I am reading about out of browser silverlight applications and cannot think of many use cases for it. One only scenario i can think of is where your application need ability to work offline and when its online then it can synchronize with the server ( or something). But in that case I can simply have a WPF ( or old style Winform) application that is communicating with server. Can anyone help me understanding better uses case for these out of browser applications.
There are some good answers on SO that should give you some background on Silverlight OOB vs. WCF:
Silverlight OOB vs WPF ClickOnce
What are the advantages of silverlight out of browser over wpf or vice versa?
I will add that as a corporate developer Silverlight has its benefits over WPF or WinForms in that there is no need to install the full .NET Framework to run the applications. OOB gives a more desktop like feel w/ Start Menu icons and easy access w/out the need of visiting a URL to run the application. There are a few things that you can do in elevated trust in OOB that you can't do in the browser (though that is changing w/ full trust rights both in-browser and OOB in SL5).
Here's some of the details on the features you get access to w/ elevated trust:
http://msdn.microsoft.com/en-us/library/ee721083(VS.95).aspx
It really comes down to your usage scenarios, ease of framework deployments and the environment you are developing for. Each set of tools has its benefits and drawbacks.
Related
We need to create an application that can be used via the browser but that can also be used while offline.
The browser Version will be used by our customer to do calculations. Each customer needs to log into the application with a username and Password.
The offline version will be used by our own employees. They need to be able to use this Version while not connected to a Network.
The data that is needed for the application will be stored in XML files.
We are mainly programming with C# and the .NET-Framework. We thought about using WPF for the client version.
I have read that you can use Silverlight or XBAP to create a browser Version of the WPF application. AFAIK Silverlight is a dying Technology. How about XBAP? Would you still invest into this Technology?
The other solution would be to create two front end applications: The WPF application as an offline application and a web application (e.g. ASP.NET MVC) as a web application. Thought, this would mean that we would have to create two frontends (more work).
Is there another alternative?
Would it be better to create an HTML/JavaScript application (e.g. with AngularJ or something similar)?
As a former Silverlight Developer I can only recommend not to use Silverlight for new application development. Microsoft has suspended the further development of Silverlight and you will not get any new features (only security fixes). I really liked the technology and the similarity to WPF but for me it is deprecated.
Even some Browsers (like Chrome) do not support Silverlight anymore and you need a workaround to get it running (See also Chrome doesn't support silverlight anymore? How to solve this?)
Develop a Backendsystem that provides a REST-API (using ASP.NET WebApi as an example) for your clients and develop a Browser client application using modern HTML/CSS/JavaScript Frameworks. If needed/required a desktop application using WPF that consumes the REST-API.
Silverlight may be dying, but that does not mean you should avoid using it. Silverlight is still a viable technology that you can use, however browser trends seem to be phasing out Silverlight support. As far as I know, Microsoft Edge browser is no longer supporting Silverlight, so you will need to use Internet Explorer. This isn't the end of the world, but it's something to think about.
As for WPF, this too is being replaced by Windows Universal Apps, albeit slowly. However this isn't too much of an issue as the skills you have learnt in WPF are easily transferrable. WPF itself is not receiving as many new features as it used to, you could say it's finished.
It isn't always easy to keep up with the latest trends, and there will always be something cool and hip just around the corner, however one thing is for sure, the .NET Platform, including the new refactored Universal App APIs are here to stay, and won't die any time soon.
The current trend sees Web Technologies, such as ASP.NET playing a much bigger role than traditional desktop/tablet/phone applications. I would say that developing for a web browser is certainly a popular choice.
That being said, Windows Universal Apps is also a good choice, in fact, any technology that makes use of the .NET Framework is ideal.
As for my recommendation, I would suggest looking into an ASP.NET web application or Web API to which a desktop application, such as WPF (still a viable technology for enterprise applications) or Universal Windows App can hook into. An ideal scenario would be that both applications share the same back-end code, which is certainly possible as they both use the .NET Framework.
For your requirements, it may even be possible to avoid having to create a desktop application altogether, a web application can be hosted on a machine on the local network and clients can still use the web app. This is assuming that these clients don't have internet access of course.
TL;DR: .NET is legit, use ASP.NET.
I want to know what are the differences between a WPF Browser Application and WPF Desktop Application. I know that the browser application runs on IE and FF, but about the technology, is the same? I mean, we can do exactly the same by the two ways? (Of course, maybe with different UI)
I have this doubt because I'm looking for a book about WPF Browser Applications, but I only see books about WPF (I don't know if is in general or is only for desktop applications :S)
A WPF Browser Application uses exactly the same framework as a WPF desktop application and could run with the same UI, but with restrictions on trust which means that some APIs are not available. There a number of challenges in developing Browser application. A Browser app must be signed with a certificate. Some of the trust restrictions are not enforced at compile time and are only discovered at run time.
In the time since Browser Applications were first introduced, Microsoft developed Silverlight which uses a similar though not identical XAML technology. Silverlight is easier to deploy than a WPF Browser Application and may be appropriate depending upon your requirements.
A Browser Application not only runs in the browser but also with less authority. If you need to read and write local files then go WPF. Browser is good is you want rapid deployment to lots of PCs. Other wise I will take WPF Desktop every time. Most WPF books with have a chapter on XBAP. I like McDonald from Apress.
I have been using WPF for a while, and I keep on realizing again and again that Microsoft invests its efforst in Silverlight, not in WPF (RIA Services, default theme, controls and more).
I thought it might be a good idea to migrate to Silverlight (i.e. creating standalone desktop apps with Silverlight 4.0), the question is whether this is possible or not.
BTW, I think LightSwitch applications are generated with Silverlight as standalone desktop apps.
From MSDN:
Silverlight 3 applications are no longer restricted to running in a browser. They can be run in a browser or it they can be detached from the browser and run from the desktop. These out-of-browser applications allow you to bring the richness of Silverlight 3 applications directly to the desktop without the restriction of running within a browser.
Link: Building An Out-of-Browser Client With Silverlight 3
It is possible to create standalone desktop apps(Out of browser apps) with silverlight version 3.0 or higher and it works great. Now it is also possible to install the out of browser app even without opening a browser as shown at this blog post .Silverlight is awesome and silverlight apps even run on MACs and Linux(limited support)
However, it is not true that Microsoft is only investing in silverlight. Microsoft is investing in WPF too. Though it is possible to create out of browser applications with silverlight, they have lot of limitations when compared to a full blown WPF applications.Dont forget that silverlight is just a subset of WPF, for example, silverlight doesnt have ADO.NET, Hardware device access etc. So if your application is merely a business application and you dont have to access hardware devices or database directly then silverlight might be an option, however if your application accessing client machines hardware resources directly then you are better off with WPF.
My suggestion is, If you know before hand that it is going to be a desktop application then go with WPF(or may be even XBAP). In my experience, useful applications grow with time, new features are always requested time to time. If in future,a feature is requested that cannot be accomplished with silverlight and can only be accomplished with WPF, then you will be in a big trouble because you need to rewrite your app in WPF and it will be hard for you to convince your CFO to allocate more fund just to implement one feature. Silverlight is not designed to develop desktop applications, its main goal is multi-platform support.
Silverlight 3 supports Out-of-Browser functionality.
Quote from Wikipedia silverlight page :
Silverlight 3 supports Out-of-Browser experiences, i.e., Silverlight applications can be installed to the system for offline access (provided the application manifest is designed to allow local installation) where they run outside the browser.
Also here is a quick howto
Out of browser applications have the same security restrictions as in browser applications.
With Silverlight 4 you can create full trust applications which have full access to the computer.
More on Network Security Access Restrictions in Silverlight
If you mean Out of Browser apps, certainly. The Seesmic Desktop 2 app is an excellent example of one of these apps, with it's own updating mechanism. Seems a no brainer to use the XAP/MEF plug-in Model and Silverlight in this manner.
Seesmic Desktop 2
We're developing an OOB app along the same lines, one internet download and you're done. You're not going to get exactly the same APIs as you get in WPF, though.
As others have pointed out, Silverlight apps can be installed to run 'out-of-browser', but even with elevated trust they still have significant restrictions on what they can do and certainly don't have "full access to the computer".
Creating an app from scratch, you may want to consider parallel Silverlight & WPF builds. The code can more-or-less be shared by adding the .cs files from one project (e.g. WPF) to the other (Silverlight) using "Add As Link". The XAML files cannot be linked this way and need to be duplicated, but that may not involve much more than copying & pasting, depending on your structure. There're good examples of this on the web.
Developing both types in parallel would likely involve a lot less effort than having to abruptly switch types at some point and discovering incompatibilities/limitations too late.
Can I use Silverlight to build cross-platform desktop widgets?
Silverlight Vs WPF
First of all, WPF is not exactly Silverlight. They essentially require different run times. Silverlight Runtime is a subset of .NET, and needs to be installed by the client, to view your SL applications over a browser. Presently SL runtime is available for Windows and Mac. Moonlight is still not full fledged, and is evolving, for Linux.
WPF, on the other hand, is purely on top of .NET runtime, and is available only for Windows.
You can use XAML to develop user experiences in Silverlight and WPF, and as long as you stick to the Silverlight subset, you can compile your XAML in WPF as well.
Desktop Widgets
Now, your thought about building cross platform 'desktop' widgets - Do you want to host a Silverlight application in a desktop window? Silverlight 3.0 provides support for hosting silverlight controls out of the browser.
Otherwise, see my blog entry on hosting Silverlight using a browser shell. http://amazedsaint.blogspot.com/2008/12/thinking-outside-silverlight-sandbox.html.
This post is revolved around
Hosting the HTML Page with Silverlight
in a Winforms/Webkit desktop application
using a web browser control, and
communicate to and fro using HTML
DOM
Embedding a light weight web server
with in the Host application, and
handle requests to perform such
operations
But remember - it is not WPF. Hope this clarifies.
In Silverlight 2.0, you won't have any such luck.
In Silverlight 3.0 (currently in beta), however, support has been added for Out of Browser Capabilities, which means you can download and run Silverlight apps from your desktop.
The Silverlight platform in general is cross-platform, so external (desktop) aplications in Silverlight 3.0 will be exactly the same.
Quoted from the What’s New in Silverlight 3 Beta? section of the release page:
Out of Browser Capabilities. The new out of browser experience in
Silverlight 3 enables users to place
their favorite Silverlight
applications directly onto their PC
and Mac, with links on the desktop and
start menu—all without the need to
download an additional runtime or
browser plug-in. Further, the new
experience enables Silverlight
applications to work whether the
computer is connected to the Internet
or not—a radical improvement to the
traditional Web experience. Features
include:
Life outside the browser. Silverlight applications can now be
installed to and run from the desktop
as lightweight web companions. Thus,
users can take their favorite Web
applications with them, regardless of
whether they are connected to the
Internet or not.
Desktop shortcuts and start menu support. Silverlight applications can
be stored on any PC or Mac computer’s
desktop with links in the start menu
and applications folder, and so are
available with one-click access.
Safe and secure. Leveraging the security features of the .NET
Framework, Silverlight applications
run inside a secure sandbox with
persistent isolated storage. These
applications have most of the same
security restrictions as traditional
web apps and so can be trusted without
security warnings or prompts,
minimizing user interruptions.
Smooth installation. Because Silverlight applications are stored in
a local cache and do not require extra
privileges to run, the installation
process is quick and efficient.
Auto-update. Upon launch, Silverlight applications can check for
new versions on the server, and
automatically update if one is found.
Internet connectivity detection. Silverlight applications can now
detect whether they have Internet
connectivity and can react
intelligently including caching a
users’ data until their connection is
restored.
I'm trying to get my head around the many application deployment options which Microsoft currently offers.
Doing a little research turned up dozens of confusing terms:
"WPF App"
"ClickOnce App"
"WPF ClickOnce App"
"MSI App"
"XBAP App"
"XBAP App deployed with ClickOnce"
"Installed ClickOnce App"
"WPF Web App"
"ASP.NET Web App"
"ASP.NET MVC Web App"
"Silverlight App"
"Full WPF App"
"ClickOnce with sync framework support"
I cleaned up my findings into seven separate approaches below. Would appreciate feedback:
"WPF App deployed with MSI" (allows lots of installation options)
MSI runtime required on target computer
wizard with options
can specify per-user or per-machine
can modify files and registry on target computer, limited only by access permission set by administrator
can place shortcut on desktop
replacing system files, etc. makes it easy to get into DLL hell on the target computer
updating is a big negative: detecting available updates requires additional tools / custom programming, not built in
user does not have to be online to use application
"WPF App deployed with ClickOnce": (good if you want automatic update but runs in sandbox)
requires two clicks (click hyperlink, click yes), no user input
only for current user, no per-machine installations
no shortcuts on desktop
appears in program list like normal applications
applications files are always copied to ../My Documents/My Applications
a shortcut to your application will be put in Start menu / your company name
cannot modify the target computer, isolated from operating system
automatically detects and updates a newer version
published simply by putting them on a webserver (where clients detect and get them)
requires .NET 2.0 or later
comparable to Java Web Start
solves four problems: (1) easy deployment, (2) easy updating, (3) low-impact on target computer, (4) no need for administrator permissions.
considered "low impact"
if two users have the same ClickOnce application installed on the same machine, they will not break each other
employs CAS for security
user does not have to be online to use application
standalone ClickOnce apps do not work on Firefox and Mac with Firefox now since it needs the .NET runtime
restricted to single-window apps since they run in the browser
building a ClickOnce manifest is much easier than Silverlight etc, since the IDE will do almost all of it for you; you just have to host the files somewhere (could be a web URL; could be a network UNC).
"XBAP App": xcopy deployment of .xbap file, IE and Firefox display it instantly like a web page
the real goal of the XBAP model is to create a WPF equivalent to the traditional HTML-and-JavaScript website (or Flash applet)
the target computer simply runs the application without installation over the web in their web browser (IE or Firefox)
They're good for Intranet applications where you want really easy deployment, the complete .NET Framework (as opposed to Silverlight) and a browser's navigational model.
99% WPF features (as opposed to Silverlight's subset of WPF features)
CAN be automatically deployed via ClickOnce as well but XCOPY is more common
YourApp.xbap is really a ClickOnce deployment manifest
run in sandbox
user must be online to use application
these must be "page-based" applications as opposed to "windows-based" applications
"An XBAP appears to run inside the brwoser simply because it displays all its content in the browser window. This is different from the model used by ActiveX controls (and Silverlight), which are loaded inside the browser process."
XBAPs offers a "prompt-free" experience, as long as .NET 3.5 is installed, it just shows up in the browser like a web page.s
XBAPs are not allowed to use WinForm controls via Interop
not allow to use windows drag and drop
most advanced WCF features are NOT allowed and XBAP can't communicate with any server other than the one where the XBAP is hosted
"if your application requires full trust, you should consider building a stand-alone WPF app and deploying it using ClickOnce" (Pro WPF in C# 2008)
trick: you can embed multiple xbap applications into multiple iframes on one HTML page.
"Silverlight App": runs in client's browser and uses downloaded 4MB subset of .NET framework, i.e. no 3D)
cross browser (applications can be used by Opera and Safari as well)
updating application is as easy as with ClickOnce or XBAP
single window apps
application is in the sandbox of course
async only
"ASP.NET MVC with JQuery/AJAX": a new development platform equal to development in WPF in terms of RAD and TDD
this approach is worth considering along with the WPF/Silverlight approaches
"ASP.NET App": classic web application with ViewState, etc. probably will be used less and less as ASP.NET MVC gains acceptance
"WinForm App": classic windows application, will be used less and less as WPF gains acceptance
I would particularly appreciate feedback on:
how reusable are controls (e.g. if we develop in Silverlight, can we reuse our code/controls in XBAP?)
what is the best approach to clients which are sometimes offline, sometimes online AND need access to WCF (probably clickOnce apps I would think)
Great Summary, Edward.
Much of the code in Silverlight can be directly used in WPF & WPF XBAP apps because Silverlight is a subset of WPF. For XAML, you will have to change the namespace URI and probably have to do some slight manual tweaking.
For XAML to Silverlight conversions, you will have to do change the namespace URI as well but refactoring might be necessary if WPF elements are used that are not in Silverlight.
WPF and the Sync Framework are great options for online/offline applications. See the Syndicated Client Experience Starter Kit for an example of a WPF/Sync Framework app. Also Silverlight + Windows Live Mesh will provide online/offline capabilities.
AppStart experience:
MSI =
Only Windows. Many clicks. Install before use. Good for very huge and resource intensive apps. App can be distributed on dvd. App can do everything. No technology restrictions.
ClickOnce =
Only Windows. Can be activated from webpage. Is downloaded once. Keeps info abouts it origin (Server) and can automatically update. App is restricted. Needs .NET
Silverlight =
Runs on Windows/Max/Linux(soon) and future Mobiles(planned). Is a webpage or can be embedded into html. Code is on Server and will never be installed. Needs Silverligth-Runtime. Provides subset of WPF
XBAP = Like silverlight but only for windows. Nobody will need that. Silverlight is better
Programming technology:
Silverlight =
Runs on client maschine. Uses WPF*
ASP.NET =
Runs on server maschine in .NET but Javascript/html on client maschine.
WinForms = old technology
WCF = won't work for browser based apps. Is for distributed apps. One could open up all doors into client mashine. Using WCF = needs MSI.
WCF provides a good framework for server. You will never need WCF on client when you use REST for interfacing. The client can be connected/disconnected in ClickOnce and MSI installed apps. You have to connect to a webpage for appstart in silverlight and ASP.
XAML can be reused for silverlight/wpf/xbap. Minor changes in wpf/silverlight. No changes in wpf/xbap as I know.
The deployment options MS supports for client applications are
MSI (Any Windows app)
Clickonce (only for .Net client apps)
Clickonce is not WPF specific.
XBAPS are clickonce deployed, browser hosted WPF apps in a trusted security sandbox.
WinForms apps can be clickonce deployed and can be browser hosted.
Silverlight is (mostly) source compatible with WPF. You can recompile SL controls as WPF controls.
Non browser hosted clickonce is probably a good fit for you.
I wouldn't be so quick to dismiss XBAP as "Silverlight for Windows only". Because it uses the complete WPF set, it is possible to use the same codebase for both a WPF App and an XBAP, as long as you work within the Partial Trust restrictions imposed on XBAPs.
Also, as of .NET 3.5, WCF does work in XBAPs under Partial Trust. You can't do as much as in a full trust WPF App, but it is still useful.
You listed "MSI App". Windows Installer is Microsoft's technology for installing and upgrading programs on Windows. The installation packages it creates have the ".msi" extension. (It was originally going to be called "Microsoft Installer". They changed it to "Windows Installer", but keep the extension.) It defines a standard way to create install packages. Packages can be created by many different tools (InstallShield, WiX, Visual Studio, etc). It's not limited to WPF apps. You can use it to install almost any kind of application.
Another deployment option made available by the Live Framework (Live Mesh vNext) is the Mesh-Enabled Web Application (MEWA). This lets you package up Silverlight, DHTML, and Flash apps to run online in the Live Desktop or online/offline on the Windows desktop. You can install a MEWA into your Mesh and have it automatically deployed to all the devices in your Mesh. If a new version of an app is released, the update can be synchronized to all devices as well.
There are hints that in addition to Silverlight/DHTML/Flash, future versions of Live Framework will support MSI and CAB packaged apps, presumably with similar deployment features.
Documentation for Mesh-Enabled Web Apps:
http://msdn.microsoft.com/en-us/library/dd199554.aspx