Why would you use apply in Kotlin?

Here is an answer to the Kotlin interview question "Why would you use apply in Kotlin?":

The apply function in Kotlin is a scope function that allows you to perform a series of operations on an object and then return the object itself. It is particularly useful in the following scenarios:

Initializing Objects

When creating an object, you often need to set multiple properties. Using apply allows you to set these properties in a more concise and readable way:

val person = Person("John Doe", 30).apply {
    address = "123 Main St"
    phoneNumber = "555-1234"
}

Chaining Method Calls

When working with builder patterns or fluent interfaces, apply can help you chain method calls together:

val button = Button(context).apply {
    text = "Click me"
    setOnClickListener { /* handle click */ }
    layoutParams = ViewGroup.LayoutParams(
        ViewGroup.LayoutParams.WRAP...