Month: April 2017

Figure out from the documentation how to use the iOS struct NumberFormatter to format your display so that it only shows 6 digits after the decimal point (instead of showing all digits that can be represented in a Double). This will eliminate (or at least reduce) the need for Autoshrink in your display. While you’re at it, make it so that numbers that are integers don’t have an unnecessary “.0” attached to them (e.g. show “4” rather than “4.0” as the result of the square root of sixteen). You can do all this for your description in the CalculatorBrain as well.

First of all, the last task had a tiny bug. when entering e.g. “0,” will show a leading zero:

    @IBAction func backSpace(_ sender: UIButton) {
            ...
            if text.isEmpty || "0" == text {
                ...
    }

Continue reading “cs193p – Assignment #1 Extra Task #2”

Implement a “backspace” button for the user to touch if they hit the wrong digit button. This is not intended to be “undo,” so if the user hits the wrong operation button, he or she is out of luck! It is up to you to decide how to handle the case where the user backspaces away the entire number they are in the middle of typing. You will probably find the Strings and Characters section of the Swift Reference Guide to be helpful here.

Add the backspace button to the storyboard:

Continue reading “cs193p – Assignment #1 Extra Task #1”