Designer WPF

These are my links for February 27th:

• Quick Tip: Expression Blend – the Hand – Long story short: press the spacebar to use the hand tool without having to choose it from the toolbar
• Silverlight Drag and Drop Manager released @ CodePlex –
• “Implementing MVVM in Silverlight” – a UI perspective – Another in my ever-growing list of MVVM posts to look at
• Hands-On Model-View-ViewModel (MVVM) for Silverlight and WPF – Another in the long list of MVVM stuff… someday I'll get around to it all
• Silverlight Patterns: Model-View-ViewModel In Silverlight 2 Apps – Shawn Wildermuth's article in MSDN magazine on Model-View-ViewModel In Silverlight 2 Apps

Due to repeated requests for the source code (and the fact that I apparently can’t brag about it on Silverlight.Net without a link to the source code), I’m putting it up for download.

Presidential Candidate News Tracker Source Code

JSON Data File With Candidate Data (Note: Apparently, Wordpress likes to uncapitalize file names for me, you may have to re-name the file to “CandData.json” to get it to work with the app.)

Warning: This code is a disaster. I was having strange problems getting my custom controls to work and, after a couple hours fighting with it, I gave up and ended up writing the exact same layout and code for 14 separate candidates. Same problem with the “dates-of-note” along the timeline.

Not pretty, but it works. Have fun.

It’s not set in stone, but Brian Peek is trying to see if anyone who has played around with homebrew Wiimote projects and is also going to MIX is interested in having a get together.

If this describes you, please take his poll so he knows there is interest. (I’m voting for Wednesday, since I’m not going to be able to make it on Thursday). This is really a selfish plea on my part, since I’d love to meet so many of the great minds behind the Coding4Fun site and the Wiimote projects.

In this post, you’ll either need to walk through this tutorial on how to call and prepare JSON data gathered from the New York Times API or, if you’re not particularly interested in doing that, you can just download the final project here. This tutorial pretty much assumes that you’re starting from the end of that tutorial.

Fortunately for everyone involved (especially me), this tutorial is much shorter. It is also another in my “without a line of code” series in which you can do everything without even touching the code. Let’s open up our project in Blend and get started. (To see an example what this tutorial makes, scroll to the bottom of this post.)

First of all, I lied. You do have to touch one line of code because you need to get your NYT API key and plug it into the myApiKey variable in the Page constructor (line 26 in the project available for download). The line should look like this:

myApiKey = “&api-key=your_api_key_here”;

Now, right click on the project solution and select “Build Solution” (in Visual Studio or Blend, it doesn’t matter).

This should build the assemblies so that Blend can do a really neat trick. In the Project tab in Blend, you should see a Data panel in the bottom half. Click on the “+ CLR Object” button.

A pop-up will gently encourage you to name your new data source and choose from a list of available data sources. Select “NYTResult” and hit OK.

You will now have your NYTResult data source show up in your Data pane. Before we start building a nice slick looking interface, select your ListBox (named “ResultsDisplay”) and, in the Properties pane, find the “Display Member Path” and reset it by clicking on the little gray box to the right.

Now, right-click on the ListBox  in your “Objects and Timeline” panel and select “Bind ItemsSource to Data…”

Select the data source you just created and select “NYTResult”. Then click on “Define DataTemplate” at the bottom. This will take you to the “Create Data Template” panel, where the fun happens. You will see “New Data Template and Display Fields” automatically selected. We like this. This lets us select all the data we want and give it some basic structure and Blend will do all the bindings for us.

Let’s make a few changes from the standard Data Template setup. Expand the Date field and check Day, DayOfWeek, Month, and Year and change the order with the up and down buttons to something you like. Then, change the Url from “StackPanel” to “TextBlock”. I reordered the data a little bit, so my template looks like this:

Hit OK. The point of that whole exercise was so that Blend would build our data template for us. We don’t actually want the data source and we don’t want our ListBox bound to it. So reset the “ItemSource” property on the ListBox and remove the NYTResult data source. If you run the project now, you should get something like this:

At least we’re getting more data now. Doesn’t look that great, but we’re getting there. Go back to your project in Blend and right-click on your ListBox and go to “Edit Other Templates –> Edit Generated Items (ItemTemplate) –> Edit Template”

We’re now in the DataTemplate but we sadly have no visible data, which makes manipulating it a tad difficult. What I have found works best for me is just to build my desired layout with static data and then translate the bindings. (I haven’t mentioned this, but you should be working in Split mode as a general rule, so you should be able to see the bindings in the XAML.)

So… long story short (it’s getting really late here): I changed the layout to replicate the NYT story design… the Title is a hyperlink button that takes us to the full story, followed by a small byline, the beginning of the story and the date on which the story appeared. If you’d like to look at the design itself in more detail, download the project at the end of this post.

I do want to mention one issue… the issue of getting your text to wrap. With my current redesigned DataTemplate, my project looks like this:

It scrolls horizontally to a degree that is certainly unhealthy. What is happening is that the TextBlock in the DataTemplate is making a request for space and when it hits a limit, it will start wrapping. Unfortunately for us, when the ScrollViewer in the ListBox has the HorizontalScrollBarVisibility set to “Auto”, it is telling the TextBlock that it has all the room in the world and that it doesn’t need to wrap. So, let’s just change the HorizontalScrollBarVisibility on the ListBox to “Disabled”.

And we’re done.

You can download the source here

JSON – Silverlight – New York Times Tutorial (Part 2) Project Files

Questions and comments are always welcome.

Summary: In this post, I walk through the basics of using Silverlight to query the New York Times Article API and display the results of the query. You can see the final result below.

You can also download source code for this project here.

JSON/Silverlight/New York Times project files

Huge thanks to Josh Holmes, whose JSON/Silverlight tutorial was the base of much of this project.

This project is somewhat code-intensive (and kind of long, expect 30-60 minutes), so if you just want the utility provided here without any of the work, you can skip over to my post on displaying the results, which is strictly a Blend tutorial.

However, I recommend walking through this one since it will help get you to a point of pulling real data from an API, which I’ve found to be a wonderful help as I practice putting together data-based designs. One of the things I’ve been wanting to be able to do as a designer is to explore a data set easily and quickly so that I can have data to play with in my interfaces. I found exactly what I wanted in the New York Times API, but then I found out I had to learn JSON.

“Oh great,” I said to myself, “another technology for me to learn.” But it turned out that I didn’t actually have to learn that much, because Visual Studio does nearly all the work for me.

Super Quick Introduction to JSON

If you’re not interested and you want to get to the business of grabbing New York Times data, you can skip it . It is helpful, but not strictly necessary.

JSON stands for JavaScript Object Notation and is basically just a really handy way to pass data along in a web service. It is very simple… within a set of curly brackets, you will have name/value pairs separated by a colon with each piece of data.
Example:
{
    FirstName : “Matthias”,
    LastName : “Shapiro”,
    Blog : “Designer WPF”
}

This is a JSON object. Arrays are created by using square brackets and JSON obejcts can be placed into a Javascript var. These things are not really related in anyway, but putting them in the same sentence allows me to only write one more example instead of two

Example:
{
    FirstName: “Matthias”,
    LastName: “Shapiro”,
    Siblings : [
    {Name : “Abby”},
    {Name : “Joel”},
    {Name : “Anna”},
    {Name : “John”},
    {Name : “Nate”}
    ]
}

And there we have the basics of JSON.

End of Super Quick Introduction to JSON

What is so awesome about JSON and Silverlight is that Visual Studio 2008 has a set of JSON-friendly classes that make working with JSON a breeze. Which is really handy because the New York Times, which is a dream come true for the new data-gatherer, delivers JSON results. So let’s walk through making a call to the New York Times Article API, handling the data we get back, and putting it into a Listbox for viewing.

First, go to the New York Times Developer site, log in (or register) and get your API key.

Next, start a new Silverlight project in Visual Studio 2008. I named mine “JSONNewYorkTimesTutorial”.

Open your new project in Blend, pull up Page.xaml and add a TextBlock, ListBox, a TextBox and a Button. Name the ListBox “ResultsDisplay” and the TextBox “SearchText”.

Now, my Page.xaml looks like this.

OK… now let’s go to the code-behind for our project go to the event section of the button in Blend and type “PerformQuery” into the “Click” event.

This will automatically insert the necessary code into the code-behind, so pull up Visual Studio. Before we implement a call to the NYT API, lets add some useful stuff. If you have not yet gone to get your Developer key, do so now.

private string myApiKey;
private WebClient callNYT;

public Page()
{
    InitializeComponent();
    myApiKey = “&api-key=(put your api key here. No, you may not have mine)”;
    callNYT = new WebClient();
    callNYT.OpenReadCompleted += new OpenReadCompletedEventHandler(callNYT_OpenReadCompleted);
}

In the code above, we’ve created a string that we can use to apply our unique NYT API key and we’ve created an instance of WebClient to call and receive information from the NYT API. When an object from the NYT API has been received , it will call the OpenReadCompleted event, which will be handled by our callNYT_OpenReadCompleted method.

(By the way, if you’re not getting the proper intellisense for the “Web Client” part, add “using System.Net;” to the top of your file.)

Now on to our button method. There are tons of things we can add to our query to find the exact information we want. But in the interest of simplicity, this post will deal only with a simple text search. To that end, let’s go to our PerformQuery method and turn it into this:

private void PerformQuery(object sender, RoutedEventArgs e)
{
    string NYTQueryBase = “http://api.nytimes.com/svc/search/v1/article”;
    string SearchTerm = “?query=”+ SearchText.Text;
    Uri queryUri = new Uri(NYTQueryBase + SearchTerm + myApiKey);

    callNYT.OpenReadAsync(queryUri);
}

We’ve done two things here. The first is that we built our search query using the query base, the query string and our API key. That was simple enough.

Next, we’ve going to use the WebClient we created to call our new query. When the query has been completed, our program will run the callNYT_OpenReadCompleted method with its result, which will be a JSON object constructed by the NYT servers. We will get back a JSON object with the following:

• offset – We will get 10 results per page. The offset tells us which page of the results we’re on. The default is 0, which gives us results 0 – 9.
• tokens – this is a array of our search terms.
• total – this is an integer indicating of how many results there were for our search.
• results – this is an array of results with the following format
  • body – a portion of the beginning of the article
  • byline – the article byline, usually including the author name
  • date – the date the article appeared, in a “yyyymmdd” format. For example, today would be “20090225”.
  • title – the article title
  • url – a url link to the article

A quick note: The NYT API is extremely flexible and we can actually define how we want our results to come back. This is just the default result format for the purposes of demonstration.

Before we handle this object, we want to create a class for the results. Right click on your project and go to “Add –> Class…”. Name your new class “NYTResult.cs” and make sure it looks like this:

public class NYTResult {
    public string Body { get; set; }
    public string Byline { get; set; }
    public DateTime Date { get; set; }
    public string Title { get; set; }
    public Uri Url { get; set; }
}

I added the following method to the class to handle the date conversion from the NYT format to a .NET DateTime object.

public DateTime formattedDateTime(string NYT_Time)
{
     int year = Convert.ToInt32(NYT_Time.Substring(0, 4));
    int month = Convert.ToInt32(NYT_Time.Substring(4, 2));
    int day = Convert.ToInt32(NYT_Time.Substring(6, 2));
    DateTime finalDateTime = new DateTime(year, month, day);
    return finalDateTime;
}

OK… now we’re really ready to handle the JSON object. Right click on the references in your project and select “Add Reference…”

In  your “Add References” box, select “System.Json” and click “OK”.

Add “using System.Json;” to the references in your Page.xaml.cs file. And, just for good measure, add “using System.Collections.ObjectModel;” as well.

Go to the callNYT_OpenReadCompleted method and enter the following. I’ve tried to comment the code so that I don’t need to further explain it. Side note: I’m not always the best at understanding what is self-explanatory and what I need to elaborate on. If there are any additional questions, post them in the comments and I’ll answer as quickly as I can.

void callNYT_OpenReadCompleted(object sender, OpenReadCompletedEventArgs e)
{
    //grab our result and make a JSON Object out of it
     //    then extract the results array from that object
     JsonObject completeResult = (JsonObject)JsonObject.Load(e.Result);
    JsonArray resultsArray = (JsonArray)completeResult["results"];

    //an observable collection to hold the data and attach it to our ListBox

     ObservableCollection<NYTResult> resultCollection = new ObservableCollection<NYTResult>();

    //iterate through the results and transfer the data from a
     //   JSON object into our nice pretty .NET object
     foreach (JsonObject NYTRawResult in resultsArray)
    {
        NYTResult singleResult = new NYTResult();

        //don’t forget to check your results… an article might not have a
         //  byline or a link
         if (NYTRawResult.Keys.Contains(“body”))
            singleResult.Body = NYTRawResult["body"];
        if(NYTRawResult.Keys.Contains(“byline”))
            singleResult.Byline = NYTRawResult["byline"];
        if (NYTRawResult.Keys.Contains(“date”))
            singleResult.Date = singleResult.formattedDateTime(NYTRawResult["date"]);
        if (NYTRawResult.Keys.Contains(“title”))
            singleResult.Title = NYTRawResult["title"];
        if (NYTRawResult.Keys.Contains(“url”))
            singleResult.Url = new Uri(NYTRawResult["url"]);

        //add our new result to the collection
         resultCollection.Add(singleResult);
    }

    //assign the result as the source for our ListBox
     ResultsDisplay.ItemsSource = resultCollection;

    //take the overall article count and display it
     resultCount.Text = “Number of articles: ” + completeResult["total"].ToString();
}

Now, we can run our project. Type something into the TextBox and hit the button and we get this:

Not exactly the most readable thing ever. So let’s add the following to the ListBox XAML:

DisplayMemberPath=”Title”

Now we get something a little more like this (go ahead and give it a whirl):

Much better. Remember, this is a simple query, so it’s only looking for items that have that word in the article… it might not be in the title.

My next post builds on this one and I walk through building a more useful display for our results. It will be far less code intensive and far more designer centric.

I’ve made the source available for this project. I’ve taken out my NYT API key, so it will not run unless you get your own and put it in.

JSON – Silverlight – New York Times Tutorial Part 1 project files

UPDATE: I’ve made the source code available for download here.

Yeah, yeah… I know it’s long past the time when anyone want to revisit the wonders of the 2008 presidential campaign, but the stars aligned for me to build this thing.

Star #1: I’m been meaning to learn JSON forever because everyone is talking about it.

Star #2: I’ve been meaning to get into pulling data from a publicly available API using a Silverlight application.

Star #3: I’ve been meaning to do something with information visualization in Silverlight ever since I got Ben Fry’s terrific book on Visualizing Data.

Star #4: Tim Heuer challenged his readers to create a Silverlight infoviz application with a time constraint of six days.

And so, due to several late nights and the infinite patience of my wonderful wife, I’ve finished my first data driven Silverlight information visualization. An explanation follows below the app.

The application visually displays how many stories in the New York Times in a given week mentioned one of the presidential candidates. If your favorite candidate does not appear, I apologize. I chose the seven most frequently mentioned candidates in each party.

My journey of exploration began at the New York Times developer site where I got my developer key and started exploring the data from their brand new Article Search API, with which you can search articles in the New York Times as far back as 1981.

Because the NYT API returns a JSON result, that meant I had to learn JSON. I highly recommend it. Super easy. I ended up scraping the data I needed and parsing it into a custom JSON file of my own so I wasn’t making a couple hundred calls to their servers every time I wanted to run my application.

From there, it was actually a simple matter to pull the idealized data into my application and start visualizing it. In case you’re wondering, the placement on the map doesn’t represent anything at all… I was just looking for a good way to show the data and I liked this one.

A special thanks to my wife, the math genius, for reminding me to take the square root my data so that my circles ended up with proportional areas (instead of exponential ones).

There are, of course, several things I would change about this if I had the time. The slider can be flaky, the fonts could use some more work and the code in general is a bit of a disaster. But this is all the time I had and I think it works pretty well.

These are my links for February 20th:

• XAML Guidelines for Creating a Composite UI –
• Andrej Tozon’s blog | Design a Vista-like account display picture for Silverlight application – This is a great starting place for using Expression Design and moving everything into a Silverlight app
• 6 Things I Bet You Didn’t Know About Data Binding in WPF – Nates Stuff – Really valuable tips about WPF Binding and XAML
• Moonlight 1.0 goes live – Miguel de Icaza – Open Source Silverlight implementation for Linux. Works as a Firefox plugin.
• Descry – "As a part of Descry, we are releasing a set of open source, web-based visualizations and an article written by the Jon Udell that serves as a broad introduction to the topic." Silverlight visualizations.

These are my links for February 10th:

• Integrating Silverlight and ASP.NET MVC – Vital information if you're using Silverlight with MVC… Which I think about from time to time even though I have no time to actually do something
• Specialists Versus Generalists: A False Dichotomy? – Pabini Gabriel-Petit posits a counter argument to Jared Spool's discussion on specialists and generalists in UX. Or maybe I like it because Gabriel-Petit pretty much describes me to a tee. (thanks to jalderman)
• Example of using ObservableCollection for dependency injection – Edward Tanguay's has code for a test application that dynamically adds items to the UI when they are added to the observable collection. Nifty little summary app.
• Windows 7 Developer Guide – Release: Windows 7 Developer Guide – I should read this at some point if I want to stay ahead of the game… or at least know what it is I should know. (Thanks to joemcbride)
• WPF (Video) Hackery! Part I – Jer at http://jmorrill.hjtcentral.com has a hack for getting webcam to show up in WPF. Need to try! I got this fantastic webcam for Christmas and I've only goofed around with some AR stuff. (thanks to joemcbride)

I don’t know the answer to the question above… I’m still experimenting in that regard.

But if you have time, Joel Neubeck is asking that question and I would love to see what you think about it. I’ve heard fantastic things about Model-View-Controller (MVC), but I’ve also heard good things about Model-View-View-Model (MVVM).

Thanks to Tim Heuer for the pointer.

These are my links for February 10th:

• Shawn Wildermuth – Drag and Drop in Silverlight 2 – Seems like obvious drag-and-drop stuff. On the other hand, I've built an entire web presence on tutorials about things that should be obvious but aren't. (Thanks to WynApse)
• Silverlight and Encryption – Michael Wolf – Probably the best encryption tutorial for Silverlight I've ever seen. From Michael Wolf… who is part of the Cynergy team that is doing a workshop on good design/development teams at MIX09.
• A Simple Multi-Select ComboBox using Expression Blend – Jobi Joy walks us through creating a multi-select comboBox in Blend.
• Southridge Hands-on-Lab – "extensive hands-on-lab for WPF developers. The six-part lab includes Fundamentals, Custom Controls, Styling, Ribbon, DataGrid, Databinding" thanks to edward_tanguay for the link
• Twitter list: WPF and SL developers – Devin Brown over at Identity Mine posted this Google Docs list of Silverlight and WPF developers