Visual Studio 2008 support - The Expression Blend 2 December Preview can open and work with Microsoft Visual Studio® 2008 projects and solutions. By default, Windows Presentation Foundation (WPF) projects that are created in the Expression Blend 2 December Preview are now Visual Studio 2008 solutions, whether targeting the Microsoft .NET Framework 3.0 or the .NET Framework 3.5. Visual Studio 2008 solutions cannot be edited in Visual Studio 2005. However, both Expression Blend 2 December Preview and Visual Studio 2005 can still open projects that were created by using earlier versions of Expression Blend and Visual Studio 2005.
Silverlight Support - Silverlight 1.0 projects created in Expression Blend 2 December Preview are now created as website projects instead of application projects, improving interoperability with Visual Studio 2008. Additionally, the Expression Blend user interface has been changed so that only Silverlight 1.0 properties are available; those WPF properties that are unsupported in Silverlight will not be displayed. You can still edit JavaScript-based Silverlight 1.0 projects in Expression Blend 2.
Synchronized File Changes - When editing a Silverlight site project in Expression Blend 2 December Preview and Visual Studio at the same time, any changes that you make in Visual Studio are immediately applied in Expression Blend.
Making Controls from Existing Objects - The Expression Blend 2 December Preview contains new functionality that lets you refactor (in other words, convert) existing content into a control that you can reuse (instantiate). Selected elements, their referenced resources, and referenced animations are refactored into the new control. You must build the project to be able to see and instantiate the new control.
Split View and XAML Editor Improvements - The Expression Blend 2 December Preview lets you view an open document in both Design view and XAML view at the same time by selecting the new Split tab on the right side of the artboard. Changes to your document are immediately reflected in both the Design and XAML windows in Split view, whether the changes are made to objects, Storyboards, styles, templates, keyframes, and so on. Additionally, when you select an object, on the artboard in Design view or under Objects and Timeline, the cursor in XAML view immediately moves to the corresponding line of XAML. You can specify font size, font family, tab size, and word-wrap for the XAML editor (XAML tab) by modifying the Code Editor settings under Options in the Tools menu.
Storyboard Picker - The Storyboard picker replaces the old Storyboard box. The picker consists of a label to indicate the name of the selected Storyboard (if a Storyboard is selected), a shortcut menu (available when you right-click the label), a pop-up button (and resulting pop-up menu), and a Close button to close all Storyboards and exit recording mode. Both the shortcut menu and the pop-up menu let you create a New Storyboard, and if a Storyboard is already selected, you can now Duplicate, Reverse, or Delete the selected Storyboard. The shortcut menu also lets you Rename the selected Storyboard. The pop-up menu contains all Storyboards in scope in a multicolumn layout. You can resize the pop-up menu, and filter its list according to a search text box at the top of the list. The Storyboard label serves as the Storyboard selector when you want to modify properties on a Storyboard.
Storyboard and Keyframe Properties - The Expression Blend 2 December Preview contains new functionality for setting properties on Storyboards and on keyframes in the Properties panel. When you have a Storyboard selected, you can set a property to change the repeat behavior, and to make it reverse when it reaches the end. Note that you can change these properties only after you click the Storyboard label.
Key Spline Editor - When you have one or more keyframes selected in a Storyboard, you can change the easing behavior between keyframes by using the new key spline graphical editor under Easing in the Properties panel. You can drag the endpoints on the graph, or set specific values. On the graph, the x-axis represents the time between the previous keyframe and the one that is selected, and the y-axis represents the value of the property being animated. Modifying the easing behavior can help you develop a more realistic animation. You can reuse key splines by making them into resources and applying them to other keyframes.
Vertex Animation - The Expression Blend 2 December Preview contains new functionality for animating individual vertices (points and tangents) on a line. Previously, if you modified a vertex when in animation recording mode, the original shape of the object was permanently modified. Now, you can animate individual vertices on a path, you can convert between line and Bézier segments, and you can add vertices to an existing animated path.
Clip Path Editing and Animating - Expression Blend 2 December Preview now enables you to modify clipping paths on the artboard after you create them. You can also animate the individual vertices of clipping paths, and you can release a clipping path without losing the original path object.
Breadcrumb Bar - The Expression Blend 2 December Preview now displays a breadcrumb bar above the artboard, which helps you keep track of where you are in a template hierarchy as you navigate through it. The breadcrumb bar also helps you quickly switch editing scopes when you are editing templates and styles in WPF projects. The breadcrumb specifies the selected object. If a template can be applied to the object (such as a button), you can click a drop-down arrow in the breadcrumb item to view the actions that you can perform on the object (such as editing a button template). If you have already edited a style or template on the object, the breadcrumb includes additional items that represent the style and template items that you edited earlier. This makes it easy to see which style or template has already been edited on an object, to quickly switch the scope in which you are editing, and to understand exactly where you are as you make changes.
Font Embedding - The Expression Blend 2 December Preview contains new functionality for embedding fonts in your project. Embedding makes sure that the font that you select for your application is the font that users will see when they run your application. Typically, users will already have most of the fonts that you can select in Expression Blend, and therefore you do not have to embed them. If the user does not have your chosen font, a default system font will appear. If you do decide to embed, subset, or otherwise redistribute fonts in your application, it is your responsibility to make sure that you have the required license rights for those fonts. For the fonts that come with Expression Blend, see the Microsoft Software License Terms (EULA.language.rtf) file for full license terms. For other commercial fonts, see the Microsoft Typography web site for information that can help you locate a particular font vendor or find a font vendor for custom work. To embed fonts in an Expression Blend application, you can use the new Font Embedding manager available in the Tools menu and available in the Advanced Properties section under Text in the Properties panel when you select a text control. For more information about how to embed fonts in WPF applications, see Packaging Fonts with Applications on MSDN.
Build Options - When building inside the Expression Blend 2 December Preview, the property $(BuildingInsideExpressionBlend) is set to true. You can use this property in your project or .targets files to change how the project builds when in Expression Blend. For more information about how Visual Studio supports this scenario, see the Visual Studio Integration documentation.
Copying Projects - You can now create copies of your projects and sites in Expression Blend 2 December Preview by clicking Save Solution Copy on the File menu. These copies are exact replicas of the project or site that you are working on, and saved to disk without leaving the version that you are working on.
Adding Multiple Projects to a Single Solution - When you create a WPF project in Expression Blend 2 December Preview, a solution file is automatically created for you. This solution file is compatible with Visual Studio 2008. In Expression Blend 2 December Preview, you can now add multiple projects to your solution by right-clicking the name of the solution in the Project panel and then clicking Add New Project or Add Existing Project. You can also add references to existing projects (without copying them to your solution) by right-clicking the References folder in the Project panel and then clicking Add Project Reference.
Drag and Drop - It is now possible to incorporate media into your projects by dragging media files from outside Expression Blend 2 December preview and dropping them onto the artboard when a document is open. The media files are automatically added to your project. Additionally, you can drag any supported asset files (3D objects, media files, XAML files) into the Project panel to add them to your project.
Support for New 3D Objects - The .NET Framework 3.5 introduces new 3D objects. Expression Blend 2 December Preview does not include the new 3D objects in the Asset Library. However, you can use them by making modifications manually in XAML, or by using Visual Studio 2008 to add the objects and then open your project in Expression Blend. The new 3D objects are recognized by Blend, and you can use the 3D adorners to adjust those objects in the scene.
Object Manipulation - In Expression Blend 2 December Preview, you can duplicate objects by dragging them while holding the CTRL key. You can also resize, scale, and rotate multiple objects at the same time by selecting them and then using the resizing handles on the artboard. You can also rotate multiple selected objects around any center of rotation.
Keyboard Shortcuts - A number of keyboard shortcuts in Expression Blend 2 December Preview have been updated to be more consistent with the keyboard shortcuts in Microsoft Expression Design.
Close Buttons on Panels - The Project, Properties, and Resources panels now include a close button in the upper-right corner, whether they are floating or fixed. You can open these panels again from the Window menu. You can still use TAB or F4 to toggle all panels at the same time.
Search Text Boxes - The Search label that typically appears next to the search text box in the Properties panel, the Asset Library window, and the new Storyboard picker, now appears inside the search text box. The Search text disappears when the user starts typing keywords into the search text box.
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