This course is rarely offered at Miami University, so I immediately signed up for it when they delivered it in the Summer of 2021. The class dove straight into topics as it was only six weeks long. We had five projects, a final project, ‘exam-like weekly quizzes, and assignments accompanying our lecture videos. The class was delightful.
I created this program as my final project for this class. I was between a couple of ideas since we got the freedom to choose, but I decided to use a meal tracker. I picked this idea solely because I wanted to experiment with APIs. I thought the concept of a meal tracker gave me a lot of opportunities to find different APIs about food online. So I paid to use two separate APIs from the same website, called spoonacular. I used one to search up menu items, and based on the results of the other API, I would get the nutrition facts using another API. The program taught me a lot about this side of computer science. Along with the APIs, there were other features within the application. Additional project requirements included web services, user preferences, MVVM architecture, local databases, multipage, listviews, and images. The program was 22% of my final grade. I got a 94% on it, deducting some points from the midpoint demonstration.
If you download this and run this program in Visual Studio, you might have to do a couple of things to run for the android and UWP simulation. First, you must download the workload using Xamarin for cross-platform mobile application development. You can do this by going to
Tools > Get Tools and Features > Download Mobile Development with .NET
This should allow you to run it within UWP and potentially an android simulation. If you are still having problems with running the android simulation, check out this article and it will most likely fix the problem. However, if it doesn’t fix it, you can honestly email me, and I can help you out and most likely update this document with more solutions.
APIs Used:
The best part about this program, without a doubt. I found this elegant API to use online revolving around food. The two that I used depended on one another within my application. You couldn’t query the second API without the results from the first API. Testing was a bit more tedious and challenging, but it worked out great. The first API takes a series of food/meal keywords and lists the results closest to the keywords. So if I searched “Taco Bell,” it would return the top ten menu items from Taco Bell.
Since this API only gave us the menu item, image, name, and restaurant, I had to take the food ID and query a second API and query that used the food from the first. It’s a bit meta and complicated at the start but very elegant when you draw it out on paper! The second API would bring back all the nutrition facts the GUI will show. After this, we have all the information needed to add to our local database/the user’s food diary.
After this, we have all the information needed to add the entry to our local database/the user’s food diary. As you can see, the user can choose what meal they want to add it to and the date. That would get transferred to the Diary page and updated as needed.
Spoonacular API Dashboard:
User preferences are a simple way to store values locally on a user’s device. It’s not for significant data for the application, just more minor stuff. For the sake of my project, I have the calorie goal for the user set as a preference. If you delete the application from the device, redownloading it would reset the preference.
View ↔ Controller ↔ Model
A complex concept to learn within mobile applications. You have three different components within this concept that talk to each other. First, our application uses a slider on the summary page to update the calories on the screen. Second, instead of making an on-update function, which we could have quickly done, the slider is tied directly to everything that needs to be updated on-screen. Third, it makes the phone use less power since it is more efficient and streamlined.
I used Visual Studio’s NuGet package search feature for this application to find the SQLite-net-PCL package. This package simulates any ordinary database that you would see in an application. However, unlike preferences, this is where we can store more significant amounts of data within our application. We used this application to keep the food entities in a giant schema that the application referenced when loading the Diary page. The package saved all of the data locally to the device. The table below is a great visual of the schema within the application.
| id | Date | Meal | Name | Calories | Fat | Protein | Carbs |
|---|---|---|---|---|---|---|---|
| PRIMARY KEY int | DateTime | string | string | double | double | double | double |
A multipage application UI defines your application’s navigation between multiple pages. My application is tabbed. You can navigate between pages using the buttons at the top or bottom of your screen. The example below demonstrates only two tabs, Diary and Track.
Another navigation feature used is stacked navigation. Furthermore, a page will push on top of the stack when searching for a meal. You cannot return to the original tabbed navigation until the user pops all the pages within the stack navigation.
List views appear throughout the program and show the diary contents, including the macronutrients and the food name. Also, the search results list view creates a set of buttons where the user can get the additional macros for the food.
...🥁now let's put all of the slices🍰 together...drumroll please🥁...
