Using RemObjects SDK and Data Abstract with Oxygene Nougat.

Nougat is, of course, designed to work with any existing Objective-C libraries out there, because it directly consumes and generates code for the Objective-C runtime. As such, it should come as no surprise that Nougat is ready to use RemObjects SDK and Data Abstract for Xcode, out of the box.

That said, with the new Alpha builds of RemObjects SDK and Data Abstract that we shipped on friday (build .1069), we have made a few improvements that make it even easier to get started with RO/DA in Nougat. These are three-fold:

Read-to-Use .fx files

Unlike .NET and Java, Cocoa libraries do not include easy to parse metadata for compilers to consume. Instead, it depends on .h files to define the available APIs — which is fine when consuming the libraries from a C compiler. Because .h files are slow and complicated to parse, Nougat introduces an intermediary format in the form of .fx files. You can think of an .fx file as “pre-compiled headers” file for a given framework or library; a set of metadata that represents all the information expressed in the framework’s .h files, but encoded in a way that it is easy and quick for the Oxygene compiler (and IDE toolchain) to process, when compiling, driving Code Completion etc.

While Nougat comes with the necessary tools to generate .fx files for any of your favorite third party libraries (and of course ships with .fx files for the supported base SDKs), that is an extra step we want to alleviate, so the new build of RODA/Xcode includes .fx file for those libraries out of the box. After installation, you will find the files next to the corresponding binaries in ./Bin.

All you need to do to use the SDK or Data Abstract from Nougat is to go to “Add Reference”, select the .fx file for your platform (i.e. OS X or iOS) to add a reference. That’s it.

libDA.fx Reference
From the .fx, Nougat will automatically know about all the types in the RO/DA library, and will take care of getting the static library and any dependencies linked in.

Static Libraries for OS X

In the past, RODA/Xcode included precompiled binaries in the form of a framework for OS X and static libraries for iOS. Frameworks are easier to deal with in Xcode, because they combine a binary with its accompanying header files, which is why we chose to ship OS X binaries as a framework. iOS does not support the framework format for third party libraries, so the choice there was easy: static libraries are the only option.

For Nougat, the benefits of a framework (on OS X) are diminished, because metadata is provided in the .fx file anyways, so a static library is just as easy to deal with, and has fewer files involved. For that reason, we have added a static library version of RODA/OS X to the product (in addition to the Framework). Xcode developers can choose to use either version, depending on their preferences (the static library has the benefit of being linkable straight into the executable, which is nice if you’re creating command line tools that use RO/DA); Nougat developers will mostly want to use the new static library alongside its .fx file.

CodeGen for Nougat

For pure Data Abstract use, you’re pretty much all set with the above, but if you’re building custom RemObjects SDK services that you want to talk to, there’s one more step missing: Interface code.

Talking to RO services depends on having strongly typed interfaces generated for your local proxy classes and any complex types you are passing back and forth between the client and the server — and until last week, RO/Xcode generated this code in Objective-C only.

That was not a complete showstopper for Nougat. Remember, Nougat can use any Objective-C library, so you could compile those files using Xcode and the use them from Nougat (in fact, that’s what i’ve been doing with for small RODA project i have been working on over the past few weeks). But that’s not ideal, of course.

The new alpha now includes native Nougat CodeGen for your services, so you can generate an Interface .pas file and add it straight to your Nougat project — as it should be.

The new CodeGen is exposed in three places:

  1. Of course the codegen2.exe command line utility has been updated, so if you generate code from the command line, you can use the /lang:nougat option to have interface files written for Nougat.
  2. Service Builder has also been expanded to support Nougat alongside all the other languages (that menu is getting mighty big!):

Service Builder
1. Finally, we also added Nougat CodeGen to our rodl2objc.app on the Mac (which is now really becoming overdue for a rename ;). While we were at it, we also revamped the UI for this tool a bit to make it (simple as it is) nicer to use, and look at:

rodl2objc
(and as the beta progresses, CodeGen will also be available directly inside the Visual Studio IDE, as well)

So with that you should be all set to build your first great client application for the Mac or iOS, using RemObjects SDK/Data Abstract and Oxygene “Nougat” over the holidays ;)

Let us know how it all works out!

yours,
marc

marc hoffman

Chief Architect and CEO here at RemObjects Software. Project Manager for Elements and lead developer of Fire, our awesome new development environment for the Mac.

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