A Windows Phone 7 behavior to show an image background for a search string - Init

<body> <h1>A Windows Phone 7 behavior to show an image background for a search string</h1> <p><a href="http://feedads.g.doubleclick.net/~a/Y83HNQprbbiWCzm8h_ieL5SXHE0/0/da"><img src="http://feedads.g.doubleclick.net/~a/Y83HNQprbbiWCzm8h_ieL5SXHE0/0/di" border="0" ismap="true"></img></a><br/> <a href="http://feedads.g.doubleclick.net/~a/Y83HNQprbbiWCzm8h_ieL5SXHE0/1/da"><img src="http://feedads.g.doubleclick.net/~a/Y83HNQprbbiWCzm8h_ieL5SXHE0/1/di" border="0" ismap="true"></img></a></p><p>On New Year’s Eve I can’t help but writing this last bit of 2011: yesterday on a <a href="http://twitter.com/#!/search/%23wp7nl" target="_blank">#wp7nl</a> developer’s meet up, which was basically a free-for-all fun hacking event organized by <a href="http://blogs.microsoft.nl/blogs/mhoekstra/default.aspx" target="_blank">Matthijs Hoekstra</a>, I wrote a little thingy for <a href="http://www.microsoft.com/windowsphone/" target="_blank">Windows Phone 7</a> that accepts a string, tries to find an image for it using Bing Image search and displays it as a background. Of course it’s a behavior – I write behaviors a dozen, because the concept of reusable dynamic behavior is something that fits very well with the way I think. Call me the behaviornator if you like ;-)</p> <p>It’s very simple, it’s quite fun, demonstrates at little Rx usage, makes quite unusual use the of Bing Image Search api - and it will play a supporting act in my newest Windows Phone 7 app. The basic structure of the behavior is set up utilizing the #wp7nl library <a href="http://dotnetbyexample.blogspot.com/2011/11/safe-event-detachment-base-class-for.html" target="_blank">SafeBehavior</a> that I described earlier: </p><pre style="font-size: 12px">using System; using System.Linq; using System.Net; using System.Windows; using System.Windows.Controls; using System.Windows.Media; using System.Windows.Media.Imaging; using System.Xml; using System.Xml.Linq; using Microsoft.Phone.Reactive; namespace Wp7nl.Behaviors { /// <summary> /// A behavior that puts an image on the background of the Attched object /// using Bing Image Search /// </summary> public class DynamicBackgroundBehavior : SafeBehavior<Panel> { private ImageBrush backgroundBrush; public DynamicBackgroundBehavior() { Opacity = 1.0; } #region SearchString public const string SearchStringPropertyName = "SearchString"; /// <summary> /// The search string to be used on Bing Maps /// </summary> public string SearchString { get { return (string)GetValue(SearchStringProperty); } set { SetValue(SearchStringProperty, value); } } public static readonly DependencyProperty SearchStringProperty = DependencyProperty.Register( SearchStringPropertyName, typeof(string), typeof(DynamicBackgroundBehavior), new PropertyMetadata(String.Empty, SearchStringChanged)); public static void SearchStringChanged(DependencyObject d, DependencyPropertyChangedEventArgs e) { var behavior = d as DynamicBackgroundBehavior; if (behavior != null) { behavior.StartGetFirstImage((string)e.NewValue); } } #endregion /// <summary> /// Bing search key /// </summary> public string BingSearchKey { get; set; } /// <summary> /// Stretch used for the image /// </summary> public Stretch Stretch { get; set; } /// <summary> /// Opacity used for the image /// </summary> public double Opacity { get; set; } } }</pre> <p>In short, this behavior has four properties:</p> <ul> <li>Opacity <li>Stretch <li>BingSearchKey <li>SearchString</li></ul> <p><a href="http://lh3.ggpht.com/-AQ4UVdGYxDc/Tv8_V_tECBI/AAAAAAAAHDk/3hL55-6AUnU/s1600-h/BingSearchApi%25255B3%25255D.png"><img style="background-image: none; border-right-width: 0px; padding-left: 0px; padding-right: 0px; display: inline; float: right; border-top-width: 0px; border-bottom </body>