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Pre WPF days just had a Label control and hence there wasn't really a choice. Now in WPF you have Label and a new TextBlock control. I have been wondering on usually which one to use in the application when i hit upon this interesting comparison between the two by Josh. There is one additional difference mentioned in comments down below on that blog that talk about auto inversion of colors for TextBlock if it is part of say a ListItem. However to me it looked more like setting the Foreground to white, since when i tried with styling the item selection color to something else, the TextBlock still showed white color.

Honestly I am now left more confused. TextBlock is light weight and hence good from app performance perspective, but Label gives the access key functionality, something that people prefer to have in their applications. It will be really good to have this functionality extended to TextBlock.

What is it that you use in your applications and why? Comments welcome. 

Posted by Atul Gupta at 06:30 AM | Permalink | Comments (1) | TrackBacks (0)

When using object instances in XAML, there are two ways to use them. One is to directly create them as resources, assign and key and use where ever required and other is to embed them inside of ObjectDataProvider and then use.

I have worked with both ways and was curious to know the differences between the two and benefit of using one approach over another. I can across this old blog by Beatriz that explain this very well. Along same lines, here is some discussion on XmlDataProvider as well.

Posted by Atul Gupta at 04:03 AM | Permalink | Comments (0) | TrackBacks (0)

I have been playing around with WPF for a while and have been blogging about some of the technical aspects on it. However today I will like to touch upon another important aspect of WPF and that is designer-developer connect.

Having worked on Windows Programming using C++, MFC etc for a decade and working with the various controls, it is a real pleasure to see the capabilities now available to WPF developers. It is true to a large extent that with WPF and XAML and the tools like Expression Blend, designers and developers can work lot more closely than ever before. The working closely is more towards the ability for designers to style the UI for the WPF application and the developers to write the code for it.

Continue reading "WPF makes Designers and Developers friends again" »

Posted by Atul Gupta at 12:51 PM | Permalink | Comments (2) | TrackBacks (0)

There are enough online sources that talk about how to buid and use custom Converters in WPF and also how to pass parameters to these converters. However for some reason, all these examples tend to either use a single integer or a single word string. So recently when I had a need for passing a sentence as parameter, I was confused.

Fortunately the simple trick of using single quotes inside of double quotes to provide strings worked in this case as well. Following are two ways you can pass a string that has multiple words to a converter.

Continue reading "WPF - Passing string to ConverterParameter" »

Posted by Atul Gupta at 11:53 AM | Permalink | Comments (0) | TrackBacks (0)

Overtime, I have used different approaches to binding pictures to Image control in a WPF application. I have seen various questions on the WPF forum as well on this topic. The information is all available out there, but scattered. Hence, I decided to create a sample application to demostrate the various scenarios that can exist when you need to use the Image control to display pictures.

Continue reading "WPF - Binding to Image Control" »

Posted by Atul Gupta at 09:11 AM | Permalink | Comments (4) | TrackBacks (0)

Some days back i had answered a question on the WPF Forum on how to ensure that when the base XML file changes, the XmlDataProvider is udpated and hence the bound control on the UI.

The key is to set a watch on the particular XML file for changes and then update the provider appropriately. See details here. This solution works fine, but I didn't particularly like my initial code that I wrote since the FileSystemWatcher was set externally. It would be better if this could be self contained within the XmlDataProvider itself.  

Continue reading "WPF - Updating XmlDataProvider when source XML changes" »

Posted by Atul Gupta at 06:08 AM | Permalink | Comments (0) | TrackBacks (0)

Some days back I had pointed to the blog by Beatriz on how to debug WPF data binding errors. I have been using the PresentationTraceSources.TraceLevel feature (available with .NET 3.5) since then and have found it very easy to use and very effective in resolving my data binding errors.

However recently when I opened a XAML, which had this debugging feature enabled, in Expression Blend 2.5 March Preview, I got an error. The XAML won't open in designer and showed "Invalid XAML" with details as 'The member "TraceLevel" is not recognized or is not accessible'.

Continue reading "Expression Blend issue with WPF Data binding debugging" »

Posted by Atul Gupta at 03:30 AM | Permalink | Comments (0) | TrackBacks (0)

Some days back, I had blogged about this issue and suggested how to set global style to counter this. However it turns out that with that you may run into 'Cannot use UndoService while it is disabled' related error. To address that, you will need to modify the style using a DataTrigger as below.

Posted by Atul Gupta at 04:39 AM | Permalink | Comments (0) | TrackBacks (0)

Recently on the WPF Forum I came across an interesting problem about use of XmlDataProvider in XAML and its ability to load external XML files. It took a bit of a struggle, but eventually I did manage to get it working. Here I will try and explain it in some detail so that others can also benefit.

We all know that one can easily bind to inline XML in XAML or can load that from external file. If working with inline XML, you usually use XData to specify the XML file content.

Continue reading "WPF XmlDataProvider, Working with External XML Files" »

Posted by Atul Gupta at 05:00 AM | Permalink | Comments (0) | TrackBacks (0)

Last week I had blogged about an issue with Expression Blend Dec 2007 Preview when working with Globalization and Localization. Yesterday at MIX 2008 Microsoft has launched Expression Blend 2.5 March 2008 Preview along with SilverLight 2.0 Beta. For a list of all the products announced during MIX check here.

With the new version of Expression Blend available, I went ahead and upgraded my machine with it and decided to give it a shot for the Globalization issue I had faced earlier.

Continue reading "Expression Blend 2.5 still has some issues with Globalization" »

Posted by Atul Gupta at 06:14 AM | Permalink | Comments (0) | TrackBacks (0)