Please review code

[jvlin]

@timothy1ee @nesquena

I was wondering if you can tell me how to put the convert button on the keyboard instead of on the screen. Also I wasn't sure which one took precedence when there are values in both F and C text fields.

Is IBAction preferred over using target and action selector to handle button click event handling?

[timothy1ee]

Looks good! Read this for customizing the keyboard: http://blog.carbonfive.com/2012/03/12/customizing-the-ios-keyboard/

IBAction is equivalent to target and selector, neither are preferred.

• The mockup was deliberately ambiguous about how to handle whether to convert from Celsius to Fahrenheit or vice versa. One good option was to track which textfield was the most recently edited. Your choice was a bit suboptimal because once both textfield have values, you always convert from Fahrenheit to Celsius.
• There are two ways to register for events for a UITextField: set the delegate or use the generic control events in Interface Builder. Generally speaking, it's more common to use the UITextField delegate methods.
• Optionally, you could have enforced input validation for the temperatures.
• The best keyboard to use is the decimal keyboard. The only downside is there is no negative key.

[jvlin]

I wanted to detected the last changed textfield but wasn't sure how to do it. Can you please elaborate on what you mean by setting delegates? Do I use this technique to determine which one was edited most recently?

[timothy1ee]

When an UITextField is being edited, the isEditing property is YES. Or, when the user begins editing in a textfield, you can store the active textfield in a property like activeTextField.

Many UI elements like UITextField, UITableView, UIAlertView have events associated with them. For example, a user has begun editing, finished editing, changed text, etc.

See this video for an example of how to set and use the UITextField delegate: http://www.youtube.com/watch?v=c5SRKfGiHSg

[jvlin]

Thanks, I've added and committed delegate codes to convert the last edited field and to convert when return button is pressed.

[timothy1ee]

Great, looks good.