Android Development with Kotlin

Inline properties

Since Kotlin 1.1, the inline modifier can be used on properties that do not have a backing field. It can be either applied to separate accessors, which will result in their body replacing usage, or it can be used for a whole property, which will have the same result as making both accessors inline. Let's make an inline property that will be used to check and change an element's visibility. Here is an implementation where both accessors are inline:

var viewIsVisible: Boolean 
inline get() = findViewById(R.id.view).visibility == View.VISIBLE 
inline set(value) { 
  findViewById(R.id.view).visibility = if (value) View.VISIBLE   else View.GONE 
} 

We can achieve the same result if we annotate the whole property as inline:

inline var ...