mac系统里关闭字符重音提示开启重复按键

You can try the following on Yosemite in the Terminal. Works in Mavericks, but may not in Yosemite.

defaults find ApplePressAndHoldEnabled

If it returns 0 or not found, then:

Quit the application in which you were unable to use the long keypress.
defaults write -g ApplePressAndHoldEnabled -bool true
killall Finder

If the prolonged keyboard press still does not produce results, then in System Preferences > Keyboard > Input Sources, add a Spanish Keyboard, and then reboot. Try the long keypress again, and hopefully, you now have the pop-up accents.