We've already seen how Kotlin can use the object keyword to create an anonymous instance of a class. This can be used when we want to pass some functionality as an argument to another method. But if the interface or a class you are creating has only one function, then using anonymous classes may feel cumbersome and too verbose.
This is where lambda expressions, or lambdas for short, come into play. Lambdas can be best described as short pieces of code that can be passed to other functions. If you have a Java background, then you probably remember how Java 8 was highly anticipated because it finally brought support for lambdas.
In UI programming, event listeners are the perfect use case for lambdas. We're going to take a look at an example from Android. Android still uses Java 6, and there we can't use Java lambdas, so it will be perfect to show how using Kotlin instead of Java is less verbose if you can't use the latest Java versions. On android with Java, you would set a click listener...