http://msdn.microsoft.com/en-us/library/system.runtime.serialization.datacontractserializer_members.aspx

So as it turns out, your XML stream must have the XML Nodes in Alphabetical Order when trying to deserialize XML data into an object.  Very wierd.

So I needed to create a hover button.  The idea is that when the mouse rolls over the button the image will flip between a normal and ‘over’ version of the button image.  This is the same thing as old school image rollover code we have all used before.  There is an image that you use for a button in the ‘normal’ or ‘off’ state and when the mouse rolls over the image the picture changes to the ‘over’ or ‘on’ state.

It is pretty easy to do this statically.  Edit the button style, slap a couple of images in the ControlTemplate and tie that to the Normal and MouseOver visual states and you are done.

But what if you want to be able to use that same style for all your buttons and you want to be able to databind the Normal and MouseOver images?

This was pretty easy with a trick here or there.

First, we need to create a HoverButton class that inherits from the standard Button.  We need to do this because we need 2 new properties for our Normal and Over image url’s.

using System;

using System.Net;

using System.Windows;

using System.Windows.Controls;

using System.Windows.Documents;

using System.Windows.Ink;

using System.Windows.Input;

using System.Windows.Media;

using System.Windows.Media.Animation;

using System.Windows.Shapes;

namespace MySLApplication.Local

{

    public class HoverButton : Button

    {

        public string NormalImageUrl

        {

            get { return (string)GetValue(NormalImageUrlProperty); }

            set { SetValue(NormalImageUrlProperty, value); }

        }

        public static readonly DependencyProperty NormalImageUrlProperty =

            DependencyProperty.Register("NormalImageUrl", typeof(string), typeof(HoverButton), 

            new PropertyMetadata(""));

        public string MouseOverImageUrl

        {

            get { return (string)GetValue(MouseOverImageUrlProperty); }

            set { SetValue(MouseOverImageUrlProperty, value); }

        }

        public static readonly DependencyProperty MouseOverImageUrlProperty =

            DependencyProperty.Register("MouseOverImageUrl", typeof(string), typeof(HoverButton), 

            new PropertyMetadata(""));

    }

}

This is the button you will place on your design surface instead of the regular button.  This one gives us NormalImageUrl and the MouseOverImageUrl.  These properties we will set to the URL for the images we want to use for our normal state and mouse over state.

Next is the Style (see the zip file at the bottom of this post for the actual code).  Since the Style is so big, I will describe the important pieces to you.

First, your XAML that contains this style code needs to have a namespace reference to the HoverButton’s namespace.  I named mine local so you will see my TargetType set to local:HoverButton.

xmlns:local="clr-namespace:MySLApplication.Local"

So the style starts out like this:

<Style x:Key="HoverButtonStyle" TargetType="local:HoverButton">
            <Setter Property="Background" Value="#FF1F3B53"/>
            <Setter Property="Foreground" Value="#FF000000"/>
            <Setter Property="Padding" Value="3"/>
            <Setter Property="BorderThickness" Value="0"/>
            <Setter Property="Height" Value="36" />
            <Setter Property="Width" Value="118" />
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="local:HoverButton">
                        <Grid>
                            <VisualStateManager.VisualStateGroups>
                                <VisualStateGroup x:Name="CommonStates">

Note the TargetType in both instances is pointed to the local namespace and the HoverButton class name.  The real magic occurs in the ControlTemplate portion of the code.  Here there are several Visual States defined.  We are concered with two of them (feel free to extend this to the others also): Normal and MouseOver.

You will notice in each of the two Visual States we are concerned with there is a storyboard.  The StroryBoard executes when the visual state is entered.  So for example, when the button starts out it is in the Normal state.  When the control is rendered the Normal visual state causes the storyboard defined here to execute:

<VisualState x:Name="Normal">
    <Storyboard>
        <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="(UIElement.Visibility)" 
        Storyboard.TargetName="OverImage">
            <DiscreteObjectKeyFrame KeyTime="0">
                <DiscreteObjectKeyFrame.Value>
                    <Visibility>Collapsed</Visibility>
                </DiscreteObjectKeyFrame.Value>
            </DiscreteObjectKeyFrame>
        </ObjectAnimationUsingKeyFrames>
        <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="(UIElement.Visibility)" 
        Storyboard.TargetName="NormalImage">
            <DiscreteObjectKeyFrame KeyTime="0">
                <DiscreteObjectKeyFrame.Value>
                    <Visibility>Visible</Visibility>
                </DiscreteObjectKeyFrame.Value>
            </DiscreteObjectKeyFrame>
        </ObjectAnimationUsingKeyFrames>
    </Storyboard>
</VisualState>

What happens here is that the StoryBoard sets the OverImage’s Visibility property to Collapsed and the NormalImage’s Visibility property to Visible. 

Before confusion sets in, scroll down to the bottom of the style.  You will see the two images we just discussed.

<ContentPresenter x:Name="contentPresenter" ContentTemplate="{TemplateBinding ContentTemplate}" 
   Content="{TemplateBinding Content}" 
   HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" 
   Margin="{TemplateBinding Padding}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
<Image x:Name="NormalImage" DataContext="{TemplateBinding NormalImageUrl}" Source="{Binding}" />
<Image x:Name="OverImage" DataContext="{TemplateBinding MouseOverImageUrl}" Source="{Binding}" />

The two images defined inside the button’s visual surface are the actual images you will see at runtime.  Notice that we had to set the DataContext of the Image control to the property NormalImageUrl and MouseOverImageUrl and THEN set the Source property to {Binding}.  You need this little trick in order to allow databinding to convert the string based URL to an ImageSource.

So now we are good to go.  We can use our HoverButton like this:

<local:HoverButton Content="" Height="36" HorizontalAlignment="Left" 
    Margin="508,558,0,0" x:Name="btnSpin" VerticalAlignment="Top" Width="118" 
    Click="btnSpin_Click" Style="{StaticResource HoverButtonStyle}"
    NormalImageUrl="http://yourdomain.com/Normal.png"
    MouseOverImageUrl="http://yourdomain.com/Over.png"/>

So now you can specify the Normal and MouseOver images for your button.  The same style can be used for all these hover buttons, just specify the 2 images and you are set. 

I was using Blend 4 to do some simple animations then copy and pasting the storyboard for use on other objects in my application.  When I executed the Begin() method on the storyboard I would get the following:

Cannot resolve TargetProperty (UIElement.RenderTransform).(CompositeTransform.TranslateY) on specified object.

My XAML was pretty basic.  I finally noticed that Blend had populated the RenderTransform property for me on the working objects.  When I cut and pasted and updated the target object I failed to add the render transform.  Doing so fixes the problem:

Working:

<local:Tile ImageUrl="/SL;component/Images/02_100x100.png" Margin="0,200,0,0" Height="100"
 Width="100" VerticalAlignment="Top" x:Name="Tile_2"
 RenderTransformOrigin="0.5,0.5" >
   <local:Tile.RenderTransform>
        <CompositeTransform/>
   </local:Tile.RenderTransform>
</local:Tile>

Not working:

<local:Tile ImageUrl="/SL;component/Images/02_100x100.png" Margin="0,200,0,0" Height="100"
 Width="100" VerticalAlignment="Top" x:Name="Tile_2"
 RenderTransformOrigin="0.5,0.5" >
</local:Tile>

So if you get this message it is basically telling you that you are missing the RenderTransform property on the target object.

This how-to will show you a few simple steps to making a clipping path in Blend 4.  Below is a mockup of my basic canvas (this is a PNG imported into Blend).  I want to make the green area visible and I want to clip the while rectangles out of the image.  Eventually, I will place some animated elements where the white rectangles are.

The first thing you want to do is to draw rectangles where you want the image to be visible.

Now that I have all of my purple rectangles drawn out I am ready to convert them to a clipping path.

Remember, the rectangles are the areas that will be visible on the clipped object.

Choose the direct select tool: and select all of your rectangles.  Hold down the CTRL key and you can multi-select.  You can also select the rectangles from the Objects and Timeline window.

Choose Object | Path | Convert to Path from the Blend menu.  This converts all your rectangles to a path which we will in turn convert to a clipping path.

Next, go back to Object | Path on the menu and choose Make Compound Path.  This will make one complex path from your individual paths.

Now that you have one compound path select the Path object from the Objects and Timelines window.  Now you can go back to Object | Path and you have the option to Make Clipping Path.

Now you choose the object to clip and you will now have a clipped object (an image in my case). 

Here is the end result in the Blend designer:

And here is the nice clean XAML you generated (please note, for space constraints I truncated the path data in the Clip property):

    <Grid x:Name="LayoutRoot" >
        <Image Margin="0" Source="Images/game-mockup.png" Stretch="Fill" 
         Clip="M0.5,0.5 L799.5,0.5 L799.5,202.5 L0.5,202.5 z M0.5,203.5 ... z">
        </Image>
    </Grid>

The UI for the converter kind of stinks right now because I have been concentrating on functionality.  I am now rendering XAML via plug-in modules.  In addition a preview of the rendered XAML is displayed after generating the XAML.

The UI is really basic right now:

Click the Load Mockup button to locate a .BMML mockup file.

The BMML document is parsed into a set of .NET objects.  For now, the controls are displayed in a grid.  This is going to be removed.  It was mainly used while coding the Mockup XML parsing logic.

Clicking generate will generate the XAML in the texbox at the bottom of the form.

In addition to generating the XAML, it is parsed at runtime and the Mockup is compiled at runtime and previewed.

That is the preview of the XAML rendered from my mockup below:

I still need to include the properties and sample data in the Xaml controls.  But for now, we have a start.

The following code creates a UriToBitmapImage value converter.  Simply reference the converter in your databinding and you will be able to data bind an Image control to a URL and have it displayed on your WPF surface.

First, the value converter code:

namespace MyApp.Local
{
    public class UriToBitmapImageConverter : IValueConverter
    {
        public object Convert(object value, Type targetType, object parameter,
             CultureInfo culture)
        {
            BitmapImage image = new BitmapImage();
            if (value != null)
            {
                try
                {
                    image.BeginInit();
                    image.CacheOption = BitmapCacheOption.OnLoad;
                    image.CreateOptions = BitmapCreateOptions.IgnoreImageCache;
                    image.UriSource = new Uri((string)value, UriKind.Absolute);
                    image.EndInit();
                }
                catch
                {
                    image = null;
                }
            }

            return image;
        }

        public object ConvertBack(object value, Type targetType, object parameter, 
               CultureInfo culture)
        {
            throw new Exception("The method or operation is not implemented.");
        }
    }
}

Add the value converter to your project and compile.

Next, you need to reference the namespace that contains this new class on the WPF Window/Page/Control that you wish to use the converter. (You can also add your converters at the App level.)

xmlns:loc="clr-namespace:MyApp.Local"

I added the UriToBitmapImageConverter class to the MyApp.Local namespace.  Thus, I needed to add a reference to the CLR namespace in my XAML in order to use the converter.

Next, you need to add the converter to your XAML page’s resources:

   <Page.Resources>
        <loc:UriToBitmapImageConverter x:Key="UriToImageConverter" />
   </Page.Resources>

Here I used Page.Resources because I am adding this converter to a WPF Page.  It would be Window.Resources if you are working with a WPF Window or UserControl.Resources if you are adding this to a UserControl.

Now, simply data bind your image:

<Image Margin="8,7,4,8" 
      Source="{Binding ImageUri, Converter={StaticResource UriToImageConverter}}" 
      Stretch="Fill" d:IsHidden="False"/>

In the Source attribute I am data binding a URL / URI which is of type string.  This string is then passed through the UriToImageConverter and output is a BitmapImage object that downloads the image dynamically and displays it.

If I have some extra time, or requests, I will build a sample application to demonstrate.

Today the mockuptoxaml open source project officially kicked off.  The code and the project is not yet publicly published on Codeplex yet.  I am getting the code and the first alpha release of the application ready.  It is in its infancy.  I will post on my blog the progress of the application until it is officially available on codeplex.

Many thanks to Balsamiq for providing me with a license code free of charge.

So my baseline mockup looks like this:

Version 0.1 of the application :D generates this crude WPF form.  As you can see there is a lot of work to do, but it is slowly coming together.

So I found this cool mockup tool that will export to XML a nifty screen mockup.  I have decided to spend a few hours on a converter that will let me input a mockup XML file and output a WPF or Silverlight XAML file.  Seems easy enough.

In many cases you will need to set the visibility of a control based on a value of a property of your ViewModel class.  There are several ways to accomplish this.  The most reusable manner of accomplishing this is to use a value converter to convert the boolean value to a Visibility enumerator.  It sounds complicated but it is super easy.

Note: Before I continue I would like to state that this is an example simplified in order to describe this concept.  The code in this example databinds the IsChecked property of a CheckBox to the view model then databinds that boolean property to the Visibility property of the Button control.  In XAML you can property bind the two controls but that is not what this example is about.  Instead of making this a long example with database calls and other complications I wanted to make this as simple and clear cut as can be.  So if you are looking to databind the property of one control to the property of another this is not the right article for you.

So to demonstrate the value converter we will DataBind the (bool) IsChecked property of the CheckBox to the (bool) IsButtonVisible property of the MainWindowViewModel class.  The Visibility property of the Button control is databound to the same (bool) IsButtonVisible property of the MainWindowViewModel class.

So the XAML for this Window looks like this:

<Window x:Class="ValueConverterExample.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:local="clr-namespace:ValueConverterExample.Local"
        Title="MainWindow" Height="218" Width="196">
    <Grid>
        <Grid.Resources>
            <local:BooleanVisibilityValueConverter x:Key="BoolToVisible" />
        </Grid.Resources>
        <Button Content="Button" Height="23" HorizontalAlignment="Left" Margin="51,110,0,0"
          Name="button1" VerticalAlignment="Top" Width="75" 
          Visibility="{Binding Path=IsButtonVisible,Converter={StaticResource BoolToVisible}}" />
        <CheckBox Content="Is Button Visible?" Height="16" HorizontalAlignment="Left"
          Margin="36,56,0,0" Name="checkBox1" VerticalAlignment="Top" 
          IsChecked="{Binding IsButtonVisible}" />
    </Grid>
</Window>

Note there is a Grid.Resources section in the XAML.  This section is making available to the controls on the Grid the BooleanVisibilityValueConverter object and is naming it BoolToVisible.  This will allow any control on this Grid to use that value converter.  In order to do this, I had to include a namespace that I called local in the Window tag declaration.  This sets up a reference to the Namespace where the Value Converter class resides.

Next, in the Button control’s XAML you see that the Visibility Property is DataBound to the IsButtonVisible property of the DataContext.  Below is the code behind for this Window:

namespace ValueConverterExample
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        MainWindowViewModel viewModel = new MainWindowViewModel();

        public MainWindow()
        {
            this.DataContext = viewModel;
            InitializeComponent();
        }
    }
}

And the code for the MainWindowViewModel is located below:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.ComponentModel;

namespace ValueConverterExample.ViewModel
{
    public class MainWindowViewModel : INotifyPropertyChanged
    {
        public event PropertyChangedEventHandler PropertyChanged;


        private bool _IsButtonVisible;
        public bool IsButtonVisible
        {
            get { return _IsButtonVisible; }
            set
            {
                _IsButtonVisible = value;
                if (PropertyChanged != null)
                    PropertyChanged(this, new PropertyChangedEventArgs("IsButtonVisible"));
            }
        }

    }
}

As you can see the IsButtonVisible property which both the CheckBox and Button are databound is a boolean.  This is possible via the ValueConverter:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Data;
using System.Globalization;
using System.Windows.Media;
using System.Windows;

namespace ValueConverterExample.Local
{
    public class BooleanVisibilityValueConverter : IValueConverter
    {
        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        {
            if (value != null)
            {
                if (((bool)value) == true)
                    return Visibility.Visible;
                else
                    return Visibility.Collapsed;
            }

            return Visibility.Collapsed;
        }

        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
        {

            throw new Exception("The method or operation is not implemented.");

        }


    }
}

This value converter code will accept a Boolean value in, and spit out a Visibility enum.  The magic happens in this databinding expression for the button control’s visibility property:

Visibility="{Binding Path=IsButtonVisible,Converter={StaticResource BoolToVisible}}"

Here we are setting the binding to the IsButtonVisible property of the DataContext.  In addition we are telling the DataBinder to use the converter named BoolToVisible.  Remember we gave our BooleanVisibilityValueConverter class a key name of BoolToVisible when we defined the Grid Resources.

Attached is a sample project.  I hope this helps someone!