Partager via

  • Article

RadialGradientBrush Class

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Paints an area with a radial gradient. A focal point defines the beginning of the gradient, and a circle defines the end point of the gradient.

Inheritance Hierarchy

System.Object
  System.Windows.DependencyObject
    System.Windows.Media.Brush
      System.Windows.Media.GradientBrush
        System.Windows.Media.RadialGradientBrush

Namespace:  System.Windows.Media
Assembly:  System.Windows (in System.Windows.dll)

Syntax

'Declaration
Public NotInheritable Class RadialGradientBrush _
    Inherits GradientBrush

public sealed class RadialGradientBrush : GradientBrush

<RadialGradientBrush>
  oneOrMoreGradientStops
</RadialGradientBrush

XAML Values

  • oneOrMoreGradientStops
    One or more GradientStop object elements. Object elements defined here become members of the collection held by the GradientStops property, when accessed by code at runtime.

The RadialGradientBrush type exposes the following members.

Constructors

  Name Description
Public methodSupported by Silverlight for Windows Phone RadialGradientBrush() Initializes a new instance of the RadialGradientBrush class.
Public methodSupported by Silverlight for Windows Phone RadialGradientBrush(GradientStopCollection) Initializes a new instance of the RadialGradientBrush class that has the specified gradient stops.
Public methodSupported by Silverlight for Windows Phone RadialGradientBrush(Color, Color) Initializes a new instance of the RadialGradientBrush class with the specified start and stop colors.

Top

Properties

  Name Description
Public propertySupported by Silverlight for Windows Phone Center Gets or sets the center of the outer circle of the radial gradient.
Public propertySupported by Silverlight for Windows Phone ColorInterpolationMode Gets or sets a ColorInterpolationMode enumeration value that specifies how the gradient's colors are interpolated. (Inherited from GradientBrush.)
Public propertySupported by Silverlight for Windows Phone Dispatcher Gets the Dispatcher this object is associated with. (Inherited from DependencyObject.)
Public propertySupported by Silverlight for Windows Phone GradientOrigin Gets or sets the location of the focal point that defines the beginning of the gradient.
Public propertySupported by Silverlight for Windows Phone GradientStops Gets or sets the brush's gradient stops. (Inherited from GradientBrush.)
Public propertySupported by Silverlight for Windows Phone MappingMode Gets or sets a BrushMappingMode enumeration value that specifies whether the positioning coordinates of the gradient brush are absolute or relative to the output area. (Inherited from GradientBrush.)
Public propertySupported by Silverlight for Windows Phone Opacity Gets or sets the degree of opacity of a Brush. (Inherited from Brush.)
Public propertySupported by Silverlight for Windows Phone RadiusX Gets or sets the horizontal radius of the outer circle of the radial gradient.
Public propertySupported by Silverlight for Windows Phone RadiusY Gets or sets the vertical radius of the outer circle of a radial gradient.
Public propertySupported by Silverlight for Windows Phone RelativeTransform Gets or sets the transformation that is applied to the brush using relative coordinates. (Inherited from Brush.)
Public propertySupported by Silverlight for Windows Phone SpreadMethod Gets or sets the type of spread method that specifies how to draw a gradient that starts or ends inside the bounds of the object to be painted. (Inherited from GradientBrush.)
Public propertySupported by Silverlight for Windows Phone Transform Gets or sets the transformation that is applied to the brush. (Inherited from Brush.)

Top

Methods

  Name Description
Public methodSupported by Silverlight for Windows Phone CheckAccess Determines whether the calling thread has access to this object. (Inherited from DependencyObject.)
Public methodSupported by Silverlight for Windows Phone ClearValue Clears the local value of a dependency property. (Inherited from DependencyObject.)
Public methodSupported by Silverlight for Windows Phone Equals(Object) Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
Protected methodSupported by Silverlight for Windows Phone Finalize Allows an object to try to free resources and perform other cleanup operations before the Object is reclaimed by garbage collection. (Inherited from Object.)
Public methodSupported by Silverlight for Windows Phone GetAnimationBaseValue Returns any base value established for a Silverlight dependency property, which would apply in cases where an animation is not active. (Inherited from DependencyObject.)
Public methodSupported by Silverlight for Windows Phone GetHashCode Serves as a hash function for a particular type. (Inherited from Object.)
Public methodSupported by Silverlight for Windows Phone GetType Gets the Type of the current instance. (Inherited from Object.)
Public methodSupported by Silverlight for Windows Phone GetValue Returns the current effective value of a dependency property from a DependencyObject. (Inherited from DependencyObject.)
Protected methodSupported by Silverlight for Windows Phone MemberwiseClone Creates a shallow copy of the current Object. (Inherited from Object.)
Public methodSupported by Silverlight for Windows Phone ReadLocalValue Returns the local value of a dependency property, if a local value is set. (Inherited from DependencyObject.)
Public methodSupported by Silverlight for Windows Phone SetValue Sets the local value of a dependency property on a DependencyObject. (Inherited from DependencyObject.)
Public methodSupported by Silverlight for Windows Phone ToString Returns a string that represents the current object. (Inherited from Object.)

Top

Fields

  Name Description
Public fieldStatic memberSupported by Silverlight for Windows Phone CenterProperty Identifies the Center dependency property.
Public fieldStatic memberSupported by Silverlight for Windows Phone GradientOriginProperty Identifies the GradientOrigin dependency property.
Public fieldStatic memberSupported by Silverlight for Windows Phone RadiusXProperty Identifies the RadiusX dependency property.
Public fieldStatic memberSupported by Silverlight for Windows Phone RadiusYProperty Identifies the RadiusY dependency property.

Top

Remarks

The RadialGradientBrush is similar to the LinearGradientBrush. However, the linear gradient has a start and an end point to define the gradient vector, while the radial gradient has a ellipse, along with a focal point (the GradientOrigin), to define the gradient behavior. The ellipse defines the end point of the gradient. In other words, a gradient stop at 1.0 defines the color at the ellipse circumference. The focal point defines the center of the gradient. A gradient stop at 0 defines the color at the focal point.

The following image shows a rectangle filled with a radial gradient. The radial gradient that goes from white to gray. The outside circle represents the gradient ellipse while the red dot denotes the focal point. This gradient has its SpreadMethod set to Pad.

Radial gradient with a highlighted focal point

A radial gradient with highlighted components

Examples

In the following example, a radial gradient brush is used to paint the interior of a rectangle.

<StackPanel>
  <!-- This rectangle is painted with a radial gradient. -->
  <Rectangle Width="200" Height="100">
    <Rectangle.Fill>
      <RadialGradientBrush GradientOrigin="0.5,0.5" Center="0.5,0.5"
        RadiusX="0.5" RadiusY="0.5">
        <GradientStop Color="Yellow" Offset="0" />
        <GradientStop Color="Red" Offset="0.25" />
        <GradientStop Color="Blue" Offset="0.75" />
        <GradientStop Color="LimeGreen" Offset="1" />
      </RadialGradientBrush>
    </Rectangle.Fill>
  </Rectangle>
</StackPanel>

The following illustration shows the gradient created in the previous example. The brush's gradient stops have been highlighted. Notice that, even though the results are different, the gradient stops in this example are identical to the gradient stops in the previous linear gradient brush examples.

Gradient stops in a radial gradient

Gradient diagram.

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

Thread Safety

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

See Also

Reference

System.Windows.Media Namespace

LinearGradientBrush

Other Resources

Brushes