Following on from my previous post, where I explained how to create a ControlTemplate to style a TextBox in WPF, I’ve got an object, TextEntryBox, which dervies from a TextBox (it provides some custom event handlers when text is entered, but to all intents and purposes, it’s a regular TextBox).

I wanted to style my TextEntryBox, this time including a button within my ControlTemplate (this will eventually toggle an on-screen keyboard pop-up, but that’s another blog post!). I came up with this:

All’s well and good, until I want to try and handle the Click event for that button within my TextEntryBox class. Even Matthew MacDonald’s “Pro WPF in C# 2008″ which has proved a lifesaver for all things WPF since I’ve been working with this technology only had the following words of wisdom;

“You can’t attach event handlers in the control template. Instead, you’ll need to give your elements recognizable names and attach event handlers to them programmatically in the control constructor”

But whatever I tried I couldn’t access the event in my constructor, until I remembered the seperation between the visual and logical trees in WPF.

The template is applied at runtime, and so elements contained within it it are part of the visual tree. My class, and therefore my class’ constructor is executed within the logical tree, so I needed to attach my event handler after the template had been applied. You can do this by overriding OnApplyTemplate in your class, obtain the template that’s being applied, and then you have access to the named button’s events, like this:

public override void OnApplyTemplate()
{
    DependencyObject d = GetTemplateChild("PART_KeyboardPopupButton");
    if (d != null)
    {
        (d as Button).Click += new RoutedEventHandler(KeyboardPopupButton_Click);
    }

    base.OnApplyTemplate();
}

Note the null check, as someone could have applied a completely different template to the object.

Q: If you want to create a ControlTemplate to provide a custom style for a TextBox, how do you specify where the text goes when it’s used in WPF?

A: The answer was hidden in the depths of the MSDN Documentation. You have to include a <ScrollViewer> within your ControlTemplate with an x:Name value of “PART_ContentHost”.

Here’s a noddy example:

To celebrate 2010 in style, I’m launching a 365 Photography Project.

It’s got it’s own blog and I’ll be posting photos to my flickr stream and to the blog every day so please check it out!

First post…. tomorrow! =) Hang-over or no hang-over…..

Right, let the festivities commence!

The book covers my best shots taken between 2006-2009 and so pretty much plots the development of a serious photography addiction for me, from the early 350D days, right up to the most recent Cornwall trip and Low Light Photography Course I attended last month (yes, blog post LOOONG overdue for that one, it’s on its way. The photos are just hitting my flickr now and over the next few days!)

Photos 2006-09

A collection of my…

By Richard Dutton

Book Preview

Please feel free to drop by and have a look, all of the photos are from my flickr stream but I thought it was about time to have something in print.

Blurb’s software has come on in leaps and bounds since the last time I tried them out a few years ago. With a version for both Mac and Windows users, it provides not only the standard templated layouts, but also the ability to tweak and create your own layouts from scratch, something which I felt was missing from the original version.

I’ve got a printed copy on its way and will report back as soon as it arrives.

While Microsoft are happy modifying and ‘updating’ other people’s software in one of their updates, they then seem a bit lapse in keeping on top of the ol’ bug fixeroo, one of the primary reasons people flee from IE in the first place.

Prior to Mozilla blocking them, it turns out that this particularly nasty ‘Critical Remote Code Execution’ vulnerability applied not only to IE, but to Firefox installs containing these add-ons. So thanks guys, I’m glad someone’s watching our backs! =)

(Now, who knows what this will do to my WPF XBAP testing? After all that I might have to dust down IE!)

This was screaming out to be screen-scraped and developer Tyler Hall has stepped up to the plate with Sosumi – A MobileMe Scraper. Using Sosumi is literally a case of including the class in your PHP, instantiating it with your MobileMe username and password and calling its locate method which returns an object containing the current latitude, longitude and result accuracy, it’s as simple as that!

At the moment I’ve got a cron job on my server hitting this every five minutes and logging to a database. If the data hasn’t changed since the last logged entry, a counter is incremented and timestamp_last is set. A very simple Google Map displays these locations as points on a map but I’ve got loads of ideas of stuff to play about with, such as:

• Plot the reported accuracy of each location as a circle on the map, more Google Maps fiddling.
• Modify which points are mapped based on time and date ranges through the webpage, some PHP + AJAX experience.
• Store locations of common places I visit, then for each point logged (taking into account the accuracy range) I can programatically work out where I am.  Could then auto-generate “Richard is at work”, “Richard is at home”, etc… reports for my blog/twitter/facebook etc… =).

Bit sad I know, but it seemed too good for a total sync-monkey like myself and I’ll never pass up an opportunity, however contrived, for a PHP mash-up!

Their site in Kent is excellent. It’s only open to the general public through specialist days (photographer, wildlife experiences, etc.), through which they are funded and so it’s a lot more intimate than a zoo. The enclosures are arranged around a central grass car park, ideal as you can keep heavy kit in your car which is never too far away for a quick lens change. Having said that, I managed to spent the entire day shooting with my 70-300 IS USM, despite bringing my entire kit bag and tripod!

As the site takes part in numerous breeding projects for the cats, it’s no surprise that animal welfare is their number one priority and this is reflected in the quality of the enclosures and environments they provide. The obvious advantage for photography is that you can get right up to the enclosures and take pictures through the bars which eliminates the usual problems you get trying to photograph big cats (or any of the more dangerous animals) in zoos, where you are kept back from the enclosure by another fenced off area meaning you can’t keep the bars out of shot.

The day consisted of a group tour around the various enclosures given by one of the WHF team (and his bucket of meat =) ), being introduced to each cat in turn with lots of photograph opportunities. Wild Arena’s Janet also came along to provide valuable photography tips. Once the tour completed we were then free to roam around by ourselves and take any more shots we liked.

Overall, the whole day was excellent, both Wild Arena and WHF guides were extremely knowledgeable and friendly and made the whole day go very smoothly. I’m still trying to sort through the 600+ shots I took on the day, but as I do I’ll be posting the best to my Flickr account.

Yes, it’s pretty and yes, it makes some features almost trivial to implement but I’m struggling to find a satisfactory method for implementing any form of user authentication; a critical feature to allow you guys to log in and view your entered notes. The framework is nice, one of the most visually impressive Ajax frameworks I’ve come across but this has been my stumbling block and so I just can’t justify ploughing any more of my already scarce time into it.

So, the way forward… Well from here on in it’s going to be a clean CSS layout more akin to the DT of old but with the google map integration I’ve already developed. Managed to steal away a few hours this weekend to work on a template layout and so work on the back-end plumbing is now underway. Watch this space…

I’ve been making notes throughout the whole experience and so plan to post them shortly with the aim of helping anyone else who finds themselves in a similar situation and needs to get up to speed with Windows network driver development (NDIS 5.1). I am by no means an expert but want to share what I’ve learnt so far.