Alex Yakhnin's Blog

Teched in Russia.

priozersk — Mon, 26 Oct 2009 00:10:00 GMT

I have been invited to speak at the Teched conference (Platforma 2010) in Russia. I will be speaking about a wide range of topics on development for Windows Mobile 6.5 plartform such as UI Framework, Gesture API's and Widgets. Marat is going to help me with a part of the presentation. This should be somewhat challenging for me, since I will be presenting in my native (Russian) language and I have not done it in long time (15 years) and I will also need to figure out how a certain terminology is translated into Russian. So if you are in Moscow on November 12 and attending the conference feel free attend my presentation.

Managed wrapper of the Gesture APIs

priozersk — Fri, 28 Aug 2009 21:32:00 GMT

Ron and I did a part 1 of the Webcast on the Gesture APIs in the Windows Mobile 6.5 and a managed wrapper that we created. In this Webcast we talked about GestureRecognizer class. You can catch a recording from here:

http://msevents.microsoft.com/CUI/WebCastEventDetails.aspx?culture=en-US&EventID=1032422141&CountryCode=US

In the Part 2 we will be describing the Physics engine and WAG functionality of the Gesture API's. You can register for this webcast here:

http://msevents.microsoft.com/CUI/EventDetail.aspx?EventID=1032422150&Culture=en-US

The code for the managed wrapper is available at:

http://code.msdn.microsoft.com/gestureswm

Enjoy!

Porting IPhone applications to Windows Mobile

priozersk — Sun, 09 Aug 2009 03:40:00 GMT

An interesting article has been recently published on Msdn that describes the real-world experiences of porting the IPhone application to the Windows Mobile platform.

When reading the article I was pleasantly surprised to find out that the developers end up using my UI framework to reproduce look and feel of the IPhone application. It is very satisfying to know that my work is useful.

Introduction into touch.

priozersk — Mon, 29 Jun 2009 16:20:00 GMT

Take a look at this great introduction into the world of touch screens and gestures by Marcus. He also starts describing the APIs that are available in Windows Mobile 6.5 for handling gestures.

New attractive controls for mobile development.

priozersk — Fri, 26 Jun 2009 16:50:00 GMT

There's a new company that has just released a few really nice controls for .NET Compact Framework and which you can use to develop attractive UIs in your Windows Mobile applications:

http://www.beemobile4.net/

They where nice to let me know that they've learned a lot from my blog and webcasts on creating cool UI's. It is really satisfying that the work that I do is useful for Mobile developers.

WM 6.5 Develper Tool Kit

priozersk — Thu, 04 Jun 2009 05:37:00 GMT

The Windows Mobile 6.5 Developer Tool Kit is available for download. It includes the Emulator images as well as the documentation and the samples on Gesture APIs.

Enjoy!

Identifying VGA resolution on WM devices.

priozersk — Tue, 05 May 2009 00:55:00 GMT

Very often when developing managed applications you need to target both VGA (480x640) and the older QVGA (240x320) type of devices. If the AutoScaleMode property of your form is set to Dpi, your controls such as textboxes. labels, buttons etc... will be scaled automatically. However if your draw images yourself or utilizing the ImageList, the images are not going to be autoscaled for you. During the runtime you can easily identify the VGA resolution by using the following code:

public static bool IsHighResolution(this Form form)

{

SizeF currentScreen = form.CurrentAutoScaleDimensions;

if (currentScreen.Height == 192)

{

return true;

}

return false;

}

This is an extension method which is a part of the ControlExtension class from the ListViewDemo project which you can download from here.

So how would you use that method. Here's a sample function that you can place in your form's code:

private void HandleHiRes()

{

if (this.IsHighResolution())

{

this.imageList1.ImageSize = new Size(32 * 2, 32 * 2);

}

Enjoy...

Overview of the Sync Services v2

priozersk — Sun, 03 May 2009 18:11:00 GMT

Sean Kelley who is the PM for the Sync Services for ADO.NET has recorded a webcast that walks through the new features of the next version of the SyncServices. The team has collected a lot of the feedback from the customers on the first version and tried to incorporate it into vNext. The notable changes are: ability to create database snapshots, P2P synchronization, batching, etc... Check out the Sean's webcast for more details:

https://msevents.microsoft.com/CUI/Register.aspx?culture=en-US&EventID=1032413045&CountryCode=US&IsRedirect=false

The article on Compelling UI has been published.

priozersk — Wed, 29 Apr 2009 06:08:00 GMT

My article on the UIFramework that I presented during my webcasts has been published on MSDN:

http://msdn.microsoft.com/en-us/library/dd630622.aspx

Update to MobileMVC with Container

priozersk — Thu, 23 Apr 2009 03:56:00 GMT

I've recently made a substantial update to the MobileMVC framework. I've added the ability to utilize a (D)epenendcy (I)njection container by adding IControllerProvider interface into the framework which looks like this:

public interface IControllerProvider

{

Controller GetController(string name);

Controller GetController(Type type);

Controller GetController<T>();

Controller GetController<T>(IView view);

void RegisterController(Controller controller);

}

This interface gets used in the new class Navigator which could be used instead of NavigationService to navigate between the controllers since it implements the same methods such as Navigate, GoBack, GoForward etc... The Navigator class is exposed as a singleton via the property in the Controller class:

/// <summary>

/// Gets an instance of the Navigator.

/// </summary>

public Navigator Navigator

{

get

{

return Navigator.Current;

}

The Navigator class also includes the following static method:

/// <summary>

/// Sets the IControllerProvider to use.

/// </summary>

/// <param name="controllerProvider"></param>

public static void SetControllerProvider(IControllerProvider controllerProvider)

{

if (navigator == null)

{

navigator = new Navigator(controllerProvider);

}

As you can see the SetControllerProvider method accepts as a parameter an instance of the IControllerProvider which you will need call when your application is initialized.

Before diving into the full usage sample let's talk about the DI container. As we know, there's not much of the DI and IoC containers exist for .NET CF right now, however Paterns & Practices team has been quetly working on the update of the Mobile Application Blocks that where released a few years back. P&P has recently posted a Community Drop of the code refresh for the Mobility Block on the Codeplex and it includes the new block which is called ContainerModel. P&P has decided to utilize the Funq container that was developed by Daniel Cazzulino. So, I've taken this container and updated the sample for the MobileMVC to make a use of it.

Let's continue on the sample of how you can utilize the new features in the MobileMVC framework. I have modified the existing sample MVCDemoClient (a part of the download of the framework), so let's see how we'd initialize container with the views and controllers:

private static void Initialize()

{

container = new Container();

// Register Login view and controller

container.Register<LoginForm>(c => new LoginForm());

container.Register<LoginController>(c =>

new LoginController(c.Resolve<LoginForm>()))

.InitializedBy((c, v) => v.Container = c);

// Register Search view and controller

container.Register<SearchForm>(c => new SearchForm());

container.Register<SearchController>(c =>

new SearchController(c.Resolve<SearchForm>()))

.InitializedBy((c, v) => v.Container = c);

// Register Search view and controller

container.Register<DetailForm>(c => new DetailForm());

container.Register<DetailController>(c =>

new DetailController(c.Resolve<DetailForm>()))

.InitializedBy((c, v) => v.Container = c);

// Register data model

container.Register<Products>(c => new Products());

// Set ControllerProvider

Navigator.SetControllerProvider(new ControllerProvider(container));

}

In the code above when we register a controller, you can see that we call: .InitializedBy((c, v) => v.Container = c). This means that when an instance of the controller will be created we want to assign the same instance of the container to the Container property which I've added to the controller. We also make a call to the SetControllerProvider method and passing and instance of the ControllerProvider class which as you can guess implements IControllerProvider interface and makes use of the Container:

public class ControllerProvider : IControllerProvider

{

private Container container;

public ControllerProvider(Container container)

{

this.container = container;

}

#region IControllerProvider Members

public Controller GetController<T>()

{

return this.container.Resolve<T>() as Controller;

}

public Controller GetController<T>(IView view)

{

Controller controller = this.container.Resolve<Controller>();

controller.View = view;

return controller;

}

// … Other methods ommitted for brevity

#endregion

}

After this short preparation we can now modifiy our code to use the Navigator class. This is how we can show the SearchForm from the LoginController:

private void ShowSearchView()

{

//SearchController controller = new SearchController(new SearchForm());

//NavigationService.Navigate(controller);

this.Navigator.Navigate<SearchController>();

}

Ability to access the Container from the controller is also giving us much more separation from the Data Model or other services that you may use in the application. For example this is how we can get access to the Products data model in the SearchController:

// ViewLoaded event from the view

private void OnViewLoaded(object sender, EventArgs e)

{

// Show busy cursor

Cursor.Current = Cursors.WaitCursor;

// Get an instance from the container

Products products = this.Container.Resolve<Products>();

// Populate data

products.PopulateList();

// Assign the Model

this.view.ViewData.Model = products;

// Notify the view of the changes

this.NotifyView();

// Restore the cursor

Cursor.Current = Cursors.Default;

}

Overall, I think the usage of the container with the MVC pattern gives you much more flexibility when designing your applications. It allows you to decouple the access to the application services giving you more room during the unit testing as well as making changes to the application without breaking too many dependencies.

You can find the updated version of the MobileMVC framework and the sample in the downloads section of the codeplex project:

http://mobilemvc.codeplex.com/Release/ProjectReleases.aspx?ReleaseId=26507

More memory for managed apps.

priozersk — Fri, 10 Apr 2009 22:52:00 GMT

Check out the Rob's blog post in which he describes the technique that can help you to allocate less memory when creating managed applications on Windows Phones:

http://blogs.msdn.com/robtiffany/archive/2009/04/09/memmaker-for-the-net-compact-framework.aspx

Bluetooth on the emulator.

priozersk — Thu, 09 Apr 2009 07:04:00 GMT

Would you like to develop applications that utilize the bluetooth functionality on the WM emulator? Now you can. Check out this article on CodeProject:

http://www.codeproject.com/KB/mobile/bth4devemul.aspx

Dimming the background.

priozersk — Tue, 31 Mar 2009 17:00:00 GMT

I've received a question from the customer the other day asking me how he can implement functionality of "dimming" background effect when a message box is shown in his Windows Mobile application. In fact it should be pretty easy to do utilizing the DrawAlpha method from the GraphicsExtender class that I showed you in this webcast. Take a look at the following code snippet:

protected override void OnPaint(PaintEventArgs e)

{

// Create a temp bitmap

Bitmap dimBackGround = new Bitmap(this.Width, this.Height);

Graphics gxTemp = Graphics.FromImage(dimBackGround);

// Color it black

gxTemp.Clear(Color.Black);

// Draw it with alpha transparency

e.Graphics.DrawAlpha(dimBackGround, 100, 0, 0);

// Clean up

gxTemp.Dispose();

dimBackGround.Dispose();

}

The code above shows OnPaint override method in the BackgroundForm class that I've added to the demo project. I've set the FormBorderStyle to None and WindowState to Maximized for this from to make it full screen.

So, now before displaying a message box you will need to show the BackroundForm:

BackgroundForm form = new BackgroundForm();

form.Show();

MessageBox.Show(txtMessage.Text);

form.Close();

And here's the result:

Download the sample code from here.

TechDays - 24 hour virtual event

priozersk — Thu, 26 Mar 2009 17:42:00 GMT

I will be participating in the TechDays next week on April 1st. It's a 24 hour virtual event with almost a hundred sessions that will be repeated for different time zones for people across the globe. I was asked to repeat the Creating Compelling and Attractive UIs for Windows Mobile Applications session. I am going to have two live sessions 10:30 pm GMT and 1:30 pm GMT. Chistopher Fairbairn will be presenting the same session in the Asia Pacific time zone.

Another Webcast on controls customization.

priozersk — Mon, 16 Mar 2009 19:24:00 GMT

Next week I am going to present a second part of the series on creating attractive UIs on Windows Mobile devices. This time I will show you how to customize built-in controls that come with .NET CF, such as TextBox, DataGrid, ListView etc...

You can register for the web cast here:

http://msevents.microsoft.com/CUI/WebCastEventDetails.aspx?EventID=1032408754&EventCategory=4&culture=en-US&CountryCode=US

UPDATE:

The code from the session is available for download from:

https://code.msdn.microsoft.com/Release/ProjectReleases.aspx?ProjectName=uiframework&ReleaseId=2315