If you are writing an app, that uses a string containing numbers, for example:
Deleted 1 message
Deleted 2 messages
You could manually create two different strings, and show either one by using an if/else, depending on the number variable.
However, as you start internationalizing your app, by adding more translations, this quickly gets out of hand!
Using Plurals
Luckily, theres a great solution for this. In Android, you can use something called "plurals".
You can use plurals in their own resource file, or just add them to the strings.xml file. I like to have them in my strings.xml file, so I can keep track of all strings in one place, and easily translate them to other locales.
So, in strings.xml, add a plurals element, like below:
You can then add the same element to your other strings.xml files, to get them translated.
To use the plural string in your app, you get it like this:
Depending on the deletedItemCount variable, you will now get a formatted string, with the correct pluralization.
There are several different values for quantity, for more information, and tips check out the documentation.