Samples

Why is multitasking missing and how to hide the fact?

Windows Phone 7 at this very moment does not support Multitasking for 3rd party applications. There are a lot of reasons for that and as an IPhone user I could not agree more with this decision. Running different applications parallel means more power consumption, more memory consumption and higher cpu load. These factors directly lead to reduced User Experience, like your battery says goodbye in a couple of hours, the screen is not so smooth when using multitouch, it’s „lagging”, or changing between applications might get really slow.

One of the recurrent questions people ask me in the forums is about the applying of security constraint to the applications being developed. The last releases of useful tools like WCF Ria Services added the capability of bringing the security context from the server to the plugin running into the browser. This let the developer to have the current logged-in user and his roles available to apply rules to elements of the user interface.

With WCF Ria Services you can create easily an AuthenticationDomainContext and when you make a reference to it from a Silverlight project you will have available a class named WebContext.

 Sample RSS Feed application using Windows Phone 7 Series SDK.

Shows RSS feed title list from http://www.visitmix.com/RSS 

Article details showed in WebBrowser control based on user selection in the list.

 RSS app code 

This is Denislav Savkov image slider control ported to windows phone 7 series.

Please find the url of orignal silverlight control.

http://www.silverlightshow.net/items/Image-slider-control-in-Silverlight-1.1.aspx

Ported version of the control. 

PhotoViewer.zip

1. Introduction

In the first part of the article, I tried to describe what is RX Framework and what can be done with it. One thing I’ve missed to mention was how RX could be used for asynchronous service calls. Namely, this is the accent in the second part of the article. For those who missed the first part, you could read it here.

The demo source code could be downloaded from here.

Introduction

This is the second and conclusive article about an example of a Bing Maps extension using Silverlight. Let me briefly recall the objective: in the first article I wrote about the need which may arise when planning an itinerary, I underlined that knowing the elevation profile would be useful. Having this functionality using the Maps Silverlight Control is not difficult. In the following sections we will see how to get elevation data as well as to plot them on a graph. You can enjoy a demo here and download the code here.

I think some of you may have developed an application that requires a lot of roundtrips on the server to retrieve data to be displayed to the user. Every time your application goes to the server it may have to wait for long running query to end its works, perhaps because the data are extracted from an huge database. Then it have to download the data and finally display them onto the screen.

If you have already deal with this kind of interaction you should know that the two connection limit of the web browser can become evident. For some of you that are not aware of this limitation you have to know that due to the RFC 2616 specification, the compliant browsers have not to hammer the network and are limited to make only two simultaneous connections to the server (per domain).

Uploading and downloading images using a WCF service with Silverlight

Quite often, when browsing the web, we encounter a situation where we are required to upload a file. When I want to register myself on a forum, I often get the question if I want to upload an avatar. Or when using a social networking site such as Facebook, I can upload pictures of me doing something that probably no one is interested in. The point I’m trying to make here is that when developing in Silverlight, we’ll also come in a situation where we want our users to upload files such as images to the server.

Introduction

One of the things I found missing in the current Bing Maps product is the possibility to create an elevation surface profile of routes. Perhaps this feature may not seem much on demand but actually affects more people than expected. Think for example about sports events like marathons and cycling races: to see a preview of the elevation profile of the trail would be of great benefit to the participants. But even if you're just simple hikers you might want to know what is the difference in level of your walking or bicycle trip to better understand the effort that it would entail.

Introduction

In the first part of the series, I introduced the application, and created the “ugly duckling” version, where the end user could already browse the and watch the videos. In this part, I am going to add some bling to the app – namely the Intro animation, the ability to skip it, and to replay it. The Intro animation itself is not created with Silverlight, so I will just use it as a video. This part takes heavy use of Visual States, Behaviors and Easings.

Visual States

The application builds on Sample Data for displaying the videos’ metadata, and it uses Visual States to differentiate between the states of the application.