19 January 2015, 03:03
In my home office I attach an external keyboard and monitor to my MacBook Pro. Sacha cat likes laptop keyboards, and frequently sits on it, accidentally pressing keys and moving the mouse by rubbing his furry bottom against the trackpad.
Here’s a solution to this quandary that’ll let you tap the Option key (Alt on some keyboards) five times to disable the MacBook keyboard and trackpad, but leave the external keyboard and mouse working. The instructions below are for OS X Yosemite.
- Open System Preferences, then click the Accessibility icon.
- Click the Mouse & Trackpad icon in the list at the left.
- At the top right, click the Options button alongside the Enable Mouse Keys checkbox.
- Put a check in Ignore Built-In Trackpad When Mouse Keys is On, and click OK.
- Close System Preferences, then in future when the MacBook keyboard is sat upon by a cat, tap Option (Alt) five times. When the cat has moved on, tap Option five times again to restore everything to normal.
I’m still testing this but it seems to work pretty well. There are two perhaps major drawbacks:
1. This doesn’t deactivate all the keyboard. It just deactivates most keys. Tapping 7, 8, 9, U, I J, K or L will move the mouse. Tapping the letter “I” will cause a mouse click (see this diagram on Apple’s website). If the cat rests their furry paws against any of these keys, just try lifting and reseating him/her.
2. The numeric keypad (if your external keyboard has one) will no longer type numbers but will instead control the mouse. In my opinion this is a price worth paying.
Pro tip: If you put a tick alongside Show Accessibility Status In Menu Bar in System Preferences, you’ll get a visual confirmation whenever you turn on/off this feature, and can click the icon to see if it’s turned on.
UPDATE: Hmm… The Cmd/Option/Shift keys remain active using the above method, and Sacha cat still presses them when sitting on the keyboard — causing havoc for me while I’m trying to work. Luckily a guy on Reddit points out that the free-of-charge Karabiner includes an option to automatically deactivate the internal keyboard when an external keyboard is connected (within Karabiner click the Change Key heading, then look under the General category). Together with using the method discussed above to deactivate the trackpad, this seems to offer the best all-around cat vs. keyboard protection.