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Programmatically scrolling to a particular item in a ListView has become absurdly easy in WPF. However, it seems that this is not a well-known feature. I've had a number of people ask me about how to do this and if you google on "wpf ScrollIntoView" you will find almost nothing. All you need to do is get a reference to the item you are trying to scroll to and call the ScrollIntoView method, like so:

Easy, eh? To demonstrate the functionality, I've included this cheezy XBAP example...

Apologies for the lack of recent posts. Things have been hectic with a wedding (not mine) in Hawaii recently and preparing for a trip to Italy next week. Have no fear, though--there are lots of interesting things coming up!

 -Michael G. Emmons

Here are the project files for the SmileyButton WPF example. Enjoy!

 If you have any problems with this or any of my other WPF examples, drop me a line.

-Michael G. Emmons

I have been made aware that the xbap examples are not being served up correctly. I am looking into this and should have it resolved soon.

[UPDATE] It seems that the MIME types required to serve the XBAP did not register right away, even though they were added to the configuration files. Everything should work correctly now.

If anyone has any other issues please let me know.

-MGE

Here is the XAML source code for the SmileyButton control templating xbap example which I showed in my previous post.

A few weeks ago there was a good humored Channel 9 video named "Reskin Your Application with the KevinButton". While the video is lighthearted, it makes a very important point: Control templates are one of the most powerful and important reasons why we should all look at WPF as our future development platform. I've had discussions with many people who are just starting to look seriously at WPF. Their initial response to the new platform is very similar and can be summed up by, "WPF has some cool features and nice eye-candy, but I don't find it particularly ground-breaking." Invariably these same people completely reconsider their initial impressions once they "get" what control templates are all about.

To get an understanding of exactly why control templates are so powerful you need to know that, with a very few exceptions, in WPF controls do not own their presentation. The presentation of a control is almost completely separated from the business logic of that control. By using a control template the presentation can be overridden to be almost anything.

In the Channel 9 video, Kevin Moore and Robby Ingebretsen create a new button template that animates a button using a grid, some rectangles and a few images. Check out the video. I was unable to find the source code for their example so I quickly created a similar SmileyButton xbap example for everyone to peruse. Just click on the picture below to run the xbap app. This does exactly the same thing as the KevinButton, but using different images. The smiley will animate according to which part of the button the mouse is over. This has been built using the July CTP.

If you haven't had a chance to watch the video, the important thing to note about this example is that the single control in the application is a button: it captures and hooks into all the events and methods that a standard button inherits. It just has its presentation changed to be something other than the default.

The xaml source code for this WPF example can be found in the next post.

I still see lots of questions on how to make a main application window transparent or semi-transparent. This was a bit involved in versions of WPF previous to the June CTP and was not very practical because it could not be rendered in hardware. But functionality added to WPF since has made it easy to accomplish and it supports hardware rendering when available. All you need to do is to base your main scene on the Window class and add the following code to the constructor:

this.WindowStyle = WindowStyle.None;
this.AllowsTransparency = true;
this.Background = new SolidColorBrush(System.Windows.Media.Color.FromArgb(0, 34, 34, 34));

Note that the amount of transparency, or more correctly, opaqueness, is set by the alpha channel which is the first number in the FromArgb method. Setting the alpha channel to 1.0 would be 100% opaque. 0 is 0% opaque and .5 is 50% opaque.

-MGE

I am currently looking at ideas for how text can be incorporated into an application in interesting ways by incorporating 3D surfaces. My proof-of-concept will be an xbap application which gives a hands-on review of the features of the Nokia N80 phone. My initial idea is to have a 3D representation of the phone which can be rotated. As the point-of-view of the phone changes documents related to the currently viewed face of the phone will rotate onto the viewing surface.

This is currently in the planning stages; I should have something to show in the next few days.

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Here is the source code for the PostIt Board WPF Example. This was compiled under the July CTP of WPF. The Visual Studio 2005 solution file was built with the June CTP of Orcas. Feel free to drop me a line if you have any questions or comments.

In my previous post I promised I'd get you a working copy of the example app. It can be found here. This is just the executable as I am cleaning up the code for the project to make it somewhat more presentable. This demo is made for the July CTP of .NET Framework 3.0. Above you can see a screenshot of the example with around 80 pics sitting on the corkboard...click the pic for a larger version.

You may notice that the details postit is no longer skewed as it was before. This is because there doesn't seem to be a way to base the orientation of the InkCanvas recogition to the application window. Instead it attempts to recognize gestures in whichever�orientation it happens to be in. This is a good thing, in general, but for this example it made recognition rather difficult since you are forced to skew your gestures to match the skew of the PostIt. Probably not a big deal with a TabletPC and a stylus, but a pain with a mouse.

It will run on Windows XP, but unless you have the Microsoft Windows XP Tablet PC Edition 2005 Recognizer Pack it won't recognize any gestures (note: this can be installed on any XP operating system, not just the Tablet PC edition). Recognition is built-in to Widows Vista.

Sorry folks, no XBAP edition of this app. Although I generally want to release an XBAP version of each bit so you can see it online without having to download it, getting a browser enabled version of this one up-and-running would be more trouble than it's worth.

-MGE