Introducing the November CTP: What’s New In Windows Presentation Foundat= ion

Creating a Drawing Without Using the Timing Engine<= span style=3D'color:windowtext;display:none;mso-hide:screen;text-decoration:none; text-underline:none'>. 18

Creating a VisualBrush. 18

HitTesting Changes 18

ItemsControl Changes 19

Typography Changes to Subscript and Superscipt = 19

Menu Changes 19

DocumentStructures Changes 20

Removal of MonthCalendar and DatePicker = 20

TimeManager removed. 20

Acknowledgements 20

Summary

In November 2005, Microsoft released a Community Technology Preview of Windows Presentation Foundation, the new presentation subsystem for Windows that unifies develop= ment of documents, graphics, and applications into a common platform. In this article, we'll take a brief look at some of the new features that are part = of the November CTP as well as the changes that have been made to since the September 2005 CTP.

<= /span>

Download the code sample.

<= /span>

Introduct= ion

The Microsoft Wind= ows Presentation Foundation (formerly code named "Avalon") provides t= he foundation for building applications and high fidelity experiences in Vista, blending together application UI, documents,= and media content, while exploiting the full power of your computer. The functionality extends to the support for Tablet and other forms of input, a more modern imaging and printing pipeline, accessibility and UI automation infrastructure, data driven UI and visualization, as well as the integration points for weaving the application experience into the Windows shell. =

<= /span>

For information ab= out downloading the CTP, please see the release notes.

<= /span>

For an overview of= WPF, see the overview white paper. (http://msdn.microsoft.com/library/default.asp?ur= l=3D/library/en-us/dnlong/html/hgtobeta1.asp)

<= /span>

Av= alon November Community Technical Preview

There are some exc= iting, new features in this release, which will be enumerated below. And, for those who worked with the September 2005 CTP, there are changes. This article will touch on some of those changes, but it is not comprehensive.

Note on C= ommunity Technology Previews

Community Technical Preview (CTP) builds do not go through the same rigorous testing that beta builds undergo. While betas receive a much higher level of testing and feature work, CTPs are int= ended to expose developers to the latest working build. CTPs= are therefore unsupported, prerelease software and there are some precautio= ns you should take. Please read the latest Readme = and Installation Guides before you download or install pre-release software.

<= /span>

Exploring= New Features
<= /span>

CompositionTarget=

<= /span>

The WPF animation = engine is powerful. The ability to w= ire up animations to any property on any Avalon element opens up many exciting possibilities for creating dynamic user interfaces. While the animation engine is incredibly powerful, it doesn= 217;t meet all scenarios, especially when conditions (e.g., physics, collisions) aff= ect the course of an animation on a finer time scale, when animations need to create visuals, or when post-layout animations need to take place. Thus, the introduction of the CompositionTarget API, which allows the ability to create custom animations based on a per-frame callbac= k.

The CompositionTarget.Rendering event fires during Avalon’s rendering. To use Compos= itionTarget.Rendering you simply register an EventHandler delegate to= the static Rendering method on CompositionTarget. You can create any effect you desi= re in the handler method and it will get called once per frame. Each time that Avalon marshals the visual tree across a channel into the composition tree and/or makes updates= to the composition tree, your animation will be updated. This occurs after layout has been computed; however if you affect layout in your delegate it will be computed once more before rendering. F= or more on the architecture of Avalon, see Chris Anderson and Greg Schechter̵= 7;s PDC talk here (http://commnet.microsoftpdc.com/content/sessions.aspx).

<= /span>

Adding or removing= a rendering delegate while the event is firing will be delayed until after the event is finished firing. This is consistent with how MulticastDelegate based events are handled in the CLR. Also note that rendering events are not guaranteed to be called in a= ny particular order. If you have multiple delegates that rely on a particular order, you should register a single Rendering event and multiplex them in the correct order yourself.

<= /span>

Let’s take a= look at a simple sample. The code sample below will create an application that rand= omly changes the background color on a Page.&nb= sp; It should be noted that in practice you could do this with a custom ‘random color’ animation, however this example is meant to simp= ly show how to hook the event rather than best practices of what to do in the event.

<= /span>

Random rand =3D new Random();

public Page1()

= : base()

{

= CompositionTarget.Rendering +=3D UpdateColor;

}

protected v= oid UpdateColor(object sender, EventArgs e)

{

= //set a random color

= this.Background =3D new SolidColorBrush(

= &nb= sp; Color.FromRgb((byte)rand.Next(255),

= &nb= sp; = (byte)rand.Next(255),

= &nb= sp; = (byte)rand.Next(255)));

}

<= /span>

As you can see abo= ve, registering UpdateColor will cause the pageR= 17;s background brush to be updated every time Avalon renders this page. Running this can be a bit harsh on= the eyes, but it gives you a sense of how the API works. The complete source for this is in= cluded in the associated download with this article.

<= /span>

If you discover th= at your animation runs at different speeds on different computers, it may be caused= by the fact that the animation is not frame rate independent. Depending on the system you are ru= nning on and the work load of that system the Rendering event may be called a different number of times per second. To make your animation frame rate independent, you should base your animations on real time. One technique to achieve this would be to create a Paralle= lTimeline to track the elapsed time between frames.&= nbsp; In the AnimateMotion sample, which demonstrates a rectangle that follows a mouse lagging b= ehind with some physics effects, a TimeTracker class = is available that implements this technique.

<= /span>

Lastly, you may be interested in creating effects that involved the creation of visuals, as opposed to simply manipulating visuals that are already part of the tree. The problem you may encounter is w= here to actually put the visual. F= or example, consider a fireworks effect. This effect would act like a decorator and whenever the child elemen= t is clicked, a burst of ‘fireworks’ would animate outwards and fall down with gravity.

<= /span>

You could make the fireworks with Rectangle shapes and radial gradients, adding them to the pa= rent of the effect. However, if the parent is a decorator itself, it can only ha= ve a single child, so it would impose a limitation on where your effect can be used. Also, the performance of adding many shapes is not as good as adding visuals to a drawing context. As such, you might decide to rende= r the fireworks in the effects OnRender method. This too has a problem; the visual= s from OnRender appear before (under) the child visuals. What we really want = is a decorator like class that has a method similar to OnRe= nder, but that puts the visuals after the child.= An example of how to implement such a class can be found in OverlayRenderDecorator.cs in the CreateVisuals sample.

<= /span>

PropertyTriggers<= /span>

<= /span>

Triggers now suppo= rt the EnterActions and ExitActions collections, which effectively allow for animations to be initiated on any = kind of trigger. Because these col= lections have been added to the TriggerBase class, all o= f the derived Trigger classes now support these collections. Before this CTP, only EventTriggers supported starting animations through i= ts Actions collection, which allowed you to begin a storyboard when a routed e= vent was fired. Now, all triggers have the ability to initiated animations. The ability to begin storyboard on= these other kinds of triggers is important, because there are many cases where you want an animation to begin, but there isn’t necessarily an event fired that you can subscribe to. &nbs= p;

<= /span>

For example, anima= tions can now be initiated based on the values of properties. This can be seen in the sample bel= ow, which starts an animation when the IsMouseOver property changes to true. It = kicks off another animation when the property returns to false.

<= /span>

<Grid.Resources>

= <Setter.V= alue>

= <SolidCol= orBrush Color=3D"Orange" />

= </Setter.= Value>

</Setter<= /span>>

<Style.Triggers>

= <Trigger<= /span> Property= =3D"IsMouseOver<= /span>" Value=3D"True= ">

= <Trigger.= EnterActions>

= <BeginSto= ryboard>

= <Storyboa= rd>

= <DoubleAn= imation Storyboard.TargetProperty=3D"Opacity"

= To=3D"1" Duration=3D&qu= ot;0:0:1" />

= </Storybo= ard>

= </BeginSt= oryboard>

= </Trigger= .EnterActions>

= <Trigger.= ExitActions>

= <BeginSto= ryboard>

= <Storyboa= rd>

= <DoubleAn= imation Storyboard.TargetProperty=3D"Opacity"

= To=3D"0.25" Duration=3D&qu= ot;0:0:1" />

= </Storybo= ard>

= </BeginSt= oryboard>

= </Trigger= .ExitActions>

= </Trigger= >

</Style.T= riggers>

</Style>

</Grid.Resources>

</Button>

</Grid>

<= /span>

Where this gets ev= en more interesting is with DataTriggers. You can imagi= ne databinding to a web service for example and, if a ce= rtain value was returned by the web service, an animation could be triggered.

<= /span>

Also, using MultiTriggers and MultiDataTrigg= ers would allow these animations to be conditionally begun based on more than o= ne property or data value.

<= /span>

Improved = 3D Databinding

DataBinding can only target D= ependencyProperties. In order to enable scenarios like databinding t= he height of a bar in a bar graph to the Y scale of a ScaleTransform3D, the X/= Y/Z are now properties that are separate DependencyPropert= ies of type double. This is consistent with the existing Offset, Scale, a= nd Skew in 2D transforms and with most other DependencyPr= operties in Avalon.

Old	New
TranslateTransform3D.Offset	TranslateTransform3D.OffsetX TranslateTransform3D.OffsetY TranslateTransform3D.OffsetZ
ScaleTransform3D.Scale<= o:p> ScaleTransfrom3D.Center=	ScaleTransform3D.ScaleX ScaleTransform3D.ScaleY ScaleTransform3D.ScaleZ ScaleTransform3D.CenterX ScaleTransform3D.CenterY ScaleTransform3D.CenterZ<= /o:p>
RotateTransform3D.Center	RotateTransform3D.CenterX RotateTransform3D.CenterY RotateTransform3D.CenterZ=
ScaleTransform.Center	ScaleTransform.CenterX ScaleTransform.CenterY
SkewTransform.Center	SkewTransform.CenterX SkewTransform.CenterY
RotateTransform.Center	RotateTransform.CenterX RotateTransform.CenterY

Here is an example of the types of databinding that = can now be done with this new syntax. The sample binds a slider control to the Offset= X of the translation and the ScaleY of the scale.= It also shows how the 3D engine now supports databinding, in this case it databinds to the value of an XML datasource using the VisualBrush. Databinding is enabled by the use of the ModelVisual3D construct, which is detailed in the= breaking changes below.

&l= t;Grid xm= lns=3D"http:/= /schemas.microsoft.com/winfx/avalon/2005"

&nbs= p; xmlns:x=3D"http://schemas.microsoft.com/winfx/xaml/2005&qu= ot;>

&nbs= p; <Grid.Resources>

<Setter Pr= operty =3D "Value<= /span>" Value =3D"1&q= uot;/>

</Style>

= <text>TEXT.</text>

</data>

</XmlDat= aProvider>

<MeshGeometry3D x:Key=3D"meshData" =

= Positions=3D"-1 -1 0 = 1 -1 0 -1 1 0 1 1 0"

= Normals=3D"0 0 1 0 = 0 1 0 0 1 0 0 1"

= TextureCoordinates=3D"0 1 1 1<= span style=3D'mso-spacerun:yes'> 0 0 1 0 "= ;

= TriangleIndices=3D"0 1 2 1 = 3 2" />

&nbs= p; </Grid.Resources>

&nbs= p; <StackPanel = Orientation=3D"Horizontal">=

<Label>Translate OffsetX</= Label>

<Slider Wi= dth=3D"100" Style=3D"{StaticReso= urce Horizontal}" Name=3D"<= span style=3D'color:blue'>sliderOffsetX"/= >

<Label>Scale ScaleY</L= abel>

<Slider Wi= dth=3D"100" Style=3D"{StaticReso= urce Horizontal}" Name=3D"<= span style=3D'color:blue'>sliderScaleY"/&= gt;

&nbs= p; </StackPanel>

&nbs= p; <Grid>

= <ModelVisual3D.Content&= gt;

= <Model3DGroup >

= <Model3DGroup.Children&= gt;

= <DirectionalLight = Color=3D"#FFFFFFFF" Direction=3D&q= uot;-3,-4,-5" />=

= <GeometryModel3D = Geometry=3D"{StaticResource meshData}">

= <GeometryModel3D.Material>

= <DiffuseMaterial>

= &l= t;DiffuseMaterial.Brush>

= &nb= sp; <VisualBrush >

= &nb= sp; <VisualBrush.Visual&= gt;

= &nb= sp; <TextBlock = Text=3D"{Binding Source=3D{StaticResource ImageData}, XPath=3D= data/text}" >

= = </TextBlock>

= &nb= sp; </VisualBrush.Visual<= span style=3D'font-size:10.0pt;font-family:Verdana;mso-bidi-font-family:"Courier= New"; color:blue'>>

= &nb= sp; </VisualBrush>

= &nb= sp; </DiffuseMaterial.Brush>

= </DiffuseMaterial>

= </GeometryModel3D.Material>

= <= GeometryModel3D.Transform>

= <Transform3DGroup>

= &nb= sp; <ScaleTransform3D = ScaleX=3D"1" ScaleY=3D"= ;{Binding ElementName=3DsliderScaleY, Path=3DValue}" ScaleZ=3D"1&qu= ot;/>

= &nb= sp; <TranslateTransform3D = OffsetX=3D"{Binding ElementName=3DsliderOffsetX, Path=3DValue}" OffsetY=3D"-0&q= uot; OffsetZ=3D"1&qu= ot;>

= &nb= sp; </TranslateTransform3D>

= &nb= sp; <RotateTransform3D&= gt;

= &nb= sp; <RotateTransform3D.Rotation>

= &nb= sp; <AxisAngleRotation3D<= span style=3D'mso-spacerun:yes'> Axis=3D"0,3,0<= /span>" Angle=3D"45&q= uot; />

= &nb= sp; </RotateTransform3D.Rotation= >

= &nb= sp; </RotateTransform3D>

= </Transform3DGroup>

= </GeometryModel3D.Transform<= /span>>

= </GeometryModel3D>

= </Model3DGroup.Children>

= </Model3DGroup>

= </ModelVisual3D.Content>

</ModelVisual3D>

<Viewport3D.Camera>

= <PerspectiveCamera = FarPlaneDistance=3D"20" U= pDirection=3D"0,1,0" NearPlaneDistance=3D"1&qu= ot; Position=3D"0,0,10" FieldOfView=3D"45&q= uot; />

</Viewport3D.Camera>

</Viewport3D>

&nbs= p; </Grid>

&l= t;/Grid>

<= /span>

Breaking = Changes

<= /span>

Mini-Language Removal

The formats bein= g removed are:

1. "HorizontalGradie= nt color1 color2"

2. "VerticalGradient= color1 color2"

3. "LinearGradient x1,y1 x2,y2 color1 color2"

4. "RadialGradient color1 color2"

5. "Image filename.e= xtension"

6. the entire trans= form mini-language ("scale(1,2) rotate(45) ...")<= /p>

For reference:

Becomes

<Rectangle.Fill>

<LinearGradientBrush.GradientStops>

<GradientStop Offset=3D”0” Color=3D”color1”/>=

<GradientStop Offset=3D”1” Color=3D”color2”/>=

</GradientStopCollection>

</LinearGradientBrush.GradientStops>

</LinearGradient>

</Rectangle.Fill>

</Rectangle>

VerticalGradient is similar R= 11; just change EndPoint to “0,1”, and LinearGradient simply sets StartPoint to x1,y1 and EndPoint to x2,y2. For RadialGradient, the default values for Center and Rad= ii are used, so you needn’t set them, similarly for Ima= geBrush – all values are default except Source=3D”= filename.extension”.

For Transforms, = you convert a string like “scale(1,2) rotate(4= 5)…” to

<TransformGroup&= gt;

<TransformGroup.Children><= /span>

</TransformGroup.Children>=

</TransformGroup>

The existing min= i-language for Matrix replaces the Transform language - that is, 6 doubles which repre= sent m11, m12, m21, m22, offsetX= , offsetY in an affine transform or “Identity”.

There is a tool available in the download associated with this article that will ease the p= ain in porting your code to this new syntax.&n= bsp;

Removal of ~ (Tilde) syn= tax

WPF has removed support for ~/ used in rela= tive Uris. Subsequent to this change, you will have = to use the Pack Uri syntax in order to reference files at site of origin. For inst= ance, <Image Source=3D”~/foo.jpg” /> changes to <Image Source=3D”pack://site= oforigin:,,,/foo.jpg” />

Removal of WebServiceDataProvider and changes to ObjectDa= taProvider

WebServiceDataSource is being deprecated, and its functionality is being merged into ObjectDataSource.&nb= sp; ObjectDataProvider will no longer take <= span class=3DSpellE>TypeName, but instead take an Ob= jectType. In addition, = ObjectDataProvider will no longer take Parameters in a string, but instead has parameter collections. Lastly, ObjectDataProvider can accept any object as its ObjectInstance, and will use the Data of a DataSourceProvider that’s assigned to ObjectInstance.

Old way:

<Page>

<Page.Resources>

New way:

<?Mapping XmlNamespace=3D"local" ClrNamespace=3D"System"?>

<?Mapping XmlNamespace=3D"ws" ClrNamespace=3D"Web.Service.Namespace" Assembly=3D"assembly&= quot; ?>

<Page.Resources>

<ObjectDataProvider.ConstructorParameters>

<x:string>some-string</x:string>

<x:I= nt32>2</x:Int32>

</ObjectDataProvider.ConstructorParameters>

</ObjectDataProvider>

.WBA change to .XBAP

The WPF Web Browser Application file extension will change from ‘.wb= a’ to ‘.xbap’ and the MIME content typ= e from ‘application/x-ms-wba’ to ‘application/x-ms-xbap’.

<= /span>

Control Changes

There are several = changes to a number of controls in WPF:

<= /span>

· Replaced TabStripPlacement enum with Dock

· Removed BeginStoryboard.Placeholder even= t

· Renamed DictionaryLocation to ResourceDictionaryLocation (

The System.Windows.Diction= aryLocation enum is being renamed to R= esourceDictionaryLocation.

Any ThemeInfoAttributes will need to be modified:

Old:

[ThemeInfoAttribute(DictionaryLocation.*, DictionaryLocation.*)]

New:

[ThemeInfoAttribute(ResourceDictionaryLocation.*, ResourceDictionaryLocation.*)]

· Remove Popup.HasDropShadow

HasDropShadow property has been removed from popup.

· Use PART_ names for ScrollBar and make <= span class=3DSpellE>IsStandAlone property Internal <= /span>

Instead of specifying IsSt= andalone=3D”false” on scrollbars in a ScrollViewer’s templat= e, now you should specify one of the following names: P= ART_HorizontalScrollBar or PART_VerticalScrollBar. ScrollBars outside of scrollviewer’s templates will continue to work without modification.

Old:

= ; &n= bsp; <…>

= ; &n= bsp; <ScrollBar Orientation=3D”Horizontal” IsStandalone=3D”= false” …/>

‘ &nbs= p; &= nbsp; &nbs= p; <ScrollBar Orientation=3D”Vertical” IsStandalone=3D”false” …/>

= ; &n= bsp; <…>

= ; &n= bsp; </ControlTemplate>

= ; &n= bsp; <!—Standalone Scrollbar-- >

= ; &n= bsp; <ScrollBar IsStandalone=3D”true”/>

New:

= ; &n= bsp; <…>

= ; &n= bsp; <ScrollBar Orientation=3D”Horizontal” Name=3D”PART_Hor= izontalScrollBar” …/>

‘ &nbs= p; &= nbsp; &nbs= p; <ScrollBar Orientation=3D”Vertical” Name=3D”PART_Verti= calScrollBar” …/>

= ; &n= bsp; <…>

= ; &n= bsp; </ControlTemplate>

= ; &n= bsp; <!—Standalone Scrollbar-- >

= ; &n= bsp; <ScrollBar/>

3D Change= s

<= /span>

The new Chi= ldren collection hanging off of ViewPort3D is of type Visual3Dcollectio= n and the Models collection has been remo= ved. The primary type you will add to this Children collection is the new= ModelVisual3D. ModelVisual3D has a <= b>Content property that takes a Model3D which of course Model3DGroup derives from. This is where all Model3DGroup objects will go, includ= ing lights and geometries. ModelVisual3D also has a Children property of type Visual3DCollection so that additional ModelVisua= l3D objects can be nested. =

In essence, th= is change is an additional layer between the viewpor= t and the models, a visual layer. Daniel Lehenbauer expl= ains in a recent blog post exactly why this additional visual layer was added. He has a relatively deep discussion of the architectural underpinnin= gs that governed the change. =

Two things are= gained from this change:

1. Extensibility. Model3DGroup and GeometryModel3D are sea= led, which meant you couldn't derive from them and create your classes. For example, you couldn’t cr= eate your own cube class that could be instantiated directly in XAML. But = ModelVisual3D is not sealed, so the ability to inherit from it enables the ability to cre= ate your own classes that create reusable models.

2. Databinding. With this change, databinding is directly enabl= ed on properties of 3D objects instead of the indirect datab= inding.

<= /span>

There have been ad= ditional API changes to the 3D API.

<= /span>

The Up property ha= s been renamed UpDirection and the LookAtPoint property will become LookDirection. The type wi= ll be a Vector3D instead of a Point3D. Camera will have a Transform property which transforms the Positon, Lo= okDirection, and UpDirection in the same way Model3D.Transfo= rm affects the position and direction of a SpotLight. This will enable "rotate this camera around the world"-like scena= rios which are impossible to do with Point3D/Vector3D animations alone. This will also enable animations on MatrixCamera which previously always required custom code to animate.

<= /span>

Lastly, Rotation3D= is now abstract and its API is the new AxisAngleRotation3D. In Xaml, this is a pure rename. Use AxisAngleRotation3D where you used to use Rotation3D.

<= /span>

If you interact wi= th 3D rotations from code there a few things you need to be aware of:<= /span>

<= /span>

· The retu= rn result of RotateTransform3D.Rotation is an abstract Rotation3D. You n= eed to cast to AxisAngleRotation3D to get to the Axis/Angle properties.

· The RotationTransform3D ctor which tacks an axis/an= gle has been removed, instead use new RotateTransform3D(new AxisAngleRotation3D(axis, angle)).

· The Rotation3D.Quaternion property has been removed, you can construct a Quater= nion via new Quaternion(aarot.Ax= is, aarot.Angle).

<= /span>

Change to Visuals

VisualTreeHelper (formerly VisualOperations) now serves only as a public “Getter” class and no longer provide “SetR= 21; methods.

Media Change= s

There have been some fundamental changes to the way audio and video is played in WPF. A new object has been introduced, = called the MediaPlay= er. The MediaPlayer object can be = used in two different modes, depending on what is driving the player: Independent mode or Clock mode. When used= in the Independent mode, the MediaPlayer object does not use the WPF timing system and directly plays the media. In = Clock mode, the Med= iaPlayer can be thought of as a target for an animation, and thus it will have corresponding Timeline and Clock entries in the timing tree. Clock mode is useful if the media = needs to be synched with other timelines; if no synching needs to occur, the over= head of creating a clock is not necessary and independent mode is sufficient.

The MediaPla= yer.Clock property determines in which mode the player is: null implies Independent m= ode; non-null implies Clock mode. =

The MediaElement is still in t= he API and is link between the MediaPlayer and the WPF framework, handling tasks like layout and composition of the ac= tual media. The relationship betwe= en MediaPlayer and MediaElement is as follows: A MediaPlayer may be associated with a MediaElement, but a MediaElement always has an underlying MediaPlayer.

The MediaClo= ck and MediaTimeline only have relevance if the MediaPlayer is used in Clock mode. They derive from the WPF animation system and work like all clocks and timelines, in that the timeline is a template for the clock; it is the MediaClock, i= f used, that actually drives the Me= diaPlayer.

The MediaPla= yer is in Independent mode by default, but there are two ways to switch into Cl= ock mode:

1. Inside of a Storyboard, when a= MediaTimeline is targeted at a M= ediaElement, a MediaClock will be created and assigned to th= e MediaElement’s associated player;
2. By explicitly creating a MediaC= lock from a MediaTimeline and assigning it to a MediaPlayer object.

There are a few control options t= hat are only available in Independent mode:
- Seting a MediaPlayer.Sou= rce;
- Using the Play, Pause, and Stop methods on MediaPlay= er;
- Changing MediaPlayer’s Position and SpeedRatio properties.

If the user attempts to use these features while in Clock mode, an InvalidOperationExcep= tion will be thrown. In this case,= the Timing engine controls must be used for manipulating the media. =

Setting the source of the media b= eing played differs between independent mode and clock mode. This can be confusing, because the= re is a Source property on MediaElement, MediaPlayer= and MediaTimeline. =

In independent mode, the source c= an be set on either the MediaElement or the MediaPlayer. A change in MediaEl= ement.Source will be reflected in MediaElement.Player.Source= and vice-versa. Setting the sourc= e on MediaElement will immediately begin playing the audio/video; setting the source on the MediaPlayer, however, requires that media is actually started.

In clock mode, the source of the = media must be set in the MediaTimeline. This has the effect of setting the source on the MediaPlayer. Note that the media = will not start playing until the clock is assigned to a Med= iaPlayer.

Some code samples should help elu= cidate the new model:

Basic XAML Scenario

<= /span>

This would create = a MediaPlayer, set the Source on the MediaElement, which sets MediaElement.Player.Source, which in= turn will start to load the Media and play it.

<= /span>

<Canvas xmlns=3D"http://schemas.microsoft.com/winfx/avalon/2005" xmlns:x=3D"http://schemas.microsoft.com/winfx/xaml/2005">=

</Canvas>

<= /span>

Storyboard XAML Scenario=

<= /span>

In this case, the = MediaElement does not have a pre-specified Source. MediaElement.= Player would still be created at load time, but with an empty Source. At BeginStory= board, a MediaClock would be created on the MediaTimeline automatically, and it would be set onto= myvideo.Player.Clock. Setting MediaPlayer.Clock also has the e= ffect of setting MediaPlayer.Source.

<= /span>

<Canvas xmlns=3D"http://schemas.microsoft.com/winfx/avalon/2005" xmlns:x=3D"http://schemas.microsoft.com/winfx/xaml/2005">=

<Canvas.Triggers>=

<EventTrigger RoutedEvent=3D"Button.Click" SourceName=3D"playButton"&= gt;

<EventTrigger.Actions>

= <Storyboard>

= <MediaTimeline Source=3D"ep2.wmv" Storyboard.TargetName=3D"myvideo"/>

= </Storyboard>

</BeginStoryboard>

</EventTrigger.Actions>

</EventTrigger><= o:p>

<EventTrigger.Actions>

</EventTrigger.Actions>

</EventTrigger><= o:p>

</Canvas.Triggers>

<Button Name=3D"pauseButton" >Pause</Button>

</StackPanel>

</Canvas>

Under the new APIs= , preroll can be achieved through code by setting MPs.Source to the desired Uri. This can be done at page loaded, f= or example. Once a BeginStoryboard is called and ME.Player.Source is set, the MP w= ould know that it’s the same Uri and would retain the opened file.

<= /span>

Audio Scenario

<= /span>

<Canvas xmlns=3D"http://schemas.microsoft.com/winfx/avalon/2005" xmlns:x=3D"http://schemas.microsoft.com/winfx/xaml/2005">=

</Canvas>

<= /span>

Changing Volume Properti= es

<= /span>

<Canvas xmlns=3D"http://schemas.microsoft.com/winfx/avalon/2005" xmlns:x=3D"http://schemas.microsoft.com/winfx/xaml/2005">=

</Canvas>

<= /span>

Manipulating MediaElement with Transforms, Clip and Opacity

<= /span>

<Canvas xmlns=3D"http://schemas.microsoft.com/winfx/avalon/2005">=

<MediaElement.LayoutTransform>

</TransformGroup>

</MediaElement.Layo= utTransform>

</MediaElement>

<MediaElement.Clip&= gt;

<EllipseGeometry Center=3D"200,100" RadiusX=3D"150" RadiusY=3D"100" />=

</MediaElement.Clip= >

<MediaElement.LayoutTransform>

<Transf= ormGroup>

<SkewTransform AngleX=3D"15" AngleY=3D"15" /&= gt;

</TransformGroup>

</MediaElement.LayoutTransform>

</MediaElement>

</Canvas>

<= /span>

Audio Scenario Using the Timing Engine

<= /span>

MediaPlayer player;

void startClick(object = sender, RoutedEventArgs e)

{

MediaTimeline mt =3D new MediaTime= line(new Uri("sound.wav"));

MediaClock mc =3D mt.CreateClock()= ;

player.Clock =3D mc; // starts pre= rolling

}

void beginClick(object = sender, RoutedEventArgs e)

{

player.Clock.ClockController.Begin= ();

}

void stopClick(object s= ender, RoutedEventArgs e)

{

player.Clock.ClockController.Stop(= );

}

void pauseClick(object = sender, RoutedEventArgs e)

{

player.Clock.ClockController.Pause= ();

}

void resumeClick(object= sender, RoutedEventArgs e)

{

player.Clock.ClockController.Resum= e();

}

void volumeIncClick(obj= ect sender, RoutedEventArgs e)

{

player.Volume+=3D0.25;<= /span>

}

void volumeDecClick(obj= ect sender, RoutedEventArgs e)

{

player.Volume-=3D0.25;<= /span>

}

<= /span>

Audio Scenario Without Using the Timing Engine=

<= /span>

MediaPlayer player;

void startClick(object = sender, RoutedEventArgs e)

{

player.Clock =3D null; // this wil= l ensure no clocks are driving this player

player.Source =3D new Uri("sound.wav"); // starts prerolling

}

void beginClick(object = sender, RoutedEventArgs e)

{

player.Position =3D 0; =

player.Play();

}

void stopClick(object s= ender, RoutedEventArgs e)

{

player.Stop();

}

void pauseClick(object = sender, RoutedEventArgs e)

{

player.Pause();<= /p>

}

void resumeClick(object= sender, RoutedEventArgs e)

{

player.Play();

}

void volumeIncClick(obj= ect sender, RoutedEventArgs e)

{

player.Volume+=3D0.25;<= /span>

}

void volumeDecClick(obj= ect sender, RoutedEventArgs e)

{

player.Volume-=3D0.25;<= /span>

}

<= /span>

Creating a Drawing Using= the Timing Engine

<= /span>

Video can also be = used in a Drawing, which can then be used in a DrawingBrush. This is an example where a MediaPlayer is used with out a M= ediaElement.

<= /span>

private static Drawing MakeVideo()

{

MediaTimeline mt =3D new MediaTime= line(new Uri(“ep.wmv”));

MediaClock mc =3D mt.CreateClock()= ;

MediaPlayer mp =3D new MediaPlayer= ();

mp.Clock =3D mc;=

DrawingGroup dg =3D new DrawingGro= up();

using (DrawingContext ctx =3D dg.O= pen())

{

ctx.DrawVideo(mp, new Rect(0, 0, 500, 30));

}

return dg;

}

<= /span>

Creating a Drawing Without Using the Timing Engine=

<= /span>

Video can also be = used in a Drawing, which can then be used in a DrawingBrush.

<= /span>

private static Drawing MakeVideo()

{

MediaPlayer mp =3D new MediaPlayer= ();

mp.Source =3D new Uri(“ep.wmv”);

DrawingGroup dg =3D new DrawingGro= up();

using (DrawingContext ctx =3D dg.O= pen())

{

ctx.DrawVideo(mp, new Rect(0, 0, 500, 30));

}

return dg;

}

<= /span>

Creating a VisualBrush

<= /span>

<Canvas xmlns=3D"http://schemas.microsoft.com/winfx/avalon/2005">=

<Button Height=3D"300" Width=3D"500">=

<Button.Background&= gt;

<VisualBrush.Visual>

= <MediaElement Source=3D"ep2.wmv" />

</VisualBrush.Visual>

</VisualBrush>

</Button.Background= >

</Button><= /p>

</Canvas>

<= /span>

HitTesting Changes

2D Changes

Old	New
HitTestFilter	HitTestFilterCallback<= /o:p>
HitTestResultDelegate<= /o:p>	HitTestResultCallback<= /o:p>
HitTestResult.Visual<= /o:p>	HitTestResult.VisualHit
PointHitTestResult.Point	PointHitTestResult.PointHit
GeometryHitTestResult.Geometry	(Use transform services and/or VisualOperations.GetTransform() to transform the hit testing geometry.)

3D Changes

Old	New
Ray3DHitTestResult	RayHitTestResult

All of the above changes are purely renames without any change= in behavior except for the removal of the GeometryHitTestResult.Ge= ometry API. This property used to return the hit testing geometry transformed into the local space of the hit visual.&nb= sp; There are still two ways to get this information with the Visual API= :

1) Use Tr= ansformToAncestor(hitVisual, startVisual), attempt cast to MatrixTransform and apply resul= t to your hit geometry. This method will include the transforms applied by= ImageEffects. However if you have an ImageEffect applied with a non-linear transformation = the cast may fail.

2) Walk Visual parents from h= itVisual to startVisual concatenating the Visual transforms. This approach ignores ImageEffects.

ItemsControl Changes

Description

A plain ItemsControl (as oppo= sed to a derived class like ListBox) now generates containers of type ContentPresenter, not ContentControl. Some consequences:

The ItemContainerStyle (if any) must specify a targe= t type of ContentPresenter, and the properties na= med in its setters must be applicable to ContentPresente= r.
Any code that w= alks the visual tree looking for a ContentControl should be changed to look for a ContentPresenter<= /span> instead. <= o:p>

Typography C= hanges to Subscript and Superscipt

Removal of Subscript and Superscript Elements

Old:

<Superscript>Hello</Superscript>

<Subscript>Hello&= lt;/Subscript>

New:

<Span Typography.Variants=3D"Superscript">Hello</Span>

<Span Typography.Variants=3D"Subscript">Hello</Span>

Menu Changes=

There have been some basic change= s to the MenuItems:

<MenuItem Mode=3D”Separator” /> is replaced with <Separator />

<MenuItem Mode=3D”Checkable” /> is replaced with <MenuItem IsCheckable=3D”true” />

DocumentStructures Changes

Break was renamed to StoryBreak

Figure was renamed to FigureStructure

List was renamed to ListStructure

ListItem was renamed to ListItemStructure

Paragraph was renamed to ParagraphStructure

Section was renamed to SectionStructure

Table was renamed to TableStructure

TableCell was renamed to TableCellStructure

TableRow was renamed to TableRowStructure

TableRowGrou= p was renamed to TableRowGroupStructure

Removal of <= /span>MonthCalenda= r and DatePic= ker

The MonthCalendar and DatePicker controls have been deprecated.

TimeManager removed

The TimeMana= ger has been removed. =

Acknowled= gements

Thanks to Adam Smith for the mini-language fix tool, the Avalon animation team for the CompositionTarget samples and the Avalon media team for the media samples.<= /p>

<= /span>

Introducing the November CTP: What’s New In Windows Presentation Foundat= ion

Exploring= New Features <= /span>

CompositionTarget=

PropertyTriggers<= /span>

Improved = 3D Databinding

Removal of WebServiceDataProvider and changes to ObjectDa= taProvider

Change to Visuals

Media Change= s

Manipulating MediaElement with Transforms, Clip and Opacity

Audio Scenario Without Using the Timing Engine=

Creating a Drawing Without Using the Timing Engine=

Creating a VisualBrush

HitTesting Changes

ItemsControl Changes

Typography C= hanges to Subscript and Superscipt

DocumentStructures Changes

Removal of <= /span>MonthCalenda= r and DatePic= ker

TimeManager removed

Exploring= New Features
<= /span>