Tippy computes the tip and total amount for a bill. The app uses the base amount and tip percentage to calculate the amount owed, and it also describes the quality of service based on the tip.

Time spent: 18 hours spent in total

The following required functionality is completed:

• User can enter in a bill amount (total amount to tip on)
• User can enter a tip percentage (what % the user wants to tip).
• The tip and total amount are updated immediately when any of the inputs changes.
• The user sees a label or color update based on the tip amount.

The following extensions are implemented:

• A second screen allows the user to see their payment history.
  • Two buttons on the main screen let the user save the current payment and view the past history.
• The total amount can be rounded up to the nearest dollar.
  • Doing so will recompute the tip amount and tip percentage based on the rounded total.
  • Tapping the round switch again will restore the total based on the original tip percentage.
  • Editing the base amount or tip percentage manually will reset the round switch to the default.
• Users have the ability to split the bill among 1-15 people.
  • Changing the split updates the Per Person cost immediately.
• The base view starts at $0.00 and updates with user input, keeping the currency formatting. E.g. $0.00 -> $0.09 -> $0.95 -> $9.53.
  • The default values for base, tip, total, and per person are $0.00.
• The keyboard hides when the user interacts with the progress bars.
• The app has a custom color scheme.

Here's a walkthrough of implemented user stories:

The main challenges when building this app occurred when implementing the second activity, or screen, that allows users to view their payment history. I spent time conceptualizing how I would build, store, and update my data structure to store payment objects. After I had created the data strucutre, I had to figure out how to pass the information from the main screen to the history screen. This exercise was a great opportunity for me to learn about intents, which communicate between multiple activities and allow data to be transferred from one activity to another.

Furthermore, I implemented a RecyclerView to display the list of payments, which presented its own set of challenges. In doing so, I created an adapter for the recycler as well as a separate .xml file to format a single view element within the list.

With more time, I would implement persistence so that information could be stored indefinitely. A simple solution would be to use a local file whereas more involved solutions would use either a local SQLite or a remote Firebase database. I would also have a better indication of when a payment was saved either by inactivating the button and changing its color, or displaying a popup window. Lastly, I could also implement a reset button to set the inputs back to their default values.

Copyright 2020 Dean Stratakos

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    http:https://www.apache.org/licenses/LICENSE-2.0

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