ActivityDesigner.OnPaint(ActivityDesignerPaintEventArgs) Metoda

Definicja

Przestrzeń nazw:

System.Workflow.ComponentModel.Design

Zestaw:

System.Workflow.ComponentModel.dll

Rysuje wizualną reprezentację działania w czasie projektowania.

protected:
 virtual void OnPaint(System::Workflow::ComponentModel::Design::ActivityDesignerPaintEventArgs ^ e);

protected virtual void OnPaint (System.Workflow.ComponentModel.Design.ActivityDesignerPaintEventArgs e);

abstract member OnPaint : System.Workflow.ComponentModel.Design.ActivityDesignerPaintEventArgs -> unit
override this.OnPaint : System.Workflow.ComponentModel.Design.ActivityDesignerPaintEventArgs -> unit

Protected Overridable Sub OnPaint (e As ActivityDesignerPaintEventArgs)

Parametry

e

ActivityDesignerPaintEventArgs

Element ActivityDesignerPaintEventArgs zawierający dane zdarzenia.

Wyjątki

ArgumentNullException

ezawiera odwołanie o wartości null (Nothingw Visual Basic).

Przykłady

W poniższym przykładzie pokazano niestandardowy ActivityDesigner , który deleguje odpowiedzialność za obraz do klasy bazowej lub rysuje się na podstawie wartości logicznej. Jeśli useBasePaint jest fałsz, działanie niestandardowe będzie rysować się przy użyciu różnych metod ActivityDesignerPaint klasy.

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