Working with elements in XAML Designer

Artikel
11/15/2016

Note

This article applies to Visual Studio 2015. If you're looking for the latest Visual Studio documentation, see Visual Studio documentation. We recommend upgrading to the latest version of Visual Studio. Download it here

You can add elements—controls, layouts, and shapes—to your app in XAML, in code, or by using XAML Designer. This topic describes how to work with elements in XAML Designer in Visual Studio or Blend for Visual Studio.

Adding an element to a layout

Layout is the process of sizing and positioning elements in a UI. To position visual elements, you must put them in a layout Panel. A Panel has a child property which is a collection of FrameworkElement types. You can use various Panel child elements, such as Canvas, StackPanel, and Grid, to serve as layout containers and to position and arrange the elements on a page.

By default, a Grid panel is used as the top-level layout container within a page or form. You can add layout panels, controls, or other elements within the top-level page layout.

To add an element to a layout

In XAML Designer, do one of the following:
- Double-click an element in the Toolbox (or select an element in the Toolbox and press Enter).
- Drag an element from the Toolbox to the artboard.
- In the Toolbox, select one of the drawing tools (for example, Ellipse or Rectangle), and then draw an element in the active panel.

Changing the layering order of elements

When there are two elements on the artboard in XAML Designer, one element will appear in front of the other in the layering order. At the bottom of the list of elements in the Document Outline window is the front-most element (except for when the ZIndex property for an element is set). When you insert an element into a page, form, or layout container, the element is automatically placed in front of other elements in the active container element. To change the order of elements, you can use the Order commands or drag the elements in the object tree in the Document Outline window.

To change the layering order

Do one of the following:
- In the Document Outline window, drag the elements up or down to create the desired layering order.
- Right-click the element in the Document Outline window or the artboard for which you want to change the layering order, point to Order, and then click one of the following:
  - Bring to Front to bring the element all the way to the front of the order.
  - Bring Forward to bring the element forward one level in the order.
  - Send Backward to send the element back one level in the order.
  - Send to Back to send the element all the way to the back of the order.
  Change the ZIndex property in the Layout section in the Properties window. For overlapping elements, the ZIndex property takes precedence over the order of elements shown in the Document Outline window. An element that has a lower ZIndex value appears in front when elements overlap.

Changing the alignment of an element

You can align elements in the artboard by using menu commands or by dragging elements to snaplines.

A snapline is a visual cue that helps you align an element relative to other elements in the app.

Select the elements that you want to align. You can select more than one element by pressing and holding the Ctrl key while you select the elements.
Select one of the following properties under HorizontalAlignment in the Layout section of the Properties window: Left, Center, Right, or Stretch.
Select one of the following properties under VerticalAlignment in the Layout section of the Properties window: Top, Center, Bottom, or Stretch.

To align two or more elements by using snaplines

In XAML Designer, in a layout that contains at least two elements, drag or resize one of the elements so that the edge is aligned with another element.

When the edges are aligned, an alignment boundary appears to indicate alignment. The alignment boundary is a red dashed line. Alignment boundaries appear only when snapping to snaplines is enabled. For an illustration of the artboard that shows an alignment boundary, see Creating a UI by using XAML Designer.

Changing the an element's margins

The margins in XAML Designer determine the amount of empty space that is around an element on the artboard. For example, margins specify the amount of space between the outside edges of an element and the boundaries of a Grid panel that contains the element. Margins also specify the amount of space between elements that are contained in a StackPanel.

To change an element's margins in the Properties window

Select the element whose margins you want to change.
Under Layout in the Properties window, change the value (in pixels or device-independent units, which are approximately 1/96 inch) for any of the Margin properties (Top, Left, Right, or Bottom).

To change an element's margins in the artboard

To change the margins of an element relative to its layout container, click the margin adorners that appear around the element in the artboard when the element is selected and is within a layout container. For an illustration that shows margin adorners, see Creating a UI by using XAML Designer.

If a margin adorner is open, vertically or horizontally, that margin isn't set. If a margin adorner is closed, that margin is set.

When you open a margin adorner and the opposite margin isn't set, the opposite margin is set to the correct value according to the location of the element in the artboard. For opposite margins, such as the Left and Right margins, at least one property is always set.

Important

Elements placed inside some layout containers, such as a Canvas, don't have margin adorners. Elements placed inside a StackPanel have margin adorners for either the left and right margins or the top and bottom margins, depending on the orientation of the StackPanel.

Grouping and ungrouping elements

Grouping two or more elements in XAML Designer creates a new layout container and places those elements within that container. Placing two or more elements together in a layout container enables you to easily select, move, and transform the group as if the elements in that group were one element. Grouping is also useful for identifying elements that are related to each other in some way, such as the buttons that make up a navigation element. When you ungroup elements, you are simply deleting the layout container that contained the elements.

To group elements into a new layout container

Select the elements that you want to group. (To select multiple elements, press and hold the Ctrl key while you click them.)
Right-click the selected elements, point to Group Into, and then click the type of layout container in which you want the group to reside.

Tip

If you select Viewbox, Border, or ScrollViewer to group your elements, the elements are placed in a new Grid panel within the Viewbox, Border, or ScrollViewer. If you ungroup elements in one of these layout containers, only the Viewbox, Border, or ScrollViewer is deleted, and the Grid panel remains. To delete the Grid panel, ungroup the elements again.

To ungroup elements and delete the layout

Right-click the group that you want to ungroup and click Ungroup.

You can also group or ungroup elements by right-clicking selected items in the Document Outline window and clicking Group Into or Ungroup.

Resetting the element layout

You can restore default values for specific layout properties of an element by using the Layout Reset commands. By using this command, you can reset the margin, alignment, width, height, and size of an element, either individually or collectively.

To reset the element layout

In the Document Outline window or the artboard, right-click the element, choose Layout, Reset PropertyName, where PropertyName is the property that you want to reset (or choose Layout, Reset All to reset all the layout properties for the element).

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