for my final project in university i am developing in asp.net mvc3 and using silverlight for vector graphics.
I store silverlight code as string/xml in a database, and i want the ability to manipulate it dynamically (change proportions etc..) and display it in my aspx view. i don't want and can't use files because of scalability issues (there will be a lot of them) and because of possible porting of the application to the cloud (Azure).
basically i want to build a controller that will take raw xaml code from the DB and display it. all the solutions i found on the web are about two options which is not helpful for me:
http://msdn.microsoft.com/en-us/library/cc189044(VS.95).aspx - which involves manually creating the entire dom object and integrating it in an existing silverlight page, which i don't have
http://visualstudiomagazine.com/articles/2008/01/21/using-inline-xaml-with-silverlight-listing-2.aspx - using embedded header in the html itself - again not pracrtical..
maybe someone can suggest me a practical solution for my problem
I would suggest the you spend sometime examining in detail how the Silverlight navigation framework can be used.
I'm think you should be able to use the Frame element with your own implementation of INavigationContentLoader assigned to its ContentLoader property and possibly your own derivative to UriMapperBase assigned to its UriMapper property.
You would then use a URL like this:-
http://yoursite.com/yourHostController#/yourXamlController/someReference
You would have two views, "yourHost" would simply generate the HTML nececessary to host the Silverlight application you will build. The "yourXaml" view would simply serve up the raw Xaml.
Your Uri mapper will take the relative url supplied after the # (this is how silverlight intra-application navigation works) and create a Uri that can points at yourXaml controller.
Your implementation of INavigationContentLoader will then fetch the Xaml from the Uri and load it up.
Assuming the Xaml contains hyperlinks to using urls like "/yourXamlController/otherReference". You should be able to navigate around your stored Xaml without reloading the Silverlight app. Everything will be about referencing and downloading new chunks of Xaml.
Related
I'm trying to figure out what would be best solution to the problem I'm facing. I have a Silverlight application which should be composed from different modules. I can use Prism, place regions and load modules and fill regions with loaded modules but this is not enough in my situation. Here's what I want to accomplish:
For most views that gets loaded from different xap files, I should place an element somewhere in the shell, which will perform navigation to the dynamically loaded view.
That element (which links to dynamically loaded view) should support localization and should have dynamically assignable data templates, different module links should have different content/data template (I'm thinking writing data templates in xaml files on the server and reading them from silverlight via XamlReader, maybe there's a better way?).
Uri mapping and browser journal should work with navigation. Silverlight default navigation mechanism better suits my needs than the one found in Prism.
The architecture should support MVVM.
I think thats all. I just couldn't think of a good architecture which will satisfy all my needs. Any help would be greatly appreciated.
I do not know of a single product/solution that would cover all your requirements, so here are some comments on each:
If one area of the shell has a region that supports multiple items, you just register a control of type link/button etc with the same region name in each module. For example we register views based on the Telerik TadRibbonTab (instead of UserControl) with a region named "views" which is a RibbonBarTab with a region named "views". Every module then adds its its own button to the list. You can do the same thing with any multi-item container.
Localisation is a completely different issue and can be solved in a number of ways. See my answer here: Load Resources ".resx" from folder in Silverlight
A custom navigation mapper can be made to behave like the standard one, without messing up the support for Prism regions. The one we created encodes GUI information such as current selections (current view and item selections etc) into the URL. That means we are in total control of the state and the URL controls the state.
Hardly anything stops you using MVVM as that is one small feature for separating views from code-behind data.
I will be interested in what other solutions are proposed as we are always looking for new ideas too.
I come from mainly a web development background (ASP.NET, ASP.NET MVC, XHTML, CSS etc) but have been tasked with creating/designing a Silverlight application. The application is utilising Bing Maps control for Silverlight, this will be contained in a user control and will be the 'main' screen in the system.
There will be numerous other user controls on the form that will be used to choose/filter/sort/order the data on the map. I think of it like Visual Studio: the Bing Maps will be like the code editor window and the other controls will be like Solutions Explorer, Find Results etc. (although a lot less of them!)
I have read up and I'm comfortable with the data side (RIA-Services) of the application. I've (kinda) got my head around databinding and using a view model to present data and keep the code behind file lite.
What I do need some help on is UI design/navigation framework, specifically 2 aspects:
How do I best implement a fluid design so that the various user controls which filter the map data can be resized/pinned/unpinned (for example, like the Solution Explorer in VS)? I made a test using a Grid with a GridSplitter control, is this the best way? Would it be best to create a Grid/Gridsplitter with Navigation Frames inside the grid to load the content?
Since I have multiple user controls that basically use the same set of data, should I set the dataContext at the highest possible level (e.g. if using a grid with multiple frames, at the Grid level?).
Any help, tips, links etc. will be very much appreciated!
Microsoft has created a great community site for helping people get started with both design and Silverlight here: http://www.microsoft.com/design/toolbox/
It may be far more than what you need for your current project, but it definitely will give you the training you need to master Design with Silverlight.
So far I have been creating Silverlight apps with all logic crunched into a single xap file. But as the application grows in size,
I seriously think I should break my Silverlight application into smaller multiple independent applications.
I would like to know how others solve this increasing size problem??
If you're looking to make some changes to your application, by refactoring it and splitting out parts, consider all of these.
Custom controls get their own control assembly
Definitely create control assemblies for any custom controls you develop. Not only do you get the benefit of self-contained controls, and optional use in your current and future projects, you can
take advantage of default control styles
use the cached assembly feature with them
share components with other projects
invest in your core code and controls, instead of investing in cleaning up application logic (if you're using static or style analysis, for instance) - spend your time where it will make the most impact
Consider dynamically loading new assemblies
There are some methods available for dynamically loading additional code into your app domain, it may be possible to abstract out less-often used parts of your app, and use this to load in those components. This is a more complex and involved app, but it can improve start-up performance.
It'll take time to split out the code into other assemblies when you're looking at a large application, and testing it can be a challenge. But you can end up with "sub-pages" and parts of your app being loaded only as needed.
Taking the time to design a system to load in new functionality and parts of your app, and architecting this framework, can take time to do right. This typically is using AssemblyPart to load a new assembly that you can reflect into and instantiate new objects from.
Merged Resource Dictionaries
Resource dictionaries can allow you to store styles, control templates, and other resources outside of pages, and outside of your App.xaml.
Cached Assemblies
Once you move to Silverlight 3, you can use the cached assemblies feature to store individual assemblies outside your .Xap, alongside, on your server - and as a bonus, those assemblies will be cached on the machine for quite some time.
A resource diet
Are you really using all of your graphic assets, XAML, controls, string resources, etc., that are stored inside your XAP file? Audit it from time-to-time and make sure you're getting the most bang for your byte.
A splash screen
If you're simply trying to improve the performance (download time) for your application initially, consider creating a splash screen. The Silverlight Toolkit samples have one - it's a simple Silverlight page that will load and display while your .Xap downloads.
Remote graphics
Instead of including image resources right inside your application/XAP, move your images to your CDN or server, so they can be loaded only as needed. This is often a nice and quick win.
Simplify your app
Make sure you actually need it to be XAML-heavy, graphic-heavy, etc. Maybe it can be simplified!
You should distribute your Silverlight modules using PRISM or MEF frameworks.
Visit http://mef.codeplex.com/
I've got a single Silverlight app that I'd like to display in a grid. The way the Silverlight app displays its content is dependent on the unique ID of the record in each grid row. Unfortunately, the XAP file is re-downloaded for each row in the grid. With a size of 700KB, this really impacts performance. Is it possible to download the XAP file once and then just re-use it for each row in the grid?
Once a XAP is downloaded Silverlight will cache the assemblies etc locally per instance of a Silverlight control. If you create another instance of a Silverlight control then this in turn has it's own domain that it in turn looks after.
My suggestion is to abstract out the parts you requrie and bake them into a seperate xaml, then load them into areas where you need them the most. If you still require a central .xap to handle the marshalling / event management etc then in Silverlight 3 we've put in place a Local Connection API which allows other Silverlight instances to talk to one another within the one browser page locally (ie SilverlighA can talk to SilverlightB all within index.html)
This can then allow you to establish a sort of local proxy if you will.
Scott Barnes / Rich Platforms Product Manager / Microsoft.
I'm not sure you can. Theoretically it should be cached, but in this case theory don't seem worth squat.
It's all down to the way the < object > tag behaves with it's various params and this is (another) one of the "sparsely" documented areas of silverlight.
It is possible but not easy to do. You could download the xap and save it to IsolatedStorage and create a silverlight host each time you need one referencing your cached xap but you only have 1MB space available and you aren't guaranteed that if you have other silverlight apps from the same domain.
Given what you described I still don't see any value in doing what you want to do. I think you have it backwards.
I want to know about general methods to dynamically load content into your silverlight application.
More specifically, I want to create something like a widget-based application, where all GUI objects are small independent widgets. I want to provide a static chrome, like a frame, hosting the actual widget, that is loaded from an extern source like a website or is uploaded by the user and is shown in this frame.
The questions are:
What does the widget author specifically have to provide, in order for me to load his widget application into my application? I imagine I have to query the provided DLL for something like a ViewModel and its DataTemplate, a UserControl or even a XAP File. What would be the best way? The external widget should also implement a certain interface, so that the outer application can call methods like Loaded and Unloaded on it.
Small code samples would be appreciated.
What about security? How do I prevent the inner widget application to access my outer application. I think the widget app could go up the control tree or access the DataContext of my frame control, hosting the application. Is this an issue? If so, how to solve it?
Thanks in advance!
Andrej
You can dynamically load controls from dlls that your widget authors could provide, MS's Mike Taulty's done a walkthrough.
Microsoft also have Prism which allows you to break up your silverlight code in a modular fashion. I haven't tried it yet to see if it's suitable for loading individual controls, but my impressions of what I've read about it seem to indicate it has a framework for doing that.
As for security, they would have access to the rest of the application, so perhaps this isn't suitable.