font is an asynchronous operation. Method requestFont passes the result through a FontsContractCompat. FontRequestCallback interface. Use the Typeface instance passed to set the font on a View. Enable all the buttons and hide progress indicator:. Use it to display an error message by calling showError and passing it error code:.
FontContractorCompat uses it to execute retrieving a font on a Thread associated with that Handler. Make sure you provide a Handler that is not associated with a UI thread. For convenience, create a private field that will hold the handler and a property that will initialize and retrieve it:.
Using the handlerThreadHandler property will initialize the handler on the first use and return it. After you answer a question on the quiz, it would be cool to display a simple fact about the font in question.
So your next task will be to retrieve information about a font family. To get information about available fonts use fetchFonts from FontsContractCompat. Like in the previous task, create a FontRequest first:. Get it on GitHub: Java Kotlin. The sample plays a video. The video keeps on playing when the app is turned into Picture-in-Picture mode. On Picture-in-Picture screen, the app shows an action item to pause or resume the video.
DownloadableFonts - This sample demonstrates how to use the Downloadable Fonts feature introduced in Android 8.
Downloadable Fonts allows apps to request a certain font from a provider, instead of bundling it or downloading it themselves.
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