Tag Archives: xamarin

android, mobile, software development, tech, xamarin

Using the Xamarin WebView for programmatic display of HTML content

Xamarin Forms is a key framework for C# and .NET developers since it lets you target Android, iOS and to some extent Windows (UWP and therefore Windows 10 only) with maximum code reuse. I have a longstanding interest in embedded web browser controls and was glad to see that Xamarin Forms supports a capable WebView control. The WebView wraps Chrome on Android, Safari on iOS, and Edge on UWP.

I did a quick hands-on. In this example (running in the Android emulator on Hyper-V, of course), the HTML is generated programmatically and the CSS loaded from local storage. I also added some script to show the User Agent string that identifies the browser.

image

There are a few things needed to make this work. Some XAML to put the WebView on a page. Then to load content into the WebView you need an HTMLWebViewSource object. If you are loading external files, you must set the BaseUrl property of this object as well as the HTML itself. The BaseUrl tells the control where to look for files that have a relative address. This varies according to the target platform, so you use the Xamarin Forms Dependency Service to set it correctly for each platform.

In Visual Studio, you place the files you want to load in the appropriate folder for each platform. For Android, this is the Assets folder.

That is about all there is to it. As you can see from the above screenshot, I wrote very little code.

The WebView control can also display PDF documents. Finally, there is an EvaluateJavaScriptAsync method that lets you call JavaScript in a WebView and read the results from C#.

This JavaScript bridge is a workaround for the most obvious missing feature, that you cannot directly read the HTML content from the WebView. If this is a full programmatic solution and you generate all the HTML yourself, you can add JavaScript to do what you want. If the user is allowed to navigate anywhere on the web, you cannot easily grab the HTML; but this could be a good thing, in case the user entered a password or is viewing confidential data. You can grab the destination URL from the Navigating event and read it separately if necessary. But the intent of the control is to let you create rich applications that take advantage of the browser’s ability to render content, not to invade a user’s privacy by tracking their web browsing.

microsoft, mobile, visual studio

Xamarin Challenge shows bumps in Microsoft’s path to cross-platform mobile

Microsoft ran a Xamarin Challenge over on Paul Thurrott’s site. The idea was to demo how to build a cross-platform mobile app with Microsoft’s cross-platform mobile toolkit.

The challenge was in three steps. You build a weather app, complete with crash analytics on the Visual Studio Mobile Center.

image

Someone did a lot of work on this, and the app looks pretty and works nicely once you get it running.

Despite this, I am not sure that the challenge was altogether successful. It is a step-by-step which in theory involves no developer expertise as you simply copy and paste code into your project. I am not sure that is the best way to learn, but that is by the by. I doubt that learning how to code for Xamarin was the primary goal of the challenge. I’d guess it was more about showing how easily you can build a cross-platform app (Android, iOS and Windows UWP) using Xamarin, C# and Visual Studio 2017.

Well, in fact a little bit of developer expertise was required to complete the challenge, because the step by step instructions did not quite work (in my experience). I did not make a note of all the times I had to do something not in the given steps, but there were many occasions, the main issues being around using the Visual Studio Android emulator, NuGet package management, and a few small tweaks to the code itself. The code as given made no allowance for the cloud services it called being offline, or the connection to the internet not being available, but would simply crash in this case.

The challenge could be an excellent resource for Microsoft and Xamarin if the company drills down into the problems developers experienced trying to complete the challenge, recorded in this forum thread. Here are a few examples:

Myself and 5 other developers in our office attempted the challenge and none of us have been able to get past the first challenge. We are not Microsoft Visual Studio experts so we had hoped following the provided instructions would be sufficient.

—

The upload was failing on a discrepancy between 2 different versions of the Json package, which somehow had crept into the project. Installing over 40 updates in Nuget resolved this.

Many thanks for running this challenge –this was very useful and worthwhile. I just wish modern development did not feel like trying to dance on a mile high stack of chairs with a leg missing on the bottommost one!

—

I got a late start on the challenge and was able to complete part 1 pretty quickly but was only able to run the UWP locally. I cannot seem to get either the Windows mobile emulator or Android emulators to run successfully. I can’t deploy to the Window Mobile emulator, it returns an error indicating the emulator failed to start. As for the Android emulator, it launches, but the emulator does not have a connection to the network, so the application encounters an exception.

Note that those posting to the forum were more likely to be the ones with problems; there could in theory be many others who breezed through without any issues. But as one participant writes, “I’d be interested in what percentage of participants actually got to the end of the challenge with no problems.”

I like Xamarin; it does an amazing job in enabling cross-platform development with C# and it would be my tool of choice for cross-platform mobile development. It is not always straightforward though, and the kinds of issues experienced by the challenge participants illustrate what can go wrong.

If you just use the native toolkits, such as Android Studio and Xcode, you will have a smoother experience, but of course miss out on the productivity benefit of cross-platform code. That is the trade-off you make.

.net, android, apple, microsoft, mobile, professional, software development, xamarin

Xamarin Evolve: developers enjoy the buzz around cross-platform coding with C#

“It’s like a Microsoft developer event back when they were good,” one exhibitor here at Xamarin Evolve in Atlanta told me, and I do see what he means. There is plenty of buzz, since Xamarin is just three years old as a company and growing fast; there is the sense of an emerging technology, and that developers are actually enjoying their exploration of what they can do on today’s mobile devices.

Microsoft is an engineering-led company and was more so in its early days. The same is true of Xamarin. It also also still small enough that everyone is approachable, including co-founders Miguel de Icaza and Nat Friedman. The session on what’s new in Xamarin.Mac and Xamarin.iOS was presented by de Icaza, and it is obvious that he is still hands-on with the technology and knows it inside out. Developers warm to this because they feel that the company will be responsive to their needs.

image

Approachability is important, because this is a company that is delivering code at breakneck speed and bugs or known issues are not uncommon. A typical conversation with an attendee here goes like this:

“How do you find the tools?” “Oh, we like them, they are working well for us. Well, we did find some bugs, but we talked to Xamarin about them and they were fixed quickly.”

Xamarin’s tools let you write C# code and compile it for iOS, Android and Mac. If you are building for Windows Phone or Windows, you will probably use Microsoft’s tools and share non-visual C# code, though the recently introduced Xamarin Forms, a cross-platform XML language for defining a user interface, builds for Windows Phone as well as iOS and Android.

The relationship with Microsoft runs deep. The main appeal of the tools is to Microsoft platform developers who either want to use their existing C# (or now F#) skills to respond to the inevitable demand for iOS and Android clients, or to port existing C# code, or to make use of existing C# libraries to integrate with Windows applications on the server.

That said, Xamarin is beginning to appeal to developers from outside the Microsoft ecosystem and I was told that there is now demand for Xamarin to run introductory C# classes. Key to its appeal is that you get deep native integration on each platform. The word “native” is abused by cross-platform tool vendors, all of whom claim to have it. In Xamarin’s case what it means is that the user interface is rendered using native controls on each platform. There are also extensive language bindings so that, for example, you can call the iOS API seamlessly from C# code. Of course this code is not cross-platform, so developers need to work out how to structure their solutions to isolate the platform-specific code so that the app builds correctly for each target. The developers of Wordament, a casual game which started out as a Windows Phone app, gave a nice session on this here at Evolve.

Wordament has an interesting history. It started out using Silverlight for Windows Phone and Google App Engine on the server. Following outages with Google App Engine, the server parts were moved to Azure. Then for Windows 8 the team ported the app to HTML and JavaScript. Then they did a port to Objective C for iOS and Java for Android. Then they found that managing all these codebases made it near-impossible to add features. Wordament is a network game where you compete simultaneously with players on all platforms, so all versions need to keep tightly in step. So they ported to Xamarin and now it is C# on all platforms.. 

I digress. The attendees here are mostly from a Microsoft platform background, and they like the fact that Xamarin works with Visual Studio. This also means that there are plenty of Microsoft partner companies here, such as the component vendors DevExpress, Syncfusion, Infragistics and ComponentOne. It is curious: according to one of the component companies I spoke to, Microsoft platform developers get the value of this approach where others do not. They have had only limited success with products for native iOS or Android development, but now that Xamarin Forms has come along, interest is high.

Another Microsoft connection is Charles Petzold – yes, the guy who wrote Programming Windows – who is here presenting on Xamarin Forms and signing preview copies of his book on the subject. Petzold now works for Xamarin; I interviewed him here and hope to post this soon. Microsoft itself is here as well; it is the biggest sponsor and promoting Microsoft Azure along with Visual Studio.

Xamarin is not Microsoft though, and that is also important. IBM is also a big sponsor, and announced a partnership with Xamarin, offering libraries and IDE add-ins to integrate with its Worklight mobile-oriented middleware. Amazon is here, promoting both its app platform and its cloud services. Google is a sponsor though not all that visible here; Peter Friese from the company gave a session on using Google Play Services, and Jon Skeet also from Google presented a session, but it was pure C# and not Google-specific. Salesforce is a sponsor because it wants developers to hook into its cloud services no matter what tool they use; so too is Dropbox.

  image

Most of the Xamarin folk use Macs, and either use Xamarin Studio (a customised version of the open source MonoDevelop IDE), or Visual Studio running in a virtual machine (given that the team mostly use Macs, this seems to me the preferred platform for Xamarin development, though Visual Studio is a more advanced IDE so you will probably end up dipping in and out of Windows/Mac however you approach it).

Xamarin announced several new products here at Evolve; I gave a quick summary in a Register post. To be specific:

  • A new fast Android emulator based on Virtual Box
  • Xamarin Sketches for trying out code with immediate analysis and execution
  • Xamarin Profiler
  • Xamarin Insights: analytics and troubleshooting for deployed apps

Of these, Sketches is the most interesting. You write snippets of code and the tool not only executes it but does magic like generating a graph from sequences of data. You can use it for UI code too, trying out different fonts, colours and shapes until you get something you like. It is great fun and would be good for teaching as well; maybe Xamarin could do a version for education at a modest price (or free)?

image

I am looking forward to trying out Sketches though I have heard grumbles about the preview being hard to get working so it may have to wait until next week.

image

android, ios, mobile, software development

Testing mobile apps: Xamarin goes live with Test Cloud for iOS and Android (but no Windows Phone)

Testing a mobile app is challenging, thanks to operating system fragmentation combined with diversity of hardware. In April 2013 Xamarin acquired a company called LessPainful, specialists in functional testing for mobile apps, which had created a mobile app testing tool called Calabash. Calabash is based on Cucumber, and lets you define test steps and then combine them into natural language tests. LessPainful also had a cloud testing service which let you run tests on remote physical devices and see visual test reports.

Eighteen months on, Xamarin has now gone live with Test Cloud, and has announced some big names which it says are using the service, including Dropbox, Flipboard and eBay.

There are currently 1036 devices (the number changes regularly) in the Test Cloud, including 273 iOS and 763 Android (Windows Phone is not supported, but Amazon’s Fire Phone and Kindle Fire does appear in the list).

image

You write your tests either in Calabash or in C#, upload your app and the tests to Test Cloud, wait a while, and then get notification that the tests are done and a report ready to view.

image

You can simulate events such as changes in location, device rotation, network dropouts, and of course user interactions like taps and gestures. You get screenshots and performance data (memory and CPU usage) for each test step.

You can also integrate with CI (Continuous Integration) systems like TFS, Jenkins and TeamCity to automate testing.

Writing and maintaining tests is hard work, of course, but for businesses that can afford the investment in both time and money, Test Cloud is likely to be a great improvement on manually gathering up as many devices as you can find and installing your app on all of them.

The cost is significant though, starting at $1000 per month for up to 2 apps and 200 device hours. You have to pay annually too, so it looks like a strategy of just buying one month towards the end of your development cycle will not work.

That said, I have been told that Xamarin will be coming out with an Indie version in the future that has a lower price.

microsoft, mobile, mono, software development, visual studio

Xamarin announces large round of funding, plans international expansion

It is a case of “right time, right place” for Xamarin, as it scoops up Windows developers who need either to transition to iOS and Android, or to add mobile support to existing applications. You can also port applications to the Mac with its cross-platform development framework based on C#; no bad thing as Mac sales continue to boom.

image

Xamarin also fits with Microsoft’s new strategy, as I understand it, which is to provide strong support for iOS and Android for applications such as Microsoft Office, and services such as those hosted on Microsoft Azure.

Now the company has announced an additional $54 million of funding, which CEO Nat Friedman tells me is “the largest round of financing achieved by any mobile platform company ever”.

The financing comes from “new and existing investors, including Lead Edge Capital, Insight Venture Partners, Charles River Ventures, Ignition Partners, and Floodgate.”

What will the money be spent on? “Two things,” says Friedman. “We’re planning to expand our sales and marketing into Europe. We’re opening a sales office in London in the Fall. We did a roadshow with Microsoft in Europe and it was extremely successful. Second, we’re going to invest in improving the quality of our platforms.”

Friedman notes that mobile should not be considered a development niche. “Our view is that in the future all software will be mobile software in some way or another, when you build an application it will have to have some kind of mobile surface area.”

A few other points to note. One is that Xamarin Forms, recently introduced, has been a big hit with developers. “The Xamarin Forms forum has been our most popular forum,” says Friedman. “We’ve been really surprised.”

The company used to promote the idea of avoiding cross-platform code for the user interface, but then introduced Xamarin Forms as a cross-platform GUI framework, arguing that because it uses only native controls, it avoids the main drawbacks of the idea.

Some of the funding then will go into improving Xamarin Forms and tools to work with the framework.

Another key area is Visual Studio integration. The acquisition of the Visual Studio integration team from Clarius Consulting, in May 2014, is also significant here, since Clarius had strong expertise in this area.

Might Microsoft try to acquire Xamarin? Interesting question, and one which Friedman is not in a position to discuss; I am not a financial expert but would guess that Xamarin’s independent expansion increases its ability to be independent, though investors may be hoping to reap the rewards of an acquisition, who knows?

apple, development, iphone, professional, software development

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

5 Comments

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

3 Comments

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.

image

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.

image

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

image

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.

image

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).

image 

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.

image

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.

.net, android, apple, microsoft, software development, windows

Microsoft Build goes nuts over Xamarin’s C# and .NET for iOS and Android

2 Comments

Xamarin’s Miguel de Icaza was booked for a standard session room at Build, Microsoft’s developer conference in San Francisco, but the session was moved to the keynote room because of demand. I am not sure how the likely demand was calculated, but it was possibly something to do with the event app that lets attendees plan their agenda.

It was just as well that the session got moved.

image

The attendance at the session mirrored my observation that Xamarin’s stand in the third-party partner exhibition was drawing more attention than any other. Xamarin’s tools let developers port applications to iOS and Android while still using C# and the .NET Framework.

image

I am not sure what to conclude from the obvious high level of interest in compiling apps for iOS and Android. You can interpret this as good news for Microsoft, in that it keeps developers working in .NET and with easy access to the libraries that support Microsoft services; or as bad news, in that it shows how many developers are moving towards non-Microsoft platforms in their app deployments.

It was the second time today that de Icaza appeared on the keynote stage. Earlier he stood there with Anders Hejlsberg, the author of C#.

image

It has been a long journey, from the time when Mono (the open source implementation of .NET founded by de Icaza) was viewed with distrust by Microsoft (as far as I could tell), as an open source competitor to the official version.

Now there is talk of whether Microsoft might acquire Xamarin – of which there is no news here at Build, I should emphasise.

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

Microsoft Build Sessions published: Windows Phone XAML and HTML/JS apps, new Azure APIs and more

2 Comments

Developing for Windows Phone is now closer to developing for the Windows 8 runtime, according to information from Microsoft’s Build sessions, just published.

Build is Microsoft’s developer conference which opens tomorrow in San Francisco.

image

Building a Converged Phone and PC App using HTML and JavaScript states that “An exciting part of Windows Phone 8.1 is that you can now start building applications natively in HTML and JavaScript.”

Other sessions refer to the Common XAML UI Framework, which seems to refer to a shared UI framework for Windows Phone and WIndows 8, but using XAML rather than HTML and JavaScript.

This is in addition to Silverlight, not instead, judging by this session:

We’ve been doing a lot of work with new converged XAML app support on Windows Phone 8.1, but what about legacy Windows Phone Silverlight XAML based apps?  Come learn about all the new features we’ve enabled with Silverlight 8.1.

Microsoft has also come up with new APIs for applications that integrate with its Azure cloud platform and with Office 365. The Authentication library for Azure Active Directory lets you build both Windows and mobile applications that authenticate against Azure Active Directory, used by every Office 365 deployment. There is also talk of using Azure for Connected Devices, meaning “Internet of Things” devices using Azure services.

Some other sessions which caught my eye:

Connected Productivity Apps: building apps for the SharePoint and Office 365 platform.

What’s new in WinJS: the road ahead. XAML vs HTML/JS is a big decision for Windows developers.

Anders Hejlsberg on TypeScript

Automating Azure: “The Azure Management Libraries and Azure PowerShell Cmdlets allow this type of automation by providing convenient client wrappers around the Azure management REST API”

Authentication library for Azure Active Directory: The Active Directory Authentication Library (ADAL)

Panel discussion on desktop development: is there a future for WPF? Maybe some clues here.

Miguel de Icaza gets a session on going mobile with C# and Xamarin. I recall when de Icaza ran sessions on Mono, the open source implementation of the .NET Framework which he initiated shortly after Microsoft announced .NET itself, in nearby hotels at Microsoft events; now he is inside.

Learning from the mistakes of Azure: Mark Russinovich on what can go wrong in the cloud.

Looks like both cloud and apps for Windows Phone/Windows 8 are big themes at Build this year.