แก้ไข

แชร์ผ่าน


ActivityDesignerPaint.DrawImage Method

Definition

Draws an image on the activity designer surface.

Overloads

DrawImage(Graphics, Image, Rectangle, DesignerContentAlignment)

Draws an image on the activity designer surface by using a Graphics, an Image, a Rectangle, and a DesignerContentAlignment.

DrawImage(Graphics, Image, Rectangle, Rectangle, DesignerContentAlignment, Single, Boolean)

Draws an image on the activity designer surface by using a Graphics, an Image, a source and destination Rectangle, an DesignerContentAlignment, a single-precision floating-point number, and a Boolean value.

DrawImage(Graphics, Image, Rectangle, DesignerContentAlignment)

Draws an image on the activity designer surface by using a Graphics, an Image, a Rectangle, and a DesignerContentAlignment.

public:
 static void DrawImage(System::Drawing::Graphics ^ graphics, System::Drawing::Image ^ image, System::Drawing::Rectangle destination, System::Workflow::ComponentModel::Design::DesignerContentAlignment alignment);
public static void DrawImage (System.Drawing.Graphics graphics, System.Drawing.Image image, System.Drawing.Rectangle destination, System.Workflow.ComponentModel.Design.DesignerContentAlignment alignment);
static member DrawImage : System.Drawing.Graphics * System.Drawing.Image * System.Drawing.Rectangle * System.Workflow.ComponentModel.Design.DesignerContentAlignment -> unit
Public Shared Sub DrawImage (graphics As Graphics, image As Image, destination As Rectangle, alignment As DesignerContentAlignment)

Parameters

graphics
Graphics

The Graphics on which to draw the image.

image
Image

The Image to draw.

destination
Rectangle

The Rectangle that defines the bounds of the image to draw.

alignment
DesignerContentAlignment

The DesignerContentAlignment that specifies how the image is aligned in the bounding rectangle.

Exceptions

graphics, image, or destination contains a null reference (Nothing in Visual Basic).

Examples

The following example demonstrates a way to use the ActivityDesignerPaint class to draw a custom activity on the workflow design surface. A rounded rectangle is first drawn using the DrawRoundedRectangle method. Text is then drawn using DrawText and is placed at the location of the TextRectangle of the ActivityDesigner. Additionally, the Image associated with the ActivityDesigner is drawn using the DrawImage method of the ActivityDesignerPaint class. Finally, an expand button used by a CompositeActivity is drawn using the DrawExpandButton.

private bool expanded = true;
private bool useBasePaint = false;

public bool UseBasePaint
{
    get { return this.useBasePaint; }
    set { this.useBasePaint = value; }
}

public bool Expanded
{
    get { return this.expanded; }
    set { this.expanded = value; }
}

protected override void OnPaint(ActivityDesignerPaintEventArgs e)
{
    if (this.UseBasePaint)
    {
        base.OnPaint(e);
        return;
    }

    DrawCustomActivity(e);
}

private void DrawCustomActivity(ActivityDesignerPaintEventArgs e)
{
    Graphics graphics = e.Graphics;

    CompositeDesignerTheme compositeDesignerTheme = (CompositeDesignerTheme)e.DesignerTheme;

    ActivityDesignerPaint.DrawRoundedRectangle(graphics, compositeDesignerTheme.BorderPen, this.Bounds, compositeDesignerTheme.BorderWidth);

    string text = this.Text;
    Rectangle textRectangle = this.TextRectangle;
    if (!string.IsNullOrEmpty(text) && !textRectangle.IsEmpty)
    {
        ActivityDesignerPaint.DrawText(graphics, compositeDesignerTheme.Font, text, textRectangle, StringAlignment.Center, e.AmbientTheme.TextQuality, compositeDesignerTheme.ForegroundBrush);
    }

    System.Drawing.Image image = this.Image;
    Rectangle imageRectangle = this.ImageRectangle;
    if (image != null && !imageRectangle.IsEmpty)
    {
        ActivityDesignerPaint.DrawImage(graphics, image, imageRectangle, DesignerContentAlignment.Fill);
    }

    ActivityDesignerPaint.DrawExpandButton(graphics,
        new Rectangle(this.Location.X, this.Location.Y, 10, 10),
        this.Expanded,
        compositeDesignerTheme);
}
Private expandedValue As Boolean = True
Private useBasePaintValue As Boolean = False

Public Property UseBasePaint() As Boolean
    Get
        Return Me.useBasePaintValue
    End Get

    Set(ByVal value As Boolean)
        Me.useBasePaintValue = value
    End Set
End Property

Public Property Expanded() As Boolean
    Get
        Return Me.expandedValue
    End Get
    Set(ByVal value As Boolean)
        Me.expandedValue = value
    End Set
End Property


Protected Overrides Sub OnPaint(ByVal e As ActivityDesignerPaintEventArgs)
    If Me.UseBasePaint = True Then
        MyBase.OnPaint(e)
        Return
    End If

    DrawCustomActivity(e)
End Sub

Private Sub DrawCustomActivity(ByVal e As ActivityDesignerPaintEventArgs)
    Dim graphics As Graphics = e.Graphics

    Dim compositeDesignerTheme As CompositeDesignerTheme = CType(e.DesignerTheme, CompositeDesignerTheme)

    ActivityDesignerPaint.DrawRoundedRectangle(graphics, compositeDesignerTheme.BorderPen, Me.Bounds, compositeDesignerTheme.BorderWidth)

    Dim text As String = Me.Text
    Dim TextRectangle As Rectangle = Me.TextRectangle
    If Not String.IsNullOrEmpty(text) And Not TextRectangle.IsEmpty Then
        ActivityDesignerPaint.DrawText(graphics, compositeDesignerTheme.Font, text, TextRectangle, StringAlignment.Center, e.AmbientTheme.TextQuality, compositeDesignerTheme.ForegroundBrush)
    End If

    Dim Image As System.Drawing.Image = Me.Image
    Dim ImageRectangle As Rectangle = Me.ImageRectangle
    If Image IsNot Nothing And Not ImageRectangle.IsEmpty Then
        ActivityDesignerPaint.DrawImage(graphics, Image, ImageRectangle, DesignerContentAlignment.Fill)
    End If

    ActivityDesignerPaint.DrawExpandButton(graphics, _
        New Rectangle(Me.Location.X, Me.Location.Y, 10, 10), _
        Me.Expanded, _
        compositeDesignerTheme)
End Sub

Remarks

When you use this version of DrawImage, the source rectangle is set to the size, in pixels, of the image, the transparency setting is set to 1.0f, and drawing grayscales is not allowed.

Applies to

DrawImage(Graphics, Image, Rectangle, Rectangle, DesignerContentAlignment, Single, Boolean)

Draws an image on the activity designer surface by using a Graphics, an Image, a source and destination Rectangle, an DesignerContentAlignment, a single-precision floating-point number, and a Boolean value.

public:
 static void DrawImage(System::Drawing::Graphics ^ graphics, System::Drawing::Image ^ image, System::Drawing::Rectangle destination, System::Drawing::Rectangle source, System::Workflow::ComponentModel::Design::DesignerContentAlignment alignment, float transparency, bool grayscale);
public static void DrawImage (System.Drawing.Graphics graphics, System.Drawing.Image image, System.Drawing.Rectangle destination, System.Drawing.Rectangle source, System.Workflow.ComponentModel.Design.DesignerContentAlignment alignment, float transparency, bool grayscale);
static member DrawImage : System.Drawing.Graphics * System.Drawing.Image * System.Drawing.Rectangle * System.Drawing.Rectangle * System.Workflow.ComponentModel.Design.DesignerContentAlignment * single * bool -> unit
Public Shared Sub DrawImage (graphics As Graphics, image As Image, destination As Rectangle, source As Rectangle, alignment As DesignerContentAlignment, transparency As Single, grayscale As Boolean)

Parameters

graphics
Graphics

The Graphics on which to draw the image.

image
Image

The Image to draw.

destination
Rectangle

The Rectangle that defines the bounds of the image.

source
Rectangle

The Rectangle that defines the source of the image.

alignment
DesignerContentAlignment

The DesignerContentAlignment that specifies how the image is aligned in the bounding rectangle.

transparency
Single

A single-precision floating-point number that defines the transparency settings for the image.

grayscale
Boolean

true to draw the image in grayscales; otherwise, false.

Exceptions

graphics, image, destination, or source contains a null reference (Nothing in Visual Basic).

-or-

transparency is less than 0, or greater than 1.0f.

Applies to