private void DrawTrackBar(IntPtr hWnd)
{
ControlState state = ControlState.Normal;
bool horizontal = base.Orientation == Orientation.Horizontal;
ImageDc tempDc = new ImageDc(base.Width, base.Height);
RECT trackRect = new RECT();
RECT thumbRect = new RECT();
Graphics g = Graphics.FromHdc(tempDc.Hdc);
NativeMethods.SendMessage(
hWnd, TBM.TBM_GETCHANNELRECT, 0, ref trackRect);
NativeMethods.SendMessage(
hWnd, TBM.TBM_GETTHUMBRECT, 0, ref thumbRect);
Rectangle trackRectangle = horizontal ?
trackRect.Rect :
Rectangle.FromLTRB(
trackRect.Top, trackRect.Left,
trackRect.Bottom, trackRect.Right);
if (ThumbHovering(thumbRect))
{
if (Helper.LeftKeyPressed())
{
state = ControlState.Pressed;
}
else
{
state = ControlState.Hover;
}
}
using (PaintEventArgs pe = new PaintEventArgs(
g, ClientRectangle))
{
OnRenderBackground(pe);
}
int ticks = NativeMethods.SendMessage(
hWnd, TBM.TBM_GETNUMTICS, 0, 0);
if (ticks > 0)
{
List <float> tickPosList = new List <float>(ticks);
int thumbOffset = horizontal ?
thumbRect.Rect.Width : thumbRect.Rect.Height;
int trackWidth = trackRect.Right - trackRect.Left;
float tickSpace = (trackWidth - thumbOffset) / (float)(ticks - 1);
float offset = trackRect.Left + thumbOffset / 2f;
for (int pos = 0; pos < ticks; pos++)
{
tickPosList.Add(offset + tickSpace * pos);
}
using (PaintTickEventArgs pte = new PaintTickEventArgs(
g, trackRectangle, tickPosList))
{
OnRenderTick(pte);
}
}
using (PaintEventArgs pe = new PaintEventArgs(
g, trackRectangle))
{
OnRenderTrack(pe);
}
using (PaintThumbEventArgs pe = new PaintThumbEventArgs(
g, thumbRect.Rect, state))
{
OnRenderThumb(pe);
}
g.Dispose();
IntPtr hDC = NativeMethods.GetDC(hWnd);
NativeMethods.BitBlt(
hDC, 0, 0, base.Width, base.Height,
tempDc.Hdc, 0, 0, 0xCC0020);
NativeMethods.ReleaseDC(hWnd, hDC);
tempDc.Dispose();
}
protected virtual void OnRenderThumb(PaintThumbEventArgs e)
{
Graphics g = e.Graphics;
Rectangle rect = e.ClipRectangle;
ControlState state = e.ControlState;
ThumbArrowDirection direction = ThumbArrowDirection.None;
Color begin = ColorTable.ThumbBackNormal;
Color end = ColorTable.TrackInnerBorder;
Color border = ColorTable.ThumbBorderNormal;
float mode =
base.Orientation == Orientation.Horizontal ?
90f : 0f;
switch (base.Orientation)
{
case Orientation.Horizontal:
switch (base.TickStyle)
{
case TickStyle.None:
case TickStyle.BottomRight:
direction = ThumbArrowDirection.Down;
break;
case TickStyle.TopLeft:
direction = ThumbArrowDirection.Up;
break;
case TickStyle.Both:
direction = ThumbArrowDirection.None;
break;
}
break;
case Orientation.Vertical:
switch (base.TickStyle)
{
case TickStyle.TopLeft:
direction = ThumbArrowDirection.Left;
break;
case TickStyle.None:
case TickStyle.BottomRight:
direction = ThumbArrowDirection.Right;
break;
case TickStyle.Both:
direction = ThumbArrowDirection.None;
break;
}
break;
}
switch (state)
{
case ControlState.Hover:
begin = ColorTable.ThumbBackHover;
border = ColorTable.ThumbBorderHover;
break;
}
using (SmoothingModeGraphics sg = new SmoothingModeGraphics(g))
{
using (GraphicsPath path =
GraphicsPathHelper.CreateTrackBarThumbPath(
rect, direction))
{
using (LinearGradientBrush brush = new LinearGradientBrush(
rect, begin, end, mode))
{
Blend blend = new Blend();
blend.Positions = new float[] { 0, .2f, .5f, .8f, 1f };
blend.Factors = new float[] { 1f, .7f, 0, .7f, 1f };
brush.Blend = blend;
g.FillPath(brush, path);
}
using (Pen pen = new Pen(border))
{
g.DrawPath(pen, path);
}
}
rect.Inflate(-1, -1);
using (GraphicsPath path =
GraphicsPathHelper.CreateTrackBarThumbPath(
rect, direction))
{
using (Pen pen = new Pen(ColorTable.TrackInnerBorder))
{
g.DrawPath(pen, path);
}
}
}
}