FillRectangle Parameter is not valid
This is the exception I am getting
System.ArgumentException was unhandled
HResult=-2147024809
Message=Parameter is not valid.
Source=System.Drawing
StackTrace:
at System.Drawing.Graphics.CheckErrorStatus(Int32 status)
at System.Drawing.Graphics.FillRectangle(Brush brush, Int32 x, Int32 y, Int32 width, Int32 height)
at System.Drawing.Graphics.FillRectangle(Brush brush, Rectangle rect)
at frmMain.drawCboxItem(Object sender, DrawItemEventArgs e) in frmMain.cs:line 465
at frmMain.cboxSectionCell_DrawItem(Object sender, DrawItemEventArgs e) in frmMain.cs:line 485
at System.Windows.Forms.ComboBox.OnDrawItem(DrawItemEventArgs e)
at System.Windows.Forms.ComboBox.WmReflectDrawItem(Message& m)
at System.Windows.Forms.ComboBox.WndProc(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
at System.Windows.Forms.UnsafeNativeMethods.SendMessage(HandleRef hWnd, Int32 msg, IntPtr wParam, IntPtr lParam)
at System.Windows.Forms.Control.SendMessage(Int32 msg, IntPtr wparam, IntPtr lparam)
at System.Windows.Forms.Control.ReflectMessageInternal(IntPtr hWnd, Message& m)
at System.Windows.Forms.Control.WmOwnerDraw(Message& m)
at System.Windows.Forms.Control.WmDrawItem(Message& m)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.ScrollableControl.WndProc(Message& m)
at System.Windows.Forms.ContainerControl.WndProc(Message& m)
at System.Windows.Forms.Form.WndProc(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
at System.Windows.Forms.UnsafeNativeMethods.CallWindowProc(IntPtr wndProc, IntPtr hWnd, Int32 msg, IntPtr wParam, IntPtr lParam)
at System.Windows.Forms.NativeWindow.DefWndProc(Message& m)
at System.Windows.Forms.Control.DefWndProc(Message& m)
at System.Windows.Forms.Control.WmOwnerDraw(Message& m)
at System.Windows.Forms.Control.WmDrawItem(Message& m)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.ComboBox.WndProc(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
InnerException:
And the code
if (e.Index > -1)
{
e.DrawBackground();
Brush bgColourBrush = null;
Brush fgColourBrush = null;
ComboBox combo = (ComboBox)sender;
objPDT.ListCell pdt = (objPDT.ListCell)combo.Items[e.Index];
if (e.ForeColor == SystemColors.HighlightText)
{
bgColourBrush = new SolidBrush(e.BackColor);
fgColourBrush = new SolidBrush(e.ForeColor);
}
else if (pdt.bgColour == null)
{
bgColourBrush = Brushes.Black;
fgColourBrush = Brushes.White;
}
else
{
bgColourBrush = pdt.bgColour;
fgColourBrush = pdt.fgColour;
}
// background
e.Graphics.FillRectangle(bgColourBrush, e.Bounds);
//foreground
e.Graphics.SmoothingMode = SmoothingMode.AntiAlias;
e.Graphics.DrawString(pdt.Name, combo.Font, fgColourBrush, e.Bounds.X, e.Bounds.Y);
}
And finally the values being passed to it:
pdt {
Section 8--> CELL} objPDT.ListCell
_bgcolour {Color = {Color [A=255, R=166, G=166, B=166]}} System.Drawing.Brush {System.Drawing.SolidBrush}
_CellID 27 int
_fgcolour {Color = {Color [A=255, R=255, G=255, B=255]}} System.Drawing.Brush {System.Drawing.SolidBrush}
_name "Section 8--> CELL" string
_SectionID 8 int
bgColour {Color = {Color [A=255, R=166, G=166, B=166]}} System.Drawing.Brush {System.Drawing.SolidBrush}
fgColour {Color = {Color [A=255, R=255, G=255, B=255]}} System.Drawing.Brush {System.Drawing.SolidBrush}
Name "Section 8--> CELL" string
Value "8:27" string
}
e.Bounds {X = 0 Y = 30 Width = 290 Height = 15} System.Drawing.Rectangle
Bottom 45 int
Height 15 int
IsEmpty false bool
Left 0 int
Location {X = 0 Y = 30} System.Drawing.Point
Right 290 int
Size {Width = 290 Height = 15} System.Drawing.Size
Top 30 int
Width 290 int
X 0 int
Y 30 int
Instead of creating Brush objects with each draw, perhaps you can make bgColourBrush and fgColourBrush global variables and then just change their color instead. Please forgive me if the code below doesn't compile as-is, I did this freehand. Like this:
if (e.Index > -1)
{
e.DrawBackground();
ComboBox combo = (ComboBox)sender;
objPDT.ListCell pdt = (objPDT.ListCell)combo.Items[e.Index];
if (e.ForeColor == SystemColors.HighlightText)
{
this.bgColourBrush.Color = e.BackColor;
this.fgColourBrush.Color = e.ForeColor;
}
else if (pdt.bgColour == null)
{
this.bgColourBrush.Color = Brushes.Black.Color;
this.fgColourBrush.Color = Brushes.White.Color;
}
else
{
this.bgColourBrush.Color = pdt.bgColour;
this.fgColourBrush.Color = pdt.fgColour;
}
// background
e.Graphics.FillRectangle(bgColourBrush, e.Bounds);
//foreground
e.Graphics.SmoothingMode = SmoothingMode.AntiAlias;
e.Graphics.DrawString(pdt.Name, combo.Font, fgColourBrush, e.Bounds.X, e.Bounds.Y);
}
UPDATE
So I see that your pdt ListCell object has a bgColour and a fgColour property. In order for my above solution to work, bgColour and fgColour need to be of type Color . Or if they are type SolidColorBrush, then you need to do this: bgColour.Color and fgColour.Color .
You should always dispose unmanaged classes like Brush , SolidBrush , Pen . Assuming the pdt.bgColour and pdt.fgColour are of type Color , something like the following code should prevent that crash. Warning: Untested code.
if (e.Index > -1)
{
e.DrawBackground();
SolidBrush bgColourBrush = null;
SolidBrush fgColourBrush = null;
ComboBox combo = (ComboBox)sender;
objPDT.ListCell pdt = (objPDT.ListCell)combo.Items[e.Index];
try {
if (e.ForeColor == SystemColors.HighlightText)
{
bgColourBrush = new SolidBrush(e.BackColor);
fgColourBrush = new SolidBrush(e.ForeColor);
}
else if (pdt.bgColour == null)
{
bgColourBrush = new SolidBrush(Color.Black);
fgColourBrush = new SolidBrush(Color.White);
}
else
{
bgColourBrush = pdt.bgColour;
fgColourBrush = pdt.fgColour;
}
// background
e.Graphics.FillRectangle(bgColourBrush, e.Bounds);
//foreground
e.Graphics.SmoothingMode = SmoothingMode.AntiAlias;
e.Graphics.DrawString(pdt.Name, combo.Font, fgColourBrush, e.Bounds.X, e.Bounds.Y);
} finally {
if(bgColorBrush != null) {
bgColorBrush.Dispose();
}
if(fgColorBrush != null) {
fgColorBrush.Dispose();
}
}
}
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