This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
setText() wants a String as an argument, so you need to convert your float to a String. There are (as is often the case) several ways to do this, but easy one is the static method String.valueOf(); there's an overloaded version of this for just about every primitive type. So you could say