it keeps popping up all the time
Try this: Go to Settings > Apps > swipe to All tab > look for Google App then uninstall updates. Restart your phone and check Google Play store for updates.
I don't know the answer but I have the same problem
I keep reseting my phone to factory settings to get the keyboard to come up again when this problem happens
but its getting annoying. Thinking about tossing the phone in the trash soon...