Category Archives: development

.net, apple, development, software development

RemObjects previews native Apple Mac IDE for C#, .NET, Oxygene

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RemObjects is previewing a new native Mac IDE for its Oxygene and C# compilers. Oxygene is a Delphi-like language (in other words, a variant of Object Pascal) which targets iOS, Mac, Android, Windows Phone and Windows. RemObjects C# shares the same targets. Both can compile to .NET assemblies for Windows, or to Mono for cross-platform .NET, or to a Mac or iOS executable (using the LLVM compiler), or to Java bytecode for the Android Dalvik runtime. You can get both Oxygene and RemObjects  C# bundled in a product called Elements.

In the past, RemObjects has used Visual Studio as its IDE. While this is a natural choice for Windows users, much development today is done on the Mac. Requiring Mac users to develop in a Windows Virtual Machine adds friction, so RemObjects is now working on a native IDE for the Mac codenamed Fire.

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I gave Fire the briefest of looks. Here are some of the options for a new .NET application:

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Note the appearance of ASP.NET MVC 4, and even Silverlight.

Here are the options for a new Cocoa application:

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If you are developing for Cocoa, you can edit the resource file in Apple’s Xcode and use it in your application. I started a new C# Cocoa app, made a few changes and and then ran it from the IDE:

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I imagine Microsoft will be keeping an eye on tools like this – if it is not, it should – since they fit with the strategy of supporting Microsoft services on multiple devices. Visual Studio is a fine tool but if Microsoft is serious about cross-platform, it needs strong Mac-native development tools. Xamarin came up with Xamarin Studio, which is cross-platform for Windows and Mac, but the RemObjects approach also looks worth investigating.

PS The first release of RemObjects C# lacked full generic support, for which failing Xamarin and Mono founder Miguel de Icaza took RemObjects to task on Twitter. I was amused to see this in the changelog for April 2014:

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65764 Full support for Generics on Cocoa, as requested by Miguel

For more details on Fire, see here.

.net, azure, cloud computing, development, microsoft, software development, visual studio, web authoring

A note on Azure storage and downloading large files

I have written a simple ASP.NET MVC application for upload and download of files to/from Azure storage.

Getting large file upload to work was the first exercise, described here. That is working well; but what about download?

If your files in Azure storage are public, you can simply serve an URL to the file. If it is not public though, you have a couple of choices:

1. Download the file under application control, by writing to Response.OutputStream or using a FileResult action.

2. Issue a Shared Access Signature (SAS) to the client which enables it to retrieve the file directly from Azure storage. The SAS is sent as an URL argument which tells Azure storage that the request is authorised. The browser downloads the file directly, so it makes no difference to your web application if the file is large.

Note that if you use the first option, it will not work with large files if you simply call DownloadToStream or similar:

container.GetBlockBlobReference(FileName).DownloadToStream(Response.OutputStream);

Why not? Well, the way this code works is that it downloads the large file to the web server, then sends it to the browser. What if your large file is 5GB? The browser will wait a long time for the first byte to be served (giving the user an unresponsive page); but before that happens, the web application will probably throw an exception because it does not like downloading such a large file.

This means the SAS option is a good one, though note that you have to specify an expiry time which could cause problems for users on a slow connection.

Another option is to serve the file in chunks. Use CloudBlockBlob.DownloadRangeToStream to write to Response.OutputStream in a loop until the download is complete. Call Response.Flush() after each chunk to send the chunk to the browser immediately.

This gives the user a nice responsive download experience complete with a cancel option as provided by the browser, and does not crash the application on the server. It seems to me a reasonable approach if the web application is also hosted on Azure and therefore has a fast connection to Azure storage.

What about resuming a failed download? The SAS approach should work as Azure supports it. You could also support this in your app with some additional work since Resume means reading the Range header in a GET request. I have not tried doing this but you might find some clues here.

android, apple, cloud computing, development, iphone, microsoft

Microsoft repositions for a post-Windows client world

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Microsoft CEO Satya Nadella has penned a rather long public letter which sets out his ambitions for the company. It is not full of surprises for those who have been paying attention, but confirms what we are already seeing in projects such as Office for iPad: Microsoft is positioning itself for a world in which the Windows client does not dominate.

The statement that stands out most to me is this one (the highlighting is mine):

Apps will be designed as dual use with the intelligence to partition data between work and life and with the respect for each person’s privacy choices. All of these apps will be explicitly engineered so anybody can find, try and then buy them in friction-free ways. They will be built for other ecosystems so as people move from device to device, so will their content and the richness of their services

Microsoft is saying that it will build work/personal data partitioning into its applications, particularly one would imagine Office, and that it will write them for ecosystems other than its own, particularly one would imagine iOS and Android.

This is a big change from the Windows company, and one that I will expect to see reflected in the tools it offers to developers. If Microsoft is not trying to acquire Xamarin, you would wonder why not. It has to make Visual Studio a premier tool for writing cross-platform mobile applications. It also has to address the problem that an increasingly large proportion of developers now use Macs (I do not know the figures, but observe at some developer conferences that Windows machines are a rarity), perhaps via improved online developer tools or new tools that themselves run cross-platform.

Nadella is careful to avoid giving the impression that Microsoft is abandoning its first-party device efforts, making specific mention of Windows Phone, Surface, Cortana and Xbox, for example.

Our first-party devices will light up digital work and life. Surface Pro 3 is a great example – it is the world’s best productivity tablet. In addition, we will build first-party hardware to stimulate more demand for the entire Windows ecosystem. That means at times we’ll develop new categories like we did with Surface. It also means we will responsibly make the market for Windows Phone, which is our goal with the Nokia devices and services acquisition.

Here is another statement that caught my eye:

We will increase the fluidity of information and ideas by taking actions to flatten the organization and develop leaner business processes.

The company has become increasingly bureaucratic over the years, and that is holding back its ability to be agile (though some teams seem to move at high speed regardless; I would instance the Azure team as an example).

Nadella’s letter has too many flowery passages of uncertain meaning – “We will reinvent productivity for people who are swimming in a growing sea of devices, apps, data and social networks. We will build the solutions that address the productivity needs of groups and entire organizations as well as individuals by putting them at the center of their computing experiences.” – but I do not doubt that major change is under way.

.net, development, microsoft, software development

Supporting developers: how could Microsoft improve?

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Microsoft invests substantial resources in supporting developers; yet the last two topics I have explored in earnest – the Azure blob storage service, and ASP.NET MVC with Azure Active Directory integration – have been frustrating and difficult. Admittedly I am only an occasional developer, but I suspect my experience is common. What is going wrong, and how could Microsoft improve?

Among the problems I have encountered:

  • Abundant documentation of simple first steps with a vacuum for anything more advanced
  • Samples that do not run without tweaking
  • Samples designed for old versions of Visual Studio
  • Samples which use obsolete or deprecated libraries
  • Samples which are poor solutions for the problem they are supposed to address
  • Documentation or samples which use preview, beta or even alpha libraries. Microsoft sometimes seems to make more effort documenting what is in preview than what is fully released.
  • Posts on a topic which are out of date, but for which it is hard to find something current
  • Circular links – click here for more information – you get another article which links back to the first one, perhaps with an intermediate step
  • Poor quality responses to questions on official Microsoft forums

On the positive side, the reference documentation is not too bad. StackOverflow is a great resource and seems to attract higher quality responses (even sometimes from Microsoft staff) than the company’s own forums.

Here then are some of the improvements I would like to see:

1. A sharper distinction between what is in preview and what is production-ready. For any given problem, it would be great to find a clear statement of how you should address it for production now, with fully released and supported libraries, and another statement showing how you will be able to address it with the latest and greatest (but perhaps less stable) technology which is in preview.

2. For key teams in Microsoft to maintain sites which offer clearly delineated production and preview sections and which are kept rigorously up to date.

3. More short samples and fewer “this demonstrates everything” samples. Large samples are more difficult to install and study and have more complex dependencies.

4. Posts and their accompanying code inevitably go out of date and I do not favour removing them, which causes more difficulties than it solves (broken links). However it seems to me reasonable for teams to maintain a number of key samples for their product area and keep them up to date.

What am I missing – or am I complaining too much about what is normal in software development? As ever, I welcome your views.

apple, development, iphone, professional, software development

Apple’s Swift programming language: easy coding for OS X and iOS at last?

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Apple has announced a new programming language, called Swift. (There was already a language called Swift, used for parallel scripting, but Apple links to the other Swift in case you land on the wrong page. So far it looks like the other Swift has not returned the favour).

For as long as I can remember, serious Apple developers have had to use Objective-C, an object-oriented C that is not like C++. I have only dabbled in Objective-C but when I last tried it I was pleasantly surprised: memory management was no hassle and I found it productive. Nevertheless it is an intimidating language if you come from a background of, say, JavaScript or Microsoft .NET. Apple’s focus on Objective-C has left a gap for easier to use alternatives, though the main reason developers use something other than Objective-C, as far as I am aware, is for cross-platform projects. Companies such as Xamarin and Embarcadero (with Delphi) have had some success, and of course Adobe PhoneGap (or the open source Cordova) has had significant take-up for cross-platform code based on HTML and JavaScript.

I should mention that RAD (Rapid Application Development) on OS X has long been possible using the wholly-owned Filemaker, a database manager with a powerful scripting language, but this is not suitable for general-purpose apps.

Overall, it is fair to say that coding for OS X and iOS has a higher bar than for Windows because Apple has not provided anything like Microsoft’s C# or Visual Basic, type-safe languages with easy form builders that let you snap together an application in a short time, while still being powerful enough for almost any purpose. This has been a differentiator for Windows. Visual Basic is almost as old as Windows itself, and C# was introduced in 2000.

Now Apple has come up with its own equivalent. I am new to Swift as are most people outside Apple, but took a quick look at the book, The Swift Programming Language, along with the announcement details. A few highlights:

  • Swift is a type-safe language that compiles to native code using LLVM.
  • The IDE for Swift is Xcode. It supports Cocoa development (Apple’s user interface framework) via import of the existing Objective-C frameworks, which become Swift APIs via the import keyword:

import UIKit

  • You can mix Swift and Objective-C in a single project. In Objective C you can use #import to make Swift code visible and usable.
  • Swift is a C-family language and you will find familiar features like curly braces and semi-colons to terminate lines (though semi-colons are optional).
  • Swift uses reference counting for automatic memory management. There is rather complex section in the book about weak references and unowned references, to solve some of the problems inherent in reference counting.
  • Type inference is the preferred approach to declaring the type of a variable, but you can state the type if required. You can also declare constants.
  • Swift supports single inheritance for classes and multiple inheritance for protocols (protocols are more or less equivalent to interfaces in other languages).
  • There are advanced features including closures, generics, tuples, and variadic parameters. (I am not sure if “advanced” is the right word, but other languages such as C# and Java took a while to get these).
  • Swift has something like destructors which it calls deinitializers.
  • There is an interesting feature called Extensions which lets you add methods to any existing type. For example, you could extend Int with a prettyprint method and then call 3.prettyprint.
  • Swift variables are not normally nullable; they must have a value. However you can declare optional types (add a ?, such as Int?) that can be set to nil. You can also declare implicitly unwrapped optionals which can be nil, but once assigned a value cannot be nil thereafter.
  • Swift includes the AnyObject type which can represent anything.

Swift seems to me to have similar goals to Microsoft’s C#: easier and safer than C or C++, but intended for any use right up to large and complex applications. One of the best things about it is the smooth interoperability with Objective-C; this also saves Apple from having to write native Swift frameworks for its entire stack.

A smart move? I think so, though Swift is different enough from any other language that developers have some learning to do.

What difference will Swift make? Initially, not that much. Objective-C developers now have a choice and some will move over or start mixing and matching, but Swift is still single-platform and will not change the developer landscape. That said, Swift may make Apple’s platform more attractive to business developers, for whom C# or Java is currently more productive; and perhaps Apple could find ways of using Swift in places where previously you would have to use AppleScript, extending its usefulness.

If Apple developers were tempted towards Xamarin or Delphi for productivity, as opposed to cross-platform, they will probably now use Swift; but I doubt there were all that many in that particular group.

I would be interested to hear from developers though: what do you think of Swift?

.net, development, microsoft, mobile, software development, visual studio, windows

Xamarin 3.0 brings iOS visual design to Visual Studio, cross-platform XAML, F#, NuGet and more

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Xamarin has announced the third version of its cross-platform tools, which use C# and .NET to target multiple platforms, including iOS, Android and Mac OS X.

Xamarin 3.0 is a big release. In summary:

Xamarin Designer for iOS

Using a visual designer for iOS Storyboard projects, you can create and modify a GUI in both Visual Studio and Xamarin Studio (Xamarin’s own IDE). The designer uses the native Storyboard format, so you can open and modify existing files created in Xcode on the Mac. The technology here is amazing, since you iOS controls are rendered remotely on a Mac, and transmitted to the designer on Windows. See here for a quick hands-on.

Xamarin Forms

Xamarin has created the cross-platform GUI framework that it said it did not believe in. It is based on XAML though not compatible with Microsoft’s existing XAML implementations. There is no visual designer yet.

Why has Xamarin changed its mind? It was pressure from enterprise customers, from what I heard from CEO Nat Friedman. They want to make internal mobile apps with many forms, and do not want to rewrite the GUI code for every mobile platform they support.

Friedman made the point that Xamarin Forms still render as native controls. There is no drawing code in Xamarin Forms.

“The challenge for us in  building Xamarin forms was to give people enhanced productivity without compromising the native approach. The mix and match approach, where you can mix in native code at any point, you can get a handle for the native control, we’re think we’ve got the right compromise. And we’re not forcing Xamarin forms on you, this is just an option,”

he told me.

Again, there is a quick hands-on here.

F# support

F# is now officially supported in Xamarin projects. This brings functional programming to Xamarin, and will be warmly welcomed by the small but enthusiastic F# community (including, as I understand it, key .NET users in the financial world).

Portable Class Libraries

Xamarin now supports Microsoft’s Portable Class Libraries, which let you state what targets you want to support, and have Visual Studio ensure that you write compatible code. This also means that library vendors can easily support Xamarin if they choose to do so.

NuGet Packages

The NuGet package manager has transformed the business of getting hold of new libraries for use in Visual Studio. Now you can use it with Xamarin in both Visual Studio and Xamarin Studio.

Microsoft partnership

Perhaps the most interesting part of my interview with Nat Friedman was what he said about the company’s partnership with Microsoft. Apparently this is now close both from a technical perspective, and for business, with Microsoft inviting Xamarin for briefings with key customers.

.net, android, apple, development, microsoft, mobile, professional, software development, visual studio, windows

Hands on with Xamarin 3.0: a cross-platform breakthrough for Visual Studio

Today Xamarin announced version 3.0 of its cross-platform mobile development tools, which let you target Android and iOS with C# and .NET. I have been trying a late beta preview.

In order to use Xamarin 3.0 with iOS support you do need a Mac. However, you can do essentially all of your development in Visual Studio, and just use the Mac for debugging.

To get started, I installed Xamarin 3.0 on both Windows (with Visual Studio 2013 installed) and on a Mac Mini on the same network.

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Unfortunately I was not able to sit back and relax. I got an error installing Xamarin Studio, following which the installer would not proceed further. My solution was to download the full DMG (Mac virtual disk image) for Xamarin Studio and run that separately. This worked, and I was able to complete the install with the combined installer.

When you start a Visual Studio iOS project, you are prompted to pair with a Mac. To do this, you run a utility on the Mac called Xamarin.IOS Build Host, which generates a PIN. You enter the PIN in Visual Studio and then pairing is active.

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Once paired, you can create or open iOS Storyboard projects in Visual Studio, and use Xamarin’s amazing visual designer.

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Please click this image to open it full-size. What you are seeing is a native iOS Storyboard file open in Visual Studio 2013 and rendering the iOS controls. On the left is a palette of visual components I can add to the Storyboard. On the right is the normal Visual Studio solution explorer and property inspector.

The way this works, according to what Xamarin CEO Nat Friedman told me, is that the controls are rendered using the iOS simulator on the Mac, and then transmitted to the Windows designer. Thus, what you see is exactly what the simulator will render at runtime. Friedman says it is better than the Xcode designer.

“The way we do event handling is far more intuitive than Xcode. It supports the new iOS 7 auto-layout feature. It allows you to live preview custom controls. Instead of getting a grey rectangle you can see it live rendered inside the canvas. We use the iOS native format for Storyboard files so you can open existing Storyboard files and edit them.”

I made a trivial change to the project, configured the project to debug on the iOS simulator, and hit Start. On the Mac side, the app opened in the simulator. On the Windows side, I have breakpoint debugging.

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Now, I will not pretend that everything ran smoothly in the short time I have had the preview. I have had problems with the pairing after switching projects in Visual Studio. I also had to quit and restart the iOS Simulator in order to get rendering working again. This is an amazing experience though, combining remote debugging with a visual designer on Visual Studio in Windows that remote-renders design-time controls.

Still, time to look at another key new feature in Xamarin 3: Xamarin Forms. This is none other than our old friend XAML, implemented for iOS and Android. The Mono team has some experience implementing XAML on Linux, thanks to the Moonlight project which did Silverlight on Linux, but this is rather different. Xamarin forms does not do any custom drawing, but wraps native controls. In other words, it like is the Eclipse SWT approach for Java, and not like the Swing approach which does its own drawing. This is keeping with Xamarin’s philosophy of keeping apps as native as possible, even though the very existence of a cross-platform GUI framework is something of a compromise.

I have not had long to play with this. I did create a new Xamarin Forms project, and copy a few lines of XAML from a sample into a shared XAML file. Note that Xamarin Forms uses Shared Projects in Visual Studio, the same approach used by Microsoft’s Universal Apps. However, Xamarin Forms apps are NOT Universal Apps, since they do not support Windows 8 (yet).

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In a Shared Project, you have some code that is shared, and other code that is target-specific. By default hardly any code is shared, but you can move code to the shared node, or create new items there. I created XamFormsExample.xaml in the shared node, and amended App.cs so that it loads automatically. Then I ran the project in the Android emulator.

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I was also able to run this on iOS using the remote connection.

I noticed a few things about the XAML. The namespace is:

xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"

I have not seen this before. Microsoft’s XAML always seems to have a “2006” namespace. For example, this is for a Universal App:

xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x=http://schemas.microsoft.com/winfx/2006/xaml

However, XAML 2009 does exist and apparently can be used in limited circumstances:

In WPF, you can use XAML 2009 features, but only for XAML that is not WPF markup-compiled. Markup-compiled XAML and the BAML form of XAML do not currently support the XAML 2009 language keywords and features.

It’s odd, because of course Xamarin’s XAML is cut-down compared to Microsoft’s XAML. That said, I am not sure of the exact specification of XAML in Xamarin Forms. I have a draft reference but it is incomplete. I am not sure that styles are supported, which would be a major omission. However you do get layout managers including AbsoluteLayout, Grid, RelativeLayout and StackLayout. You also get controls (called Views) including Button, DatePicker, Editor, Entry (single line editor), Image, Label, ListView, OpenGLView, ProgressBar, SearchBar, Slider, TableView and WebView.

Xamarin is not making any claims for compatibility in its XAML implementation. There is no visual designer, and you cannot port from existing XAML code. The commitment to wrapping native controls may limit prospects for compatibility. However, Friedman did say that Xamarin hopes to support Universal Apps, ie. to run on Windows 8 as well as Windows Phone, iOS and Android. He said:

I think it is the right strategy, and if it does take off, which I think it will, we will support it.

Friedman says the partnership with Microsoft (which begin in November 2013) is now close, and it would be reasonable to assume that greater compatibility with Microsoft XAML is a future goal. Note that Xamarin 3 also supports Portable Class Libraries, so on the non-visual side sharing code with Microsoft projects should be straightforward.

Personally I think both the Xamarin forms and the iOS visual designer (which, note, does NOT support Xamarin Forms) are significant features. The iOS designer matters because you can now do almost all of your cross-platform mobile development within Visual Studio, even if you want to follow the old Xamarin model of a different, native user interface for each platform; and Xamarin Forms because it enables a new level of code sharing for Xamarin projects, as well as making XAML into a GUI language that you can use across all the most popular platforms. Note that I do have reservations about XAML; but it does tick the boxes for scaling to multiple form factors and for enormous flexibility.

apple, development, microsoft, mobile, professional, software development

Hands on with Cordova in Visual Studio

At TechEd this week, Microsoft announced Apache Cordova support in Visual Studio 2013. A Cordova app is HTML and JavaScript wrapped as a native app, with support for multiple platforms including iOS and Android. It is the open source part of Adobe’s PhoneGap product. I downloaded the preview from here and took a quick look.

There is a long list of dependencies which the preview offers to install on your behalf:

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and

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The list includes the Java SDK, Google Chrome and Apple iTunes. The documentation explains that Java is required for the Android build process, Chrome is required to run the Ripple emulator (so you could choose not to install if you do not require Ripple), and iTunes is required for deploying an app to an iOS device, though a Mac is also required.

The license terms for both Chrome and iTunes are long and onerous, plus iTunes is on my list of applications not to install on Windows if you want it to run fast. Chrome is already installed on my PC, and I unchecked iTunes.

Next, I ran Visual Studio and selected a Multi-Device Hybrid App project (I guess “Cordova app” was rejected as being too short and simple).

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An annoyance is that if you use the default project location, it is incompatible because of spaces in the path:

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The project opened, and being impatient I immediately hit Run.

When you build, and debug using the default Ripple emulator (which runs in Chrome, hence the dependency), Visual Studio grabs a ton of dependencies.

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and eventually the app runs:

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or you can debug in the Android emulator:

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A good start.

Microsoft has some sample projects for AngularJS, BackboneJS and WinJS. This last is intriguing since you could emulate the Windows Phone look and feel (or something like it) on Android on iOS, though it would look far from native.

The preview is not feature-complete. The only supported device targets are Android 4.x, IOS 6 and 7, Windows 8.x Store apps, and Windows Phone 8.x. Windows Phone debugging does not work in this preview.

.net, development, open source, software development, visual studio

Microsoft’s new open source direction for C# and .NET (and native compilation too): Anders Hejlsberg explains

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At the April 2014 Build conference Microsoft made some far-reaching announcements about its .NET platform and the C# programming language. Yes, there was talk of C# 6.0, the next version, but the real changes are more profound. Specifically:

C# and Visual Basic have a new compiler, itself written in C#, code-named Roslyn. Roslyn is not just a new compiler; Microsoft now calls it the “.NET Compiler Platform”.

There is a new commitment to open source for .NET projects. Microsoft formed the .NET Foundation to oversee existing open source projects, including  ASP.NET, Entity Framework, the Azure .NET SDK, and now Roslyn as well. “When it comes to development projects we are going to operate from the premise that open source is the default. Unless there are reasons why it does not work,” said C# lead architect Anders Hejlsberg.

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Note that open source does not mean chaos. It does mean that you can fork the project if you want – the Roslyn license is Apache 2.0 – but getting Microsoft to accept new features you have contributed will not be trivial. Hejlsberg makes the point that language features are easy to add, but impossible to take away, so extreme care is necessary.

Microsoft is also supporting cross-platform C# to a greater extent than it has done in the past. The most obvious sign of this is its cooperation with Xamarin, which provides C# compilers for iOS and Android. Xamarin’s Miguel de Icaza got a top billing at Build, and is also involved in the .NET Foundation.

There is more though. The idea of standardised C# is re-emerging:

“The last ECMA standard was C# 2.0. There wasn’t a lot of demand for it, but that demand has recently risen and we have re engaged with the ECMA community to produce a standard for C# 5.0,” said Hejlsberg.

This bears some unpacking. Why was there little demand for ECMA C#? Partly I would guess from the assumption the C# was firmly in Microsoft’s grip, with Java the obvious choice for cross-platform development. The main interest was from the Mono folk (Miguel de Icaza again), which implemented .NET for Linux and the Mac with some success, but nothing to disturb Java’s momentum.

The focus now though is on mobile, and interest in C# is stronger, mainly from Microsoft-platform developers reaching beyond Windows. There is also Unity, which uses C# as a scripting language for developing games for multiple platforms, including iOS, Android, Windows, Mac, Linux, Xbox, PS3 and Wii – PS4 is coming very soon.

Microsoft has now consciously embraced multiple platforms, as evidenced by Office for iOS as well as the Xamarin collaboration. “We want C#developers to build great applications across different form factors and different device platforms,” said Jay Schmelzer Director of Program Management for Visual Studio.

You might observe that this position has been forced on the company by the rise of iOS and Android, a view which likely has some merit, but the impact it has on C# and .NET itself is still real.

I asked Hejlsberg to unpack the difference between the Roslyn project and C# 6.0, bearing in mind that both are covered on the Roslyn open source site; you can see the current status of C# 6.0 and the next Visual Basic here.

Roslyn is the name for the project that encompasses the new C#compiler and the new VB compiler and the new language services that they share. C# 6.0 is the name of the next version of the C #language which will have a specification and which will have an implementation. We are implementing C# 6.0 on the Roslyn platform. We are not going to continue to evolve our old C++ C# compiler – the C# compiler was originally written in C++ and has been evolved up through C# 5.0. That is where we are going to retire that code base, and going forward versions of C# will be built on Roslyn and therefore will be built open source. Unlike previously where, boom. C# came down from the sky with a set of features, it is going to happen more organically now, people will submit pull requests, open up issues, and you will see us work on these features. You will see them from inception to fruition.

“The C# team, the Roslyn team, the VB team, their day to day workplace now is the open source site. That is where they check-in code. It is a community in the making.

Even that is not all. At Build, Microsoft also announced .NET Native, which is a native compiler for C# and Visual Basic, now in preview for x64 Store apps. What is the difference between .NET Native and the existing NGen native compiler for .NET? Over to Hejlsberg:

NGen is the native feature that we currently support. NGen is really, “I’m going to JIT [Just in time compile] your code and then snapshot all the data structures and dump them in a file so that I can quickly rebuild that file later when you run this particular application”. But it is the same code generator and all the same features, and JIT is still there. NGen is really a way to pre-cache the JIT output and therefore get better performance, but it adds to the size of your app because you still have all the assemblies and metadata and then the NGen image as well.

.NET Native is a completely different approach. Instead of the JIT we use the backend from the C++ compiler. You can think of it as a linker that takes as input assemblies, and as output produces a PE [Portable Executable] executable. In the process this linker or code generator will analyse all the IL [Intermediate Language] that goes into the application and it will apply a thing known as tree-shaking where it eliminates all of the code that will never execute based on known execution roots.

In other words, the public static main of your program and also whatever pieces of your app that you designate as reflectable, they also become roots. Based on that we produce an optimised exe, and into that exe we link the pieces of the framework that you are referencing. We link in a garbage collector [GC], and it looks to the operating system just like an exe. When you run it, it runs a local GC in there and it is as efficient really as C++ code.

There are some restrictions associated with .net native, mainly that you can’t just willy-nilly reflect on the whole world. You can’t just generate new code and ask for that to be jitted because they may not be a JIT compiler. We are considering allowing you to link in a JIT compiler, but there are certain execution environments which don’t permit jitting, like Xbox. If you use reflection in your lap you have to tell us what to keep reflectable, because otherwise we will optimise it away.

According to Schmelzer:

The preview out today is scoped to Store app x64 and ARM. We haven’t run into any technical limitation that shows it can’t be done across the breadth, it is just a matter of request and need.

Open source, native code compilation, and an innovative compiler: it adds up to huge changes for C# and .NET, positive ones as far as I can tell.

The Xamarin connection is intriguing though. Developers in general admire the technology as far as I can tell, but it is expensive, and paying out for a Xamarin subscription on top of maybe MSDN for Visual Studio is too much for some smaller organisations and does not encourage experimentation. Might Microsoft acquire Xamarin and build Visual Studio into an IDE targeting all the major mobile platforms, but with special hooks to Azure-hosted services?

That prospect makes sense to me, though it would be a shame if the energetic Xamarin culture became bogged down in big-company bureaucracy. Currently though: no news to report.

development, microsoft, windows

Getting animated: basics in Windows Store apps

I am not a designer and prefer to avoid things like animation as too difficult. On the other hand, I am writing an electronic card game and it looks bad if the cards move without any animation. There is also an issue in that animation is built into the standard controls, so if you do not animate your own parts of the user interface, it looks inconsistent.

Animation is more significant than it may first appear. You can think of it as a natural progression from a basic graphical user interface, along with things like full window drag. In the real world, objects do not just blink in and out of existence when they move from one spot to another.

My game is a bridge simulation so four cards are laid on the table in turn, at which point the winner of the four cards is calculated and the four cards gathered to form a “trick”. In my original implementation, the four cards simply disappeared at the end of the trick. How can I have it so that they smoothly gather themselves into a pile of four cards?

Like most things in Store apps, it proved a little more complex than I had thought. Originally, I put put each card in a separate cell of a layout grid. In Store apps, there is no built-in way to animate movement between grid cells, though users have come up with custom animations that do this. I thought it would be simpler to put the cards on a canvas instead.

I did some sums and positioned four Rectangle objects at the borders of the Canvas.

image

I want the Rectangle objects to slide smoothly into a pile in the centre. You do this in XAML with a Storyboard element. A Storyboard has child animation elements. When you call Storyboard.Begin() in your code, all the animations run. They run simultaneously unless one or more of the animations has a different BeginTime attribute. If you want a sequence of animations, you can either vary BeginTime, or use a KeyFrame animation which is designed for this.

There are several ways to do what I want. One is to animate Canvas.Top and Canvas .Left using a DoubleAnimation (the name indicates that it targets properties of type Double, not that anything happens twice). Note that if you this, the Storyboard.TargetProperty has to be in parantheses:

Storyboard.TargetProperty="(Canvas.Top)"

because it is an attached property. However, I chose to use a RepositionThemeAnimation. I found the way this works counter-intuitive. In XAML, you define a RepositionThemeAnimation with either or both a FromHorizontalOffset and a FromVerticalOffset. At runtime, the RepositionThemeAnimation moves the object to the offset position instantly, and then back to its starting point with animation. In other words, the animation itself does not move the object; unless you have AutoReverse set to True, in which case it does a second animation back to the offset position.

Once you grasp it, it is not difficult. Here is my Storyboard, set as a XAML Resource:

<Page.Resources>
    <Storyboard x:Name="TrickStoryboard">
        <RepositionThemeAnimation Storyboard.TargetName="CardLeft" SpeedRatio=".5"  FromHorizontalOffset="-185"/>
        <RepositionThemeAnimation Storyboard.TargetName="CardTop" SpeedRatio=".5"  FromVerticalOffset="-200"/>
        <RepositionThemeAnimation Storyboard.TargetName="CardRight" SpeedRatio=".5"  FromHorizontalOffset="185"/>
        <RepositionThemeAnimation  Storyboard.TargetName="CardBottom" SpeedRatio=".5"  FromVerticalOffset="200"/>
    </Storyboard>
</Page.Resources>

And here is my code to gather the trick:

this.CardTop.Margin = new Thickness(0, 185, 0, 0);
this.CardLeft.Margin = new Thickness(200, 0, 0, 0);
this.CardRight.Margin = new Thickness(-200, 0, 0, 0);
this.CardBottom.Margin = new Thickness(0, -185, 0, 0);
this.TrickStoryboard.Begin();

In other words, you move the objects to where you want them, and then apply the animation which moves them temporarily back to their starting point, then smoothly to their destination. At this point I should include a little video, but will leave you to imagine the four Rectangles above sliding and merging to a single central Rectangle.

Something to watch for here is how the animation impacts your code flow. The animation runs asynchronously, so if you have:

this.TrickStoryboard.Begin();
DoSomething();

then DoSomething runs before the animation completes. If this is not what you want, you can break at that point, and handle the StoryBoard.Completed event to resume. In my brief tests, StoryBoard.Completed always fires even if the animation gets interrupted, say by some other code that did something to the objects.

For more on this subject, read up on Animating your UI and get to know the different animation classes, Visual states, easing functions, RenderTransforms and more. It soon gets complex and verbose unfortunately, but on the plus side it is great to have animation baked into the framework, and the result is a more polished user interface.