I have a MacBook Pro with the current software. I just purchased AppleTV. I can show my iPad and iPhone on the screne - mirroring, but ther is no icon at the top of my MacBook to turn this on. What am I doing wrong?
Check the mirroring option in system preferences > displays is turned on, if there is no option your Mac doesn't support mirroring.
AirPlay Mirroring requires a second-generation Apple TV or later, OS X 10.8 or better and is supported on the following Mac models: iMac (Mid 2011 or newer), Mac mini (Mid 2011 or newer), MacBook Air (Mid 2011 or newer), and MacBook Pro (Early 2011 or newer). It also requires the computer to be using wi-fi.