Xamarin Objective Sharpie: a binding definition generator for third party Objective C libraries

Xamarin iOS allows you to consume a third-party Objective-C library. Before you had to use Xamarin.iOS's Binding Projects to create a C# binding to the native Objective-C libraries. Inside this Binding project you’ll find two files: ApiDefinition.cs and StructsAndEnums.cs.

The ApiDefinition.cs is where you will define the API contract, this is the file that describes how the underlying Objective-C API is projected into C#. The StructsAndEnums.cs file is the file where you will enter any definitions that are required by the interfaces and delegates.

To bind your library you will have to create C# interfaces and annotate these interfaces with attributes to map the C# interface to the corresponding Objective-C class. Although it’s not too hard to do this, expect a lot of work for a moderate size Objective-C library.

To make this job easier, Xamarin introduced a new tool: Objective Sharpie, a very powerful binding definition generator for third party Objective C libraries to help provide APIs matching the .NET idioms.

“Objective Sharpie takes much of the manual work of translating Objective C APIs into binding definitions that are consumed by Xamarin’s binding tools. Download your third party library, point Objective Sharpie to its header files, and off you go.”

Podman– Command execution failed with exit code 125

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A complex system designed from scratch never works

A few years ago, I worked as an architect on a big mainframe rewrite. I still count it as one of my failures. Not because the technology was wrong, but because I couldn't convince the management team to simplify the approach. Years later, the organization is still struggling to get the new system up and running. I left the project at the time, because I couldn't put my name behind an approach that would take very long and cost a lot of money without a working system to show for it along the way. Gall’s Law That memory keeps coming back to me, because it's a textbook case of Gall's Law playing out in real life. Gall's Law , from John Gall's Systemantics , states it plainly: A complex system that works is invariably found to have evolved from a simple system that worked. A complex system designed from scratch never works, and it cannot be patched to make it work. You have to start over with a simple system that works. What does that mean in practice,...

The art of simplicity

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