/// <summary>
/// Fires the DrawChannel events
/// </summary>
/// <param name="hdc">The device context for graphics operations</param>
protected virtual void OnDrawChannel(IntPtr hdc)
{
Graphics graphics = Graphics.FromHdc(hdc);
if (((this.OwnerDrawParts & TrackBarOwnerDrawParts.Channel) == TrackBarOwnerDrawParts.Channel) && !this.DesignMode)
{
TrackBarDrawItemEventArgs e = new TrackBarDrawItemEventArgs(graphics, this.ChannelBounds, (TrackBarItemState)this.ThumbState);
if (this.DrawChannel != null)
{
this.DrawChannel(this, e);
}
}
else
{
if (this.ChannelBounds.Equals(Rectangle.Empty))
{
return;
}
if (VisualStyleRenderer.IsSupported)
{
VisualStyleRenderer vsr = new VisualStyleRenderer("TRACKBAR", (int)NativeMethods.TrackBarParts.TKP_TRACK, (int)TrackBarItemState.Normal);
vsr.DrawBackground(graphics, this.ChannelBounds);
graphics.ResetClip();
graphics.Dispose();
return;
}
ControlPaint.DrawBorder3D(graphics, this.ChannelBounds, Border3DStyle.Sunken);
}
graphics.Dispose();
}
/// <summary>
/// Fires the tick drawing events
/// </summary>
/// <param name="hdc">The device context that holds the graphics operations</param>
protected virtual void OnDrawTicks(IntPtr hdc)
{
Graphics graphics = Graphics.FromHdc(hdc);
if (((this.OwnerDrawParts & TrackBarOwnerDrawParts.Ticks) == TrackBarOwnerDrawParts.Ticks) && !this.DesignMode)
{
TrackBarDrawItemEventArgs e = new TrackBarDrawItemEventArgs(graphics, this.ClientRectangle, (TrackBarItemState)this.ThumbState);
if (this.DrawTicks != null)
{
this.DrawTicks(this, e);
}
}
else
{
if (this.TickStyle == TickStyle.None)
{
return;
}
if (this.ThumbBounds.Equals(Rectangle.Empty))
{
return;
}
Color black = Color.Black;
if (VisualStyleRenderer.IsSupported)
{
VisualStyleRenderer vsr = new VisualStyleRenderer("TRACKBAR", (int)NativeMethods.TrackBarParts.TKP_TICS, ThumbState);
black = vsr.GetColor(ColorProperty.TextColor);
}
if (this.Orientation == Orientation.Horizontal)
{
this.DrawHorizontalTicks(graphics, black);
}
else
{
this.DrawVerticalTicks(graphics, black);
}
}
graphics.Dispose();
}
/// <summary>
/// Fires the DrawThumb events
/// </summary>
/// <param name="hdc">The device context for graphics operations</param>
protected virtual void OnDrawThumb(IntPtr hdc)
{
Graphics graphics = Graphics.FromHdc(hdc);
graphics.Clip = new Region(this.ThumbBounds);
if (((this.OwnerDrawParts & TrackBarOwnerDrawParts.Thumb) == TrackBarOwnerDrawParts.Thumb) && !this.DesignMode)
{
TrackBarDrawItemEventArgs e = new TrackBarDrawItemEventArgs(graphics, this.ThumbBounds, (TrackBarItemState)this.ThumbState);
if (this.DrawThumb != null)
{
this.DrawThumb(this, e);
}
}
else
{
// Determine the style of the thumb, based on the tickstyle
NativeMethods.TrackBarParts part = NativeMethods.TrackBarParts.TKP_THUMB;
if (this.ThumbBounds.Equals(Rectangle.Empty))
{
return;
}
switch (this.TickStyle)
{
case TickStyle.None:
case TickStyle.BottomRight:
part = (Orientation != Orientation.Horizontal) ? NativeMethods.TrackBarParts.TKP_THUMBRIGHT : NativeMethods.TrackBarParts.TKP_THUMBBOTTOM;
break;
case TickStyle.TopLeft:
part = (this.Orientation != Orientation.Horizontal) ? NativeMethods.TrackBarParts.TKP_THUMBLEFT : NativeMethods.TrackBarParts.TKP_THUMBTOP;
break;
case TickStyle.Both:
part = (this.Orientation != Orientation.Horizontal) ? NativeMethods.TrackBarParts.TKP_THUMBVERT : NativeMethods.TrackBarParts.TKP_THUMB;
break;
}
// Perform drawing
if (VisualStyleRenderer.IsSupported)
{
VisualStyleRenderer vsr = new VisualStyleRenderer("TRACKBAR", (int)part, ThumbState);
vsr.DrawBackground(graphics, this.ThumbBounds);
graphics.ResetClip();
graphics.Dispose();
return;
}
else
{
switch (part)
{
case NativeMethods.TrackBarParts.TKP_THUMBBOTTOM:
this.DrawPointerDown(graphics);
break;
case NativeMethods.TrackBarParts.TKP_THUMBTOP:
this.DrawPointerUp(graphics);
break;
case NativeMethods.TrackBarParts.TKP_THUMBLEFT:
this.DrawPointerLeft(graphics);
break;
case NativeMethods.TrackBarParts.TKP_THUMBRIGHT:
this.DrawPointerRight(graphics);
break;
default:
if ((this.ThumbState == 3) || !this.Enabled)
{
ControlPaint.DrawButton(graphics, this.ThumbBounds, ButtonState.All);
}
else
{
// Tick-style is both - draw the thumb as a solid rectangle
graphics.FillRectangle(SystemBrushes.Control, this.ThumbBounds);
}
ControlPaint.DrawBorder3D(graphics, this.ThumbBounds, Border3DStyle.Raised);
break;
}
}
}
graphics.ResetClip();
graphics.Dispose();
}