Gizmox - Guy Peled's Blog

Wiktor Zychla has assembled a tiny AJAX framework contest between Visaul WebGui, ASP.NET AJAX and Ajaxium. Comparing a givven scenario he checked bandwidth consumption, requests per second, etc. The results as Wiktor wrote them are: "The VWG is an undoubt winner. It did a great job of serving the highest number of requests per second, 422, and is also a clear winner regarding the amount of data sent to and from the server."

Contest context

More than two years ago we've built a small web application used to collect and print documents required to participate in secondary school final examinations in Poland. The application is used quite extensively by people from all over the country.

The application, maturzysta.vulcan.pl, is located here.

From the web developer's point of view there is one interesting aspect of the main form of the application: there are about 30 dropdown lists with complicated logic between their selections: when you change the selection in one list, few others should be cleared or repopulated with context-bound data. There is also quite a lot of validation of various dependencies between user's selections.

The first version of the application was built as a server-side application: all SelectedIndexChanged events were auto-postbacked and processed on the application server. This caused a lot of trouble since the heavy form had to be sent to and fro the server.

The year later we've completely redesigned the application, moving the interface logic to the javascript. The web traffic problem has been solved but two other appear. First of all - no one likes javascript, it's clumsy and error-prone. Then - we had to disable ASP.NET page validation mechanism because otherwise the page content modified on the client-side would be rejected on the server-side as potentially dangerous.

In the meantime, few promising AJAX frameworks appeared and we thought that it would be possible to go back to the initial version of the application but instead of expensive postbacks we could take the AJAX approach and replace postbacks with callbacks. This could solve all problems: reduce the traffic and still keep the application logic on the server-side.

Read more...

A new version has been released and it includes many bug fixes and lots missing functionality implementation mainly with in the DataGridView control. There are also lots of new features that had been requested by developers including redirecting, clipboard support, Invoking client side scripts, Calendar first day support, ListView auto resize and more.

The DataGridView control has been added many missing implementations including selection management and events, deleting rows, resizing columns and rows, changing captions and visibility, alternative row style and more. You should be aware that previous versions of VWG had added the DataGridView control with lots of unnecessary definitions. While not harmful in the previous version, in the new one those different properties are working and could cause unwanted behaviors. You should clean up the InitializeComponent code from the different DataGridView definitions keeping only the positioning,dimensioning and data source attributes.

We are currently also working on a Vista theme that will be released soon. The site demo has already updated to work with the new theme.

For a more detailed change see the issue tracker here.

As always you can download the latest version from here.

Yes I know I have not written for a long time.  I was kind of thinking about blogging and all and I did not get my self to start writing. Any way there is a new Visual WebGui version with extensibility features and we are working on supplying at last documentation. God knows way but documentation seems to be the hardest part of the development process and yes we all know its a very important part of any product.  Documentation is on the way....

As always you can find the new version here: http://sourceforge.net/projects/visualwebgui.

The new version contains many bug fixes and performance enhancements and the change log can be viewed at http://support.visualwebgui.com.

As always you can find the new version here: http://sourceforge.net/projects/visualwebgui.

There is a new version fixing a critical bug found in the last version regarding a new capability for boosting performance by caching resources in run time. The bug caused an error to be thrown when the application was executed which detailed a permission denied error on writing a file to the “C:\windows\system32“. Just to clear things up, Visual WebGui does not require these permissions and normally it does not attempt to write the disk. 

In order to test the new performance boosting capability a definition should be added to the WebGUI section:

<StaticResources Mode="On" />

There could be some permission issues with this feature as it uses a physical directory to store cache. You should add a "Route" directory under the site root and give it write permissions to avoid permission issues.

There is also a new Timer component that basically works just as the WinForms timer works. It is new feature that is still under QA. It is critical that you call Timer.Stop() or Timer.Enabled=false before the containing component dies as currently timers are not destroyed automaticly. Timers don't work currently by default and should be enabled by adding a definition to the WebGUI section:

<TimersEnabled Mode="On"/>

When this feature is released this definition will not be nacecery.

There is also a new configuration key called PrivateVersion that allows developers to add custom cache version dependency. The private version is concated to the public version cache key and enables invalidation of cache in cases like theme development or custom controls. The cache key is used both client side and server side so by changing the private version you actually are invalidating also all client cache. The private cache is used as following in the WebGUI section:

<PrivateVersion Value="2"/>

If the current public cache version is "1.24" the cache key will be "1.24.1".

As always you can find the new version here: http://sourceforge.net/projects/visualwebgui.

In my opinion the last two versions of Visual WebGui including this one shows why it's a killer environment. When building super complex apps comes to dragging three components to a design surface and writing a few lines of code to bind them together this sounds like a RAD product. But Visual WebGui does not assume what you want to do. It just takes care of the “how” and leaves you only with the “what”. You see I have recently learned that modeless dialogs in IE are working as a separate thread and therefore you can not work properly with an XMLHTTP object that was not created by the modeless window. How much time would you burn figuring this out. Well who gives a dam it is already part of the internals of Visual WebGui.

Any way take for example this app here (You can click the image to enlarge):

You have a ScheduleBox control which is a new Visual WebGui control working with a DataGridView which is also a new addition to the Visual WebGui environment and you have a PropertyGrid that enables you to change the current displayed date and view and so on.... Definitely not something you would normally encounter when browsing to a URL that does not install anything. You have a fully working DataGridView binded to the events collection of the ScheduleBox control. Every change you do in the DataGridView will automatically reflect in the ScheduleBox in the middle. Say you change the subject of an event or the duration it will automatically update in a friction of a second sending no more then 1KB and receiving no more the 1KB updating the view to reflect exactly your change.

You have the PropertyGrid which is binded to editing the ScheduleBox control just by assigning the SelectedObject property of the PropertyGrid the reference to the ScheduleBox control. Immediately you get full control over the ScheduleBox you can apply border you can change its current displayed date and you can change its view.

Would you believe that all this can be done with this code:

Well I love it, no scripts, no HTML, no pages, no requests, no XML just plain old read it and execute OOP code. I guess I sound kind of excited, drunk on my own alcohol, but for me it is a dream come true. I remember days when I was coding tones of JavaScript lines thinking that there most be another way.

Well mark my words, these days are over.

Any way as always you can find the new version here: http://sourceforge.net/projects/visualwebgui.

The new version is available at source forge (http://sourceforge.net/projects/visualwebgui) and includes some new exciting features such as enhanced design time capabilities, data binding, colorlistbox control, and a new full blown property grid control.

Design time architecture was re engineered to comply to WinForms standards and now enables to create and consume custom controls and user controls as simple as the built in controls.

Data binding capabilities enables binding list boxes and combo boxes to collections and data sets enabling auto initialization and updating when the binded data updates.

The new property grid enables developers to created design oriented applications or use it for rapid data editing applications such as admin applications.

The next release of Visual WebGui will include some exciting new features that considering the amount of developers that requested these features will defiantly be some thing to look for.

We have added data binding support enabling binding of collections and datasets to list boxes and combo boxes and binding controls to a currency manager that provides synchronization between controls just as WinForms does. All the features of the data binding mechanism are available more and more controls will support data binding interactions in the next versions including the new DataGridView controls that is in work as these words are written.

Another new existing feature the next version will include is PropertyGrid support that has all the capabilities of the WinForms PropertyGrid. Most of the declarative attributes remained the same except for UI related attributes (UITypeEditor, IUIEditorService). These attributes map types to editors that can interact with the PropertyGrid through the IUIEditorService. To avoid conflict between the WinForms attributes and the Visual WebGui attributes a new attribute is introduced called WebUITypeEditor that defines how a property is edited when displayed via web while the UITypeEditor keeps on working the same way it did. From with in the WebUITypeEditor you can call GetService to retrieve the IWebUIEditorService and display a form as a dialog of a specific property or as a dropdown of a specific property. Other from these UI related issues all other attributes are applied to the Visual WebGui PropertyGrid including the type converter and all other design related attributes that developers are familiar with in WinForms. The Visual WebGui next release contains two built-in PropertyGrid editors for editing Color types and Font types the same way WinForms does while all other types are currently text based editing.

Here are some screen shots showing the new PropertyGrid:

Category sorted PropertyGrid:


Alphabetic sorted PropertyGrid:


Color type PropertyGrid editor:

This control uses a new ColorListBox control added in the new Visual WebGui release. This control has the same interface like the standard ListBox but expects its items to be typed Color. It displays its items with a color preview icon.



Font type PropertyGrid editor:

This editor uses a new dialog introduced in the next version that implements the WinForms FontDialog via Viasual WebGui. The only difference the Visual WebGui dialog has is that user response should be retrieved from a callback event handler as Visual WebGui dialogs are only modal on the client. Attaching to the closed event allows developers to check an IsCompleted property to find out if the user has completed the dialog using the OK button.

View the change log here.
Download the new version here.

Visual WebGui Enterprise Manager is available at SourceForge. The a new database administration tool was developed with Visual WebGui and is based on Microsoft's “Enterprise Manager”. Presenting a familiar interface for administrators and developers the application brings the power of the enterprise manger to the web. The application has extended the “Enterprise Manager” with a provider mechanism which will enable managing multi database types in a unified UI. The application is actually a natural evolution of the popular “ASP.NET enterprise manager” and provides the same capabilities and more but with a fully AJAX enabled UI and multiple database type capabilities. 

The application can be downloaded with full source code here: http://sourceforge.net/projects/vwg-ent-man.

Screen Shots:

Screen 1: Table properties dialog.

Screen 2: Table designer

Screen 3: Process view

Screen 4: View designer

We are currently working on the Visual WebGui support for non IE browsers and we were striving for a good site that will help us summarize it all up. I came across this great site named “Index DOT Html“. Which is definitely the most productive comparison there is on the web. Supplying a very smart navigation system you get what you need quickly and accurately.

Two thumbs up for Brian Wilson which created this site.
http://www.blooberry.com/indexdot/html/index.html