James Williams

Implementing Flutter Webs Dad Jokes app in Blocks

After getting the canonical Counter app working with blocks, as well as a tech demo of creating ListViews (pictured below), I set upon remaking Dad Jokes. I made some mistakes, simplified and tweaked some bits and did a semi-real time walkthrough video.

Working with Lists and Web Requests

The first challenge with Dad Jokes was the web layer. The canonical version uses http.dart, dart:convert, and dart:async but I didn't think I wanted to tackle that complexity yet.

Working with a local list provided its own challenges mostly due to my assuming zero-indexed lists. Oops. There is nothing like trying to debug an off by one error compounded by a random function.

Blockly can create lists explicitly by adding each item or by doing a split on a string.

Creating a list with individual elements

Creating a list from a delimited String

On app load, a function is called to select a random joke and add it to the screen.

A function to retrieve a randomjoke from the list of jokes

To simulate the updates that the original app gives you, I used an empty setState on the FloatingActionButton. I didn't create a Center block or any text styles so the text string often overflows and the text is small.

The full representation of theStateful Widget in blocks

Here's from start to finish with a bit of voice-over to explain the tricky bits.

So what's next?

Not really sure. I do have a few possible ideas/questions to ponder. I'm certain that I probably won't try to implement a 1:1 parity version of core Flutter. The “Exit Strategy” section of the Blockly Best Practices stands out to me as a reason to avoid a 1:1 match. Another question is when should you deviate and merge blocks? What limited set of styling could be provided for Text widgets? Could HTTP requests/async be done in a readable and reasonable way?