TrackBarRenderer.GetTopPointingThumbSize(Graphics, TrackBarThumbState) Method

Definition

Namespace:

System.Windows.Forms

Assembly:

System.Windows.Forms.dll

Source:

TrackBarRenderer.cs

Returns the size, in pixels, of the track bar slider (also known as the thumb) that points up.

public:
 static System::Drawing::Size GetTopPointingThumbSize(System::Drawing::Graphics ^ g, System::Windows::Forms::VisualStyles::TrackBarThumbState state);

public static System.Drawing.Size GetTopPointingThumbSize (System.Drawing.Graphics g, System.Windows.Forms.VisualStyles.TrackBarThumbState state);

static member GetTopPointingThumbSize : System.Drawing.Graphics * System.Windows.Forms.VisualStyles.TrackBarThumbState -> System.Drawing.Size

Public Shared Function GetTopPointingThumbSize (g As Graphics, state As TrackBarThumbState) As Size

Parameters

g

Graphics

The Graphics this operation will use.

state

TrackBarThumbState

One of the TrackBarThumbState values that specifies the visual state of the slider.

Returns

Size

A Size that specifies the size, in pixels, of the slider.

Exceptions

InvalidOperationException

The operating system does not support visual styles.

-or-

Visual styles are disabled by the user in the operating system.

-or-

Visual styles are not applied to the client area of application windows.

Examples

The following code example uses the GetTopPointingThumbSize method to determine the size of the rectangle used by the DrawTopPointingThumb method to draw the slider. This code example is part of a larger example provided for the TrackBarRenderer class.

    // Calculate the sizes of the bar, thumb, and ticks rectangle.
private:
    void SetupTrackBar()
    {
        if (!TrackBarRenderer::IsSupported)
        {
            return;
        }

        Graphics^ g = this->CreateGraphics();

        // Calculate the size of the track bar.
        trackRectangle.X = ClientRectangle.X + 2;
        trackRectangle.Y = ClientRectangle.Y + 28;
        trackRectangle.Width = ClientRectangle.Width - 4;
        trackRectangle.Height = 4;

        // Calculate the size of the rectangle in which to
        // draw the ticks.
        ticksRectangle.X = trackRectangle.X + 4;
        ticksRectangle.Y = trackRectangle.Y - 8;
        ticksRectangle.Width = trackRectangle.Width - 8;
        ticksRectangle.Height = 4;

        tickSpace = ((float)ticksRectangle.Width - 1) /
            ((float)numberTicks - 1);

        // Calculate the size of the thumb.
        thumbRectangle.Size =
            TrackBarRenderer::GetTopPointingThumbSize(g,
            TrackBarThumbState::Normal);

        thumbRectangle.X = CurrentTickXCoordinate();
        thumbRectangle.Y = trackRectangle.Y - 8;
    }

// Calculate the sizes of the bar, thumb, and ticks rectangle.
private void SetupTrackBar()
{
    if (!TrackBarRenderer.IsSupported)
        return;

    using (Graphics g = this.CreateGraphics())
    {
        // Calculate the size of the track bar.
        trackRectangle.X = ClientRectangle.X + 2;
        trackRectangle.Y = ClientRectangle.Y + 28;
        trackRectangle.Width = ClientRectangle.Width - 4;
        trackRectangle.Height = 4;

        // Calculate the size of the rectangle in which to 
        // draw the ticks.
        ticksRectangle.X = trackRectangle.X + 4;
        ticksRectangle.Y = trackRectangle.Y - 8;
        ticksRectangle.Width = trackRectangle.Width - 8;
        ticksRectangle.Height = 4;

        tickSpace = ((float)ticksRectangle.Width - 1) /
            ((float)numberTicks - 1);

        // Calculate the size of the thumb.
        thumbRectangle.Size =
            TrackBarRenderer.GetTopPointingThumbSize(g,
            TrackBarThumbState.Normal);

        thumbRectangle.X = CurrentTickXCoordinate();
        thumbRectangle.Y = trackRectangle.Y - 8;
    }
}

' Calculate the sizes of the bar, thumb, and ticks rectangle.
Private Sub SetupTrackBar()
    If Not TrackBarRenderer.IsSupported Then
        Return
    End If
    Using g As Graphics = Me.CreateGraphics()
        ' Calculate the size of the track bar.
        trackRectangle.X = ClientRectangle.X + 2
        trackRectangle.Y = ClientRectangle.Y + 28
        trackRectangle.Width = ClientRectangle.Width - 4
        trackRectangle.Height = 4

        ' Calculate the size of the rectangle in which to 
        ' draw the ticks.
        ticksRectangle.X = trackRectangle.X + 4
        ticksRectangle.Y = trackRectangle.Y - 8
        ticksRectangle.Width = trackRectangle.Width - 8
        ticksRectangle.Height = 4

        tickSpace = (CSng(ticksRectangle.Width) - 1) / _
            (CSng(numberTicks) - 1)

        ' Calculate the size of the thumb.
        thumbRectangle.Size = _
            TrackBarRenderer.GetTopPointingThumbSize( _
            g, TrackBarThumbState.Normal)

        thumbRectangle.X = CurrentTickXCoordinate()
        thumbRectangle.Y = trackRectangle.Y - 8
    End Using
End Sub

Remarks

The size of the slider is determined by the current visual style of the operating system.

Before calling this method, you should verify that the value of the IsSupported property is true.