Tip Calculator is a tip calculator application for iOS.
Submitted by: Maria Notohusodo
Time spent: 12 hours spent in total
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)
- 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:
- Splitting bill to determine each person amount to pay.
- Settings page to save the default tax percentage.
- Settings page to select & save the color theme.
Here's a walkthrough of implemented user stories:
GIF created with LiceCap.
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: The app is very simple. Outlet is used to programatically control/change the view (text, color, etc). Action is used as an event to trigger the code to do certain task.
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: Strong reference cycle can be created when 2 class instance properties hold a strong reference to each other. A closure is like a class, a reference type. A strong reference cycle is created when a closure is assigned to a class instance property and the closure accesses a property/method of that instance.
Copyright [2017] Maria Notohusodo
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
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distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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