Going from scratch to a full-blown Flutter app in two days

Set up Firebase for my project and configure the Android version of the app with it.

If that sounds new to you, check here.

For the choice of a database, I went with the new Firestore which, for those of you who expected Realtime DB, is Realtime DB but better.

I also enabled Firebase Authentication to allow Google sign-in.

After that was done, I jumped to the code.

I created a new Dart file and added methods for signing in with Google.

Then, I quickly moved to implement a very basic login page where I created an authentication listener to look for any login events.

If the user was logged in successfully, I sent them straight to my home page along with the user id of the user.

I implemented a cloud function to automatically index all my clients in an ascending order of user Id.

I used a Firestore instance created through the user id that was passed from the login screen, in every file that required use of database variables.

An example:Here, answers is the name of my collection and each individual document inside it corresponds to a user.

To build the UI using variables from Firestore, I made use of StreamBuilder; It is a proven way to build dynamic UIs based on values from a stream but this is where I ran into my first major roadblock in this project.

While running the Tasks screen, I encountered “method called on null” exceptions repeatedly.

On careful debugging, I figured out that only the variables that had changed in the database were being sent in the DocumentSnapshot that I was relying on to build my UI.

As a consequence, the logical checks on the other variables started throwing exceptions.

To remedy this, I created a Map to store the status of variables in the current DocumentSnapshot and only those variables would be checked for which the value corresponding to their key returned true.

The next obstacle, however, would leave me scratching my head for six full hours; yes.

On running the code for the Android version, I ran into the following formidable gradle error, for which I could find no fix anywhere on the internet.

Every hack that the Stack Overflow gurus suggested was obliterated by this one exception.

Launching lib/main.

dart on Android SDK built for x86 in debug mode… Initializing gradle…Resolving dependencies… Running Gradle task ‘assembleDebug’… FAILURE: Build failed with an exception.

* What went wrong: Could not determine the dependencies of task ‘:firebase_core:compileDebugAidl’.

> Could not resolve all task dependencies for configuration ‘:firebase_core:debugCompileClasspath’.

> Could not find com.



Required by: project :firebase_coreI had almost lost all my patience but I refrained from giving up because I had full faith in my idea and above all, limitless desire to not let this opportunity go waste.

I had a chance to be the real developer I always strived to be and here was my challenge.

I sat back and went through Android documentation looking for possible causes of failure.

One page talked specifically about how AndroidX had compatibility issues with Flutter.

“Aha!” I recalled that I had upgraded to AndroidX last year and that is where the fire was.

I reduced the dependencies' versions to pre-AndroidX levels and (loud cheer) my app successfully launched!.At the end of this slugfest, I had lost eight hours to unproductive work and had almost every other screen left, to implement.

I took up the Questions page next.

First, I visualize what the page should look like; things to keep in mind: it should be easily answerable (implies, no text fields) and it should cheer the user up (colors, a lot of color).

Second, I look for plugins that will speed up my work of implementing a slider for answering questions.

Luckily, I found one pretty fast.

I designed the UI very rapidly; added the slider, configured the colors (I implemented a gradient that synced well with the slider value).

Question UIIt was not until late Saturday night, when I checked my Nokia that I found I would have one more day to bring my house in order because the deadline had been extended.

Nevertheless, I made it a personal goal to have the app working by the end of Sunday.

SundayWith the cloud integration working, I moved to implement my Dashboard which took values from the cloud, ran a check and displayed insights to the user.

Building the UI had, by then, become a cake-walk.

I implemented features for the rest of the pages as well.

DashboardWhen put to test, however, the code threw up another exception, this time about a “failure in performing transaction; operation timed out”.

The method responsible for the exceptionI spent a significant amount of time trying to rectify this issue, to no avail.

At this point, I had a Plan B which was to scrap all cloud integrations and make a “stateless” app just to demonstrate basic UI features.

Of course, that was something I wanted to avoid as it would take away all life from this app.

Close to midnight, I had given up on the cloud and was working on my Plan B when out of nowhere, I conceived the idea of an SQL Database.

SQLite VersionI researched on Flutter and SQL integration and within a couple hours, I had a roadmap for the new incarnation of my app.

I wrote down a Database class, added methods for adding, updating and deleting clients.

I also hastily assembled a Model class that represented a single client.

By that time, I knew sleep wasn’t an option and was very definitely missing my Monday class ????‍♂️.

I replaced my code with SQL integrations and tested basic features to make sure I was going in the right direction.

By five A.


I had an SQLite powered app ready which only required polishing, images and other visual touches.

Final DayI looked for crisp infographics to drive the visual appeal for my app and even after I landed good images for the app, it was a pain to actually make them load.

The problem?.YAML’s indentation rules ????‍♂️.

As the day progressed, I tightened some screws, plugged some leaks and made the app ready for showtime.

I went out and shot the pitch (which you have seen by now) in a single take and tried to put as much information as my drowsy self possibly could.

I then put together a PowerPoint presentation explaining the app’s idea and implementation and finally I made the submission well before scheduled time.

This hackathon has been an exhilarating experience.

It brought out the best in me and pushed me to the very limits of my productivity.

Every exception was a challenge that I had to fight independently and with the full valour of my soul.

In the end, I felt a sense of satisfaction and fulfillment that I had been craving for quite a long time then.

Here is the repository for the SQLite version of the app and here, you will find the cloud version.

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