ActivityDesignerPaint.DrawExpandButton 方法

定义

命名空间:

System.Workflow.ComponentModel.Design

程序集:

System.Workflow.ComponentModel.dll

绘制一个用于在活动设计器图面上展开和折叠复合设计器的按钮。

public:
 static void DrawExpandButton(System::Drawing::Graphics ^ graphics, System::Drawing::Rectangle boundingRect, bool drawExpanded, System::Workflow::ComponentModel::Design::CompositeDesignerTheme ^ compositeDesignerTheme);

public static void DrawExpandButton (System.Drawing.Graphics graphics, System.Drawing.Rectangle boundingRect, bool drawExpanded, System.Workflow.ComponentModel.Design.CompositeDesignerTheme compositeDesignerTheme);

static member DrawExpandButton : System.Drawing.Graphics * System.Drawing.Rectangle * bool * System.Workflow.ComponentModel.Design.CompositeDesignerTheme -> unit

Public Shared Sub DrawExpandButton (graphics As Graphics, boundingRect As Rectangle, drawExpanded As Boolean, compositeDesignerTheme As CompositeDesignerTheme)

参数

graphics

Graphics

要在其上绘制按钮的 Graphics。

boundingRect

Rectangle

定义按钮边界的 Rectangle。

drawExpanded

Boolean

要绘制展开的按钮，则为 true；否则为 false。

compositeDesignerTheme

CompositeDesignerTheme

与用于呈现按钮的活动设计器关联的 CompositeDesignerTheme。

例外

ArgumentNullException

graphics 或 compositeDesignerTheme 包含空引用（在 Visual Basic 中为 Nothing）。

示例

下面的示例演示一种使用 ActivityDesignerPaint 类在工作流设计图面上绘制自定义活动的方式。 首先使用 DrawRoundedRectangle 方法绘制一个圆角矩形。 然后使用 DrawText 绘制文本并将其放在 TextRectangle 的 ActivityDesigner 位置。 此外，再使用 Image 类的 ActivityDesigner 方法绘制与 DrawImage 关联的 ActivityDesignerPaint。 最后，使用 CompositeActivity 绘制由 DrawExpandButton 使用的展开按钮。

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 == true)
    {
        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