Pre-work - iTip
iTip is a tip calculator application for iOS.
Submitted by: Antonio Alves
Time spent: 6 hours spent in total
User Stories
The following required functionality is complete:
- User can enter a bill amount, choose a tip percentage, and see the tip and total values.
- Settings page to change the default tip percentage.
The following optional features are implemented:
- UI animations
- Remembering the bill amount across app restarts (if <10mins)
- Add a light/dark color theme to the settings view. In viewWillAppear, update views with the correct theme colors
- Using locale-specific currency and currency thousands separators
- Making sure the keyboard is always visible and the bill amount is always the first responder. This way the user doesn't have to tap anywhere to use this app. Just launch the app and start typing
The following additional features are implemented:
- 3D Touch shortcut to copy the last tip total
Video Walkthrough
Here's a walkthrough of implemented user stories:
GIF created with LiceCap.
Project Analysis
As part of your pre-work submission, please reflect on the app and answer the following questions below:
Question 1: "What are your reactions to the iOS app development platform so far? How would you describe outlets and actions to another developer? Bonus: any idea how they are being implemented under the hood? (It might give you some ideas if you right-click on the Storyboard and click Open As->Source Code")
Answer: It's pretty simple to start doing something cool, although your code can get messy really fast and using IBOutlets and IBActions looks strange at first to where you should add them, to a ViewController or a View only, it works basically with XML, where there's tags that represent actions and outlets properties that contains destination code and id;
Question 2: "Swift uses Automatic Reference Counting (ARC), which is not a garbage collector, to manage memory. Can you explain how you can get a strong reference cycle for closures? (There's a section explaining this concept in the link, how would you summarize as simply as possible?)"
Answer: You can end up with a reference cycle if you capture a strong reference for another class that already has a strong reference to the class where you referencing it from inside a closure without using a weak or unowned to break the strong reference.
License
Copyright [yyyy] [name of copyright owner]
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.