Back in .NET Conf 2017 The Xamarin team already shared what’s going to be new with Xamarin Forms 3.0 and it actually surprised me. I was expecting some performance improvements, bug fixing and a big upgrade on XAML. But, what they announced focuses on enabling the usage of Xamarin.Forms in more ways and on more platforms. I was really hoping for XAML improvements, maybe add some cascading styling like how CSS works. Maybe sometime in the future, we’ll get it. For now, I’ll just use the XAMLCss by warapa. Anyway if you want to watch all sessions from .NET Conf 2017, you can check it out on Channel9. Going back, I really didn’t expect these new features, but definitely, I love it and really excited to try it out!
That’s why right now, I’m going to show to you one of the exciting features added to the Xamarin.Forms 3.0 that I think you’ll also love. I’m talking about Xamarin.Form’s macOS support.
One of the Xamarin team’s plan is to reach more platforms. That means UWP, iOS and Android are not only platform the Xamarin.Forms will be able to target from now on, they are also bringing macOS, GTK#, Linux and WPF!
Cocoa is Apple's native object-oriented application programming interface (API) for its desktop operating system macOS. Cocoa consists of the Foundation Kit, Application Kit, and Core Data frameworks, as included by the Cocoa.h header file, and the libraries and frameworks included by those, such as the C standard library and the Objective-C runtime. Cocoa applications are typically. You’ll be able to create a native macOS application using your Xamarin.Forms solution using Visual Studio for Mac or Xamarin Studio in just 3 quick steps! First step: Add a Cocoa App project. Right now, Xamarin.Forms template doesn’t have a Cocoa App initially. So, what you would do is to start Visual Studio for Mac or Xamarin.
You might think that it will be hard and will take a lot of time to integrate your Xamarin.Forms solution into the macOS project, but it’s not. Not at all. You’ll be able to create a native macOS application using your Xamarin.Forms solution using Visual Studio for Mac or Xamarin Studio in just 3 quick steps!
First step: Add a Cocoa App project
Right now, Xamarin.Forms template doesn’t have a Cocoa App initially. So, what you would do is to start Visual Studio for Mac or Xamarin Studio and open your existing Xamarin.Forms solution. Then, add a project into the solution by right-clicking the solution and selecting Add > Add New Existing Project.
You can then select Mac > App > Cocoa App and name it whatever you want, but ideally, the name has a suffix of .macOs.
Second Step: Add the Xamarin.Forms NuGet Package
You will have to add the Xamarin.Forms’ latest pre-release nuget package or specifically 2.4.0.282. To do this, right click the Cocoa App project that you just created and select Add > Add Nuget Packages.
Then, search for ‘Xamarin.Forms’ and make sure that the ‘Show pre-release packages’ is ticked. Click ‘Add’ to add Xamarin.Forms nuget package.
You will also need to update the Xamarin.Forms on your shared project and the version should be the same with what the Cocoa app have.
Third Step: Configure the Cocoa App Project
The first thing that you should do with your Cocoa app project is to add the shared project into your Cocoa app as a reference.
Then, open the Info.plist and remove the ‘Main storyboard file base name’ entry (Opened with XCode)
Or just open the Info.plist inside Visual Studio or Xamarin Studio by clicking it and leave the Main Interface blank.
The next one is to update your Main.cs’ Main method to initialize the AppDelegate:
Lastly, update the AppDelegate by changing the NSApplicationDelegate to FormsApplicationDelegate:
Initialize the Cocoa app window within the constructor:
Then inside the DidFinishLaunching method, initialize Xamarin.Forms and load the application:
You can now set your project as the startup project and run your macOS!
https://yellowdex819.weebly.com/blog/telegram-mac-app-store. Again, in just 3 quick steps, it’s done!
This is just a basic walkthrough since this is still on preview. Expect that there are still bugs and not ready for production. Not all nuget packages are compatible and surely, there are lots of UI features still not implemented, but this is a good start. For now, you can send your issues and problems that you encounter in this forum discussion: https://forums.xamarin.com/discussion/93585/preview-xamarin-forms-for-macos/p1
OS X includes three high-level native development environments that you can use for your application’s graphical user interface: Carbon, Cocoa, and Java. These environments are full-featured development environments in their own right, and you can write complete applications in any one of these environments.
In addition to these technologies, you can also use OpenGL, X11, Qt, Tcl/Tk, wxWidgets, and a number of other traditional UNIX graphics technologies when writing applications for OS X. In each case, there are tradeoffs. This chapter explains these tradeoffs and shows how they affect you as a programmer as well as your users.
Choosing a Native Application Environment
In the context of this document, Carbon, Cocoa, and Java are presented as a way to write a GUI wrapper for a UNIX-based tool.
Writing to these environments lets you build an application that is indistinguishable from any other native Mac app. The Java or Cocoa frameworks are probably the environments that you will use in bringing UNIX applications to OS X, although the Carbon frameworks are used by some developers. The following sections outline all three.
A good general rule is that if you decide to port your application from X11 to a native GUI environment, Carbon is a good choice for C and other procedural X11 applications, while Cocoa is a good choice if your application uses high-level toolkits such as Tcl/Tk or Qt. Cocoa is also a good choice for wrapping command-line applications with a GUI.
If you decide to port your cross-platform application to a native OS X GUI environment, you should carefully consider how best to do this port in a way that is maintainable. For some helpful tips, you should also read (Re)designing for Portability.
Cocoa
Cocoa is an object-oriented framework that incorporates many of OS X’s greatest strengths. Based on the highly-respected OpenStep frameworks, it allows for rapid development and deployment with both its object-oriented design and integration with the OS X development tools. Cocoa is divided into two major parts: Foundation and the Application Kit. Foundation provides the fundamental classes that define data types and collections; it also provides classes to access basic system information like dates and communication ports. The Application Kit builds on that by giving you the classes you need to implement graphical event-driven user interfaces.
Cocoa also provides file system abstraction that makes things such as file browsers look like Mac users expect. If you are developing a commercial application, you should use these. If you are developing an in-house application that will largely be used by people familiar with UNIX, the layout may be confusing, so these APIs may not be appropriate. See Presenting File Open and Save Dialog Boxes for more information.
The native language for Cocoa is Objective-C, which provides object-oriented extensions to standard C and Objective-C++. The Objective-C Programming Language describes the grammar of Objective-C and presents the concepts behind it. Objective-C is supported in gcc 2.95 and 3. Most of the Cocoa API is also accessible through Java. Cocoa is also the basis for AppleScript Studio, an application environment for script-based GUI development.
Additional Cocoa information, including sample code, can be found at http://developer.apple.com/. Cocoa documentation including tutorials is available at http://developer.apple.com/.
Benefits of Cocoa Development
- Rapid development environment
- Object-oriented framework design
- Excellent integration with OS X developer tools
- Very robust feature set
- Can take advantage of existing C, C++, Objective-C, and Java code
- Similar level of abstraction to high level toolkits such as Qt, Tcl/Tk, and so on
Best Mac Apps Native Cocoa Powder
Drawbacks of Cocoa Development
- Cross-platform deployment requires having a separate, non-Cocoa code base for the GUI portion
- Requires integrating Java, Objective C, or Objective C++ into your code base for the GUI layer
- Requires knowledge of Java, Objective C, or Objective C++
- Very different level of abstraction from raw X11 programming
- Potential performance penalties if used incorrectly
Example: Calling C or C++ Code With Cocoa
When designing an application from the ground up in Cocoa, you are in an object-oriented environment. You can also take advantage of Cocoa’s object-oriented nature when converting preexisting code, as you can use the Cocoa frameworks to wrap the functionality of C or C++ code.
The Objective-C language has been extended to understand C++. Often this is called Objective-C++, but the functionality remains basically the same. Because Cocoa understands Objective-C++, you can call native C and C++ code from Cocoa. This is one example of how you can take advantage of your code base while adding a Macintosh front end. An example is provided below of how Objective-C wraps together C, C++, and Objective-C++ functionality. Listing 4-1 shows the Objective-C main class.
Listing 4-1
main.m
This gets everything started when the user double-clicks the application icon. A call is then sent to invoke a
HelloController
object by the NIB, a file that holds interface information. The listings for HelloController.m
and HelloController.h
follow.Listing 4-2
HelloController.m
Listing 4-3
HelloController.h
The communication between the C, C++, and the Objective-C code is handled as shown in Listing 4-4. The header file
SayHello.h
is shown in Listing 4-5. Apple news app macos.Listing 4-4
SayHello.mm
Listing 4-5
SayHello.h
The C++ class wrapped by these Cocoa calls is shown in Listing 4-6. The header file,
FooClass.h
, is shown in Listing 4-7.Listing 4-6
FooClass.cpp
Listing 4-7
FooClass.h
You should be careful when writing code using Cocoa, because the same constructs that make it easy for the developer tend to degrade performance when overused. In particular, heavy use of message passing can result in a sluggish application.
The ideal use of Cocoa is as a thin layer on top of an existing application. Such a design gives you not only good performance and ease of GUI design, but also minimizes the amount of divergence between your UNIX code base and your OS X code base.
Carbon
Carbon is an environment designed to bring existing Mac OS applications to OS X. It can be used to bring an X11 application to a native OS X environment, since the basic drawing primitives are at a similar level of abstraction.
Carbon also offers relatively straightforward file I/O with a few enhancements that are unavailable through POSIX APIs, such as aliases (which behave like a cross between a symbolic link and a hard link). Carbon presents the file system differently to the user than UNIX applications do. This is the layout that Mac users are used to seeing, and thus you should use it if possible when developing a commercial application for broad-scale deployment.
However, if your users are predominantly UNIX users (for example, if you are an in-house developer in a corporate environment), the use of the Carbon file API may not be appropriate, since volumes appear as they do in the Finder, rather than being organized according to the file system hierarchy.
Benefits of Carbon Development
- Well-documented feature set
- Integration with OS X developer tools
- Very robust feature set
- Simple C and C++ integration
- Similar abstraction level to X11
- Procedural design rather than object-oriented
Best Mac Apps Native Cocoa Butter
Drawbacks of Carbon Development
- No cross-platform deployment without a separate non-Carbon code base
- Slightly more effort required to take advantage of native OS X technologies
- Procedural design rather than object-oriented
In case you’re wondering, that isn’t a typo. Procedural design in a GUI can be both a benefit and a drawback.
Procedural design can be a benefit in terms of being able to easily integrate into any environment, regardless of language. It is also a benefit because it fits many styles of graphical programming well.
Procedural design can be a drawback, however, when dealing with more complex GUI designs where it would be more convenient to have the methods more closely tied to the data on which they operate.
Lower-Level Graphics Technologies
With some code it is simple to abstract the display code from the underlying computational engine, but often this isn’t the case. Especially for graphics-intensive applications, you may want to take advantage of directly calling the core graphic functionality of your targeted operating system. You still need to wrap this functionality in a higher-level API to display it to the screen and allow user interaction, but for times where you need to push pixels in very specific ways, OS X offers you access to three first-class graphics technologies: Quartz, OpenGL, and QuickTime.
Quartz
Quartz is the graphical system that forms the foundation of the imaging model for OS X. Quartz gives you a standards-based drawing model and output format. Quartz provides both a two-dimensional drawing engine and the OS X windowing environment. Its drawing engine leverages the Portable Document Format (PDF) drawing model to provide professional-strength drawing. The windowing services provide low-level functionality such as window buffering and event handling as well as translucency. Quartz is covered in more detail in Mac Technology Overview and at (http://developer.apple.com/).
Benefits of using Quartz
- PostScript-like drawing features
- PDF-based
- Included color management tools
- Unified print and imaging model
Drawbacks to using Quartz
- No cross-platform deployment
![Best mac apps native cocoa butter Best mac apps native cocoa butter](/uploads/1/3/4/0/134047581/633264708.png)
OpenGL
OpenGL is an industry-standard 2D and 3D graphics technology. It provides functionality for rendering, texture mapping, special effects, and other visualization functions. It is a fundamental part of OS X and is implemented on many other platforms.
Given its integration into many modern graphics chipsets and video cards, it is of special interest for programs that require intricate graphic manipulation. OpenGL’s homepage gives more information on the technology in general at http://www.opengl.org.
Apple’s OpenGL page, at https://developer.apple.com/devcenter/mac/resources/opengl/, gives more information on how it is integrated into OS X and explains the enhancements that the OS X OpenGL implementation provides.
Benefits of using OpenGL
- Cross-platform technology
- Native OS X integration
- Included with every installation of OS X
- Very robust feature set for handling graphics
Drawbacks to using OpenGL
- Some level of integration at an application level is required
QuickTime
QuickTime is a powerful multimedia technology for manipulating, enhancing, storing, and delivering graphics, video, and sound. It is a cross-platform technology that provides delivery on Mac OS as well as Windows. More information on the technology can be found at http://developer.apple.com/quicktime/.
Benefits of using QuickTime
- Robust feature set for manipulating sound and video
- Cross-platform development
Drawbacks to using QuickTime
- Not supported on other UNIX-based systems.
Note that while QuickTime itself is not supported on UNIX-based systems, the QuickTime file format is supported by various third-party utilities.
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