ScrollBarRenderer.DrawLeftHorizontalTrack Methode

public:
 static void DrawLeftHorizontalTrack(System::Drawing::Graphics ^ g, System::Drawing::Rectangle bounds, System::Windows::Forms::VisualStyles::ScrollBarState state);

public static void DrawLeftHorizontalTrack(System.Drawing.Graphics g, System.Drawing.Rectangle bounds, System.Windows.Forms.VisualStyles.ScrollBarState state);

static member DrawLeftHorizontalTrack : System.Drawing.Graphics * System.Drawing.Rectangle * System.Windows.Forms.VisualStyles.ScrollBarState -> unit

Public Shared Sub DrawLeftHorizontalTrack (g As Graphics, bounds As Rectangle, state As ScrollBarState)

Parameter

Ausnahmen

Beispiele

Im folgenden Codebeispiel wird die Methode in der DrawLeftHorizontalTrack Methode eines benutzerdefinierten Steuerelements verwendet, um die linke Seite eines Bildlaufleistentitels OnPaint im gedrückten Zustand zu zeichnen. Dieses Codebeispiel ist Teil eines größeren Beispiels, das für die ScrollBarRenderer Klasse bereitgestellt wird.

    // Draw the scroll bar in its normal state.
protected:
    virtual void OnPaint(PaintEventArgs^ e) override
    {
        __super::OnPaint(e);

        // Visual styles are not enabled.
        if (!ScrollBarRenderer::IsSupported)
        {
            this->Parent->Text = "CustomScrollBar Disabled";
            return;
        }

        this->Parent->Text = "CustomScrollBar Enabled";

        // Draw the scroll bar track.
        ScrollBarRenderer::DrawRightHorizontalTrack(e->Graphics,
            ClientRectangle, ScrollBarState::Normal);

        // Draw the thumb and thumb grip in the current state.
        ScrollBarRenderer::DrawHorizontalThumb(e->Graphics,
            thumbRectangle, thumbState);
        ScrollBarRenderer::DrawHorizontalThumbGrip(e->Graphics,
            thumbRectangle, thumbState);

        // Draw the scroll arrows in the current state.
        ScrollBarRenderer::DrawArrowButton(e->Graphics,
            leftArrowRectangle, leftButtonState);
        ScrollBarRenderer::DrawArrowButton(e->Graphics,
            rightArrowRectangle, rightButtonState);

        // Draw a highlighted rectangle in the left side of the scroll
        // bar track if the user has clicked between the left arrow
        // and thumb.
        if (leftBarClicked)
        {
            clickedBarRectangle.X = thumbLeftLimit;
            clickedBarRectangle.Width = thumbRectangle.X - thumbLeftLimit;
            ScrollBarRenderer::DrawLeftHorizontalTrack(e->Graphics,
                clickedBarRectangle, ScrollBarState::Pressed);
        }

        // Draw a highlighted rectangle in the right side of the scroll
        // bar track if the user has clicked between the right arrow
        // and thumb.
        else if (rightBarClicked)
        {
            clickedBarRectangle.X =
                thumbRectangle.X + thumbRectangle.Width;
            clickedBarRectangle.Width =
                thumbRightLimitRight - clickedBarRectangle.X;
            ScrollBarRenderer::DrawRightHorizontalTrack(e->Graphics,
                clickedBarRectangle, ScrollBarState::Pressed);
        }
    }

// Draw the scroll bar in its normal state.
protected override void OnPaint(PaintEventArgs e)
{
    base.OnPaint(e);

    // Visual styles are not enabled.
    if (!ScrollBarRenderer.IsSupported)
    {
        this.Parent.Text = "CustomScrollBar Disabled";
        return;
    }

    this.Parent.Text = "CustomScrollBar Enabled";

    // Draw the scroll bar track.
    ScrollBarRenderer.DrawRightHorizontalTrack(e.Graphics,
        ClientRectangle, ScrollBarState.Normal);

    // Draw the thumb and thumb grip in the current state.
    ScrollBarRenderer.DrawHorizontalThumb(e.Graphics,
        thumbRectangle, thumbState);
    ScrollBarRenderer.DrawHorizontalThumbGrip(e.Graphics,
        thumbRectangle, thumbState);

    // Draw the scroll arrows in the current state.
    ScrollBarRenderer.DrawArrowButton(e.Graphics,
            leftArrowRectangle, leftButtonState);
    ScrollBarRenderer.DrawArrowButton(e.Graphics,
            rightArrowRectangle, rightButtonState);

    // Draw a highlighted rectangle in the left side of the scroll 
    // bar track if the user has clicked between the left arrow 
    // and thumb.
    if (leftBarClicked)
    {
        clickedBarRectangle.X = thumbLeftLimit;
        clickedBarRectangle.Width = thumbRectangle.X - thumbLeftLimit;
        ScrollBarRenderer.DrawLeftHorizontalTrack(e.Graphics,
            clickedBarRectangle, ScrollBarState.Pressed);
    }

    // Draw a highlighted rectangle in the right side of the scroll 
    // bar track if the user has clicked between the right arrow 
    // and thumb.
    else if (rightBarClicked)
    {
        clickedBarRectangle.X =
            thumbRectangle.X + thumbRectangle.Width;
        clickedBarRectangle.Width =
            thumbRightLimitRight - clickedBarRectangle.X;
        ScrollBarRenderer.DrawRightHorizontalTrack(e.Graphics,
            clickedBarRectangle, ScrollBarState.Pressed);
    }
}

' Draw the scroll bar in its normal state.
Protected Overrides Sub OnPaint(ByVal e As PaintEventArgs)
    MyBase.OnPaint(e)

    ' Visual styles are not enabled.
    If Not ScrollBarRenderer.IsSupported Then
        Me.Parent.Text = "CustomScrollBar Disabled"
        Return
    End If

    Me.Parent.Text = "CustomScrollBar Enabled"

    ' Draw the scroll bar track.
    ScrollBarRenderer.DrawRightHorizontalTrack(e.Graphics, _
        Me.ClientRectangle, ScrollBarState.Normal)

    ' Draw the thumb and thumb grip in the current state.
    ScrollBarRenderer.DrawHorizontalThumb(e.Graphics, _
        thumbRectangle, thumbState)
    ScrollBarRenderer.DrawHorizontalThumbGrip(e.Graphics, _
        thumbRectangle, thumbState)

    ' Draw the scroll arrows in the current state.
    ScrollBarRenderer.DrawArrowButton(e.Graphics, _
        leftArrowRectangle, leftButtonState)
    ScrollBarRenderer.DrawArrowButton(e.Graphics, _
        rightArrowRectangle, rightButtonState)

    ' Draw a highlighted rectangle in the left side of the scroll 
    ' bar track if the user has clicked between the left arrow 
    ' and thumb.
    If leftBarClicked Then
        clickedBarRectangle.X = thumbLeftLimit
        clickedBarRectangle.Width = thumbRectangle.X - thumbLeftLimit
        ScrollBarRenderer.DrawLeftHorizontalTrack(e.Graphics, _
            clickedBarRectangle, ScrollBarState.Pressed)

    ' Draw a highlighted rectangle in the right side of the scroll 
    ' bar track if the user has clicked between the right arrow 
    ' and thumb.
    ElseIf rightBarClicked Then
        clickedBarRectangle.X = thumbRectangle.X + _
            thumbRectangle.Width
        clickedBarRectangle.Width = thumbRightLimitRight - _
            clickedBarRectangle.X
        ScrollBarRenderer.DrawRightHorizontalTrack(e.Graphics, _
            clickedBarRectangle, ScrollBarState.Pressed)
    End If
End Sub

Hinweise

Bevor Sie diese Methode verwenden, sollten Sie überprüfen, ob die IsSupported Eigenschaft zurückgegeben wird true.