AudioKit is a really excellent package for developing audio applications for iOS and some related environments. It is comprehensive enough to be overwhelming at times. Sometimes it helps to break it down into modular classes, which you can then use in your view models or whatever architecture you might be using for Swift or SwiftUI. I won’t describe installing AudioKit here, since that is covered well elsewhere.

Here are some simple classes that I made for using an oscillator, playing back a sample and recognizing a pitch. You might want to parameterize them further for your own purposes.

I also…

I like this article a lot, but when I tried to build from the repository, it said that it needed screen_size_builder.dart. That file had been deleted from the repository for some reason. When I added it back, I was able to run the code.

I really like this article. It seems to get around some of the two-pass problems of doing this by some other methods, at least in my own case.

I originally just tried to cut-and-paste the code and use it as a "wrapper" widget, but because of "Contents()" and some other things, that didn't quite work. Also, I thought the default color could be a problem. Using 600, 600 as a default value, this is what worked for me:

class ScalingBox extends StatelessWidget {

const ScalingBox({

Key key,


this.logicWidth = 600.0,

this.logicHeight = 600.0,

}):super(key: key);

final Widget child;

final double logicWidth;

final double logicHeight;


Widget build(BuildContext context) {

return SizedBox.expand(

child: Container(

child: FittedBox(

fit: BoxFit.contain,


child: SizedBox(

width: logicWidth,

height: logicHeight,

child: child,







Very nice and just what I was looking for today. I have some applications that use MIDI, audio and music notation on iOS and Android. I want to convert some of the code to Flutter.

It was so nice of you to include the source. It ran on my Android LG v40 phone right away. I had to do a small thing to get it to run on my iPhone XS Max. Quite possibly it is because I'm using Fluter 2. I've seen similar on other projects. It was easy to fix, though. I just needed to delete the Podfile and let Flutter rebuild things.

I couldn't find File>Project Structure>Authentication . I realize that a lot of these things change frequently.

Your tip to uninstall and reinstall homebrew if there was a problem installing fastlane was a really good one! I think it could have saved me trouble in other situations. It was really handy to have your ruby script lines in the article!

I have found Mac to be more touchy about these sort of issues since Catalina. It was also good to know that you were having success using homebrew. Thanks, Bruce

Bruce Cichowlas

iOS/Android contract developer. I am also creator of Play Along Keys, a free music performance app in iOS and Android stores. You don't need music experience.

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