iOS Dropdown Box

We need a highly simple drop down box coded for our iPhone Application. This work does not require any graphic design. What we want: When you press a button at the top of the screen it drops down a box with 3 buttons inside it, the button that opens the drop down slides down at the bottom of the drop down box, and once press the image of the button changes, and can be pressed to hide the drop down box. Please see attached images for easy explanation. As you can see this is a very simple project, hence we are hoping to get this done quickly and easily. The winning freelancer will be able to do this cheaply and quickly. They should be able to write clean simple code, and comment this. The project will be more likely to be award to freelancers who feel they can code this in a single .m & .h file, and bid low.