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Drawstring on a panel change when other panel move over

I draw a rectangle panel with every button click. After that add a line on the edge of the rectangle and text on the center. But when I drag a panel move over other panel. The panel string will change. Please advice. I can't upload an image. How can I upload an image like that can show my problem more clearly.
This link http://i3.photobucket.com/albums/y53/ctkhai/1-4.png show the gui of my software. The upper left and lower left are picturebox. User add a "box" when click on button once and the "box" will show on upper left. User can drag the box to lower right and arrange all the box.
now the problem is when user drag the new added "box" and move over some other "box", the text i draw on previous box will change. like this http://i3.photobucket.com/albums/y53/ctkhai/2-4.png.
Update: I try to create a class for the tag. but it won't work, the number change again. It is the way I create class for the tag and read is wrong? code like below
Product _box = new Product();
List<Panel>product = new List<Panel>();
public class Product
{
public float X { set; get; } //box coordinate
public float Y { set; get; } //box coordinate
public int rotate { set; get; }
public int entryP { set; get; }
public int boxName { set; get; }
}
private void button_RecAdd_Click(object sender, EventArgs e)
{
locX = pictureBox_conveyor.Left + (pictureBox_conveyor.Width / 2 - box_y / 2);
locY = pictureBox_conveyor.Top + (pictureBox_conveyor.Height / 2 - box_x / 2);
_box.boxName = panelBoxNo;
_box.entryP = 1;
_box.rotate = 0;
_box.X = locX;
_box.Y = locY;
Panel box = new Panel();
box.Location = new Point(locX, locY);
box.Name = "box" + panelBoxNo;
box.Tag = _box;
box.Size = new Size(box_y, box_x);
box.BackColor = boxColor;
pbW = box.Width;
pbH = box.Height;
box.MouseDown += panelBox_MouseDown;
box.MouseMove += panelBox_MouseMove;
box.Paint += new PaintEventHandler((s, m) =>
{
Graphics g = m.Graphics;
g.TextRenderingHint = System.Drawing.Text.TextRenderingHint.ClearTypeGridFit;]
Product b = box.Tag as Product;
string text = b.boxName.ToString();
SizeF textSize = m.Graphics.MeasureString(text, Font);
PointF locationToDraw = new PointF();
locationToDraw.X = (pbW / 2) - (textSize.Width / 2);
locationToDraw.Y = (pbH / 2) - (textSize.Height / 2);
g.DrawString(text, Font, Brushes.Black, locationToDraw);
g.DrawRectangle(new Pen(Color.Black), 0, 0, pbW - 1, pbH - 1);
g.DrawLine(drawLine, 0, 0, 0, pbH);
});
product.Add(box);
panel_pelletLayout.Controls.Add(box);
box.BringToFront();
label_boxNo.Text = panelBoxNo.ToString();
panelBoxNo++;
}
private void panelBox_MouseDown(object sender, MouseEventArgs e)
{
Panel p = sender as Panel;
if (e.Button == MouseButtons.Left)
{
xPos = e.X;
yPos = e.Y;
if (p != null)
{
activePnlBox = p.Name;
textBox_selectedName.Text = p.Name;
textBox_selectedX.Text = p.Left.ToString();
textBox_selectedY.Text = p.Top.ToString();
}
}
}
private void panelBox_MouseMove(object sender, MouseEventArgs e)
{
Panel p = sender as Panel;
if (p != null)
{
if (e.Button == MouseButtons.Left)
{
p.Left = ((e.X + p.Left - (p.Width / 2)) / gripGap) * gripGap;
p.Top = ((e.Y + p.Top - (p.Height / 2)) / gripGap) * gripGap;
textBox_selectedX.Text = p.Left.ToString();
textBox_selectedY.Text = p.Top.ToString();
}
}
}

Your Paint event handler has to be responsible for drawing everything each time. Your code looks like it only draws one object.
When you drag something over your box, the box becomes invalid and needs to be painted from scratch which means it erases everything and calls your Paint handler. Your Paint event handler then just draws one object.
I suspect that what you want to do is keep a data structure of each item you draw and then have a loop in your Paint event handler that will draw all the objects you add.

Don't use variables that you defined outside a loop, in the paint event. That might be your problem.
Try to paint ((Panel)s).Name. Does this work properly?

Your title has got all of us confused.. You don't draw Rectangles, you create new Panels on each ButtonClick, right?
The code for the Paint event is not quite right, though. Just like in any Paint event you should use the built-in Graphics object. And as Hans has noted, you should not destroy/dispose things you didn't create.
The main problem you describe seems to be that your boxes have to paint themselves without referring to their real numbers. You should store their numbers e.g. in their Tags..
(Or you could extract it from their Names, like you do it in the MouseDown!)
box[panelBoxNo].Name = "box" + panelBoxNo;
box[panelBoxNo].Tag = panelBoxNo; // < === !!
//..
box[panelBoxNo].Paint += new PaintEventHandler((s, m) =>
{
Graphics g = m.Graphics; // < === !!
g.TextRenderingHint = System.Drawing.Text.TextRenderingHint.ClearTypeGridFit;
string text = box[panelBoxNo].Tag.ToString(); // < ===
SizeF textSize = g.MeasureString(text, Font);
PointF locationToDraw = new PointF();
locationToDraw.X = (pbW / 2) - (textSize.Width / 2);
locationToDraw.Y = (pbH / 2) - (textSize.Height / 2);
g.DrawString(text, Font, Brushes.Black, locationToDraw);
g.DrawRectangle(new Pen(Color.Black), 0, 0, pbW - 1, pbH - 1);
g.DrawLine(drawLine, 0, 0, 0, pbH);
// g.Dispose(); // < === !!
// m.Graphics.DrawImageUnscaled(drawBox, new Point(0, 0)); // < === !!
// m.Dispose(); // < === !!
});
And, as I have noted you should only use arrays if you (or the code) really knows the number of elements. In your case a List<Panel> will be flexible to hold any number of elements without changing any other part of the code, except the adding. You can access the List just like an Array. (Which it is behind the scenes..)
Update: The way I see it now, your problems all are about scope in one way or another.
Scope in its most direct meaning is the part of your code where a variable is known and accessible. In a slightly broader meaning it is also about the time when it has the value your need.
Your original problem was of the latter kind: You accessed the partNo in thr Paint event of the Panels, when it had long changed to a new, probably higher value.
Your current problem is to understand the scope of the variables in the ButtonClick event.
Usually this is no problem; looking at the pairs of braces, the scope is obvious. But: Here we have a dynamically created Lambda event and this is completely out of the scope of the Click event!! Behind the scenes this Paint event is removed from the Click code, placed in a new event and replaced by a line that simply adds a delegate to the Paint handler just like any regular event.
So: nothing you declare in the ButtonClick is known in the Paint code!
To access these data you must place them in the Panel properties, in our case in the Tag and access them via casting from the Sender parameter s!
So you need to change this line in the Paint event
Product b = box.Tag as Product;
to something like this:
Product b = ( (Panel) s ).Tag as Product;

Draw Border around ListBox

How would I go about drawing a border with a specified width and color around a listbox?
Can this be done without overriding the OnPaint method?

Following Neutone's suggestion, here is a handy function to add and remove a Panel-based border around any control, even if it is nested..
Simply pass in the Color and size you want, and if you want a BorderStyle. To remove it again pass in Color.Transparent!
void setBorder(Control ctl, Color col, int width, BorderStyle style)
{
if (col == Color.Transparent)
{
Panel pan = ctl.Parent as Panel;
if (pan == null) { throw new Exception("control not in border panel!");}
ctl.Location = new Point(pan.Left + width, pan.Top + width);
ctl.Parent = pan.Parent;
pan.Dispose();
}
else
{
Panel pan = new Panel();
pan.BorderStyle = style;
pan.Size = new Size(ctl.Width + width * 2, ctl.Height + width * 2);
pan.Location = new Point(ctl.Left - width, ctl.Top - width);
pan.BackColor = col;
pan.Parent = ctl.Parent;
ctl.Parent = pan;
ctl.Location = new Point(width, width);
}
}

You can place a list box within a panel and have the panel serve as a border. The panel backcolor can be used to create a colored border. This doesn't require much code. Having a colored border around a form component can be an effective way of conveying status.

The problem with the ListBox control is that it does not raise the OnPaint method so you can not use it to draw a border around the control.
There are two methods to paint a custom border around the ListBox:
Use SetStyle(ControlStyles.UserPaint, True) in the constructor, then you can use the OnPaint method to draw the border.
Override WndProc method that handles operating system messages identified in the Message structure.
I used the last method to paint a custom border around the control, this will eliminate the need to use a Panel to provide a custom border for the ListBox.
public partial class MyListBox : ListBox
{
public MyListBox()
{
// SetStyle(ControlStyles.UserPaint, True)
BorderStyle = BorderStyle.None;
}
protected override void WndProc(ref Message m)
{
base.WndProc(m);
var switchExpr = m.Msg;
switch (switchExpr)
{
case 0xF:
{
Graphics g = this.CreateGraphics;
g.SmoothingMode = Drawing2D.SmoothingMode.Default;
int borderWidth = 4;
Rectangle rect = ClientRectangle;
using (var p = new Pen(Color.Red, borderWidth) { Alignment = Drawing2D.PenAlignment.Center })
{
g.DrawRectangle(p, rect);
}
break;
}
default:
{
break;
}
}
}
}

Datagridview to draw wafer map

Currently I'm using C# datagridview to draw a wafer map which contains >500 rows and >700 columns.
However, there are a few issues:
Slow performance. As i need to adjust the column width, I have to loop through and assign individually.
for (int i = 0; i < this.dgvCompleteMapGrid.Columns.Count; i++)
{
this.dgvCompleteMapGrid.Columns[i].Width = 8;
}
I only need to draw the cell border for cells with value as a wafer map has an almost round shape. I'm using cellpainting event:
if (e.Value != null) {
if (e.Value.ToString() == "")
{
e.AdvancedBorderStyle.All = DataGridViewAdvancedCellBorderStyle.None;
}
else
{
if (e.Value.ToString() == "1")
{
e.CellStyle.BackColor = Color.Lime;
}
else
{
e.CellStyle.BackColor = Color.Red;
}
//check if the top border set None for neighbor empty value cell
if (e.AdvancedBorderStyle.Top.ToString() == "None")
{
e.AdvancedBorderStyle.Top = DataGridViewAdvancedCellBorderStyle.Single;
}
//repeat the same for left right and bottom
}
}
However, it seems like it will draw multiple border duplicate for most of the cells.
Is Datagridview recommended? I tried to draw rectangle on a panel and the performance is even worse.

Here's my Picturebox that allows for pixellated resizing (versus interpolated). E.g. similar to zooming in on a Microsoft Paint picture.
using System.Windows.Forms;
namespace WireWorld
{
public class ZoomablePicturebox : PictureBox
{
public ZoomablePicturebox()
{
}
protected override void OnPaint(PaintEventArgs pe)
{
pe.Graphics.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.None;
pe.Graphics.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.NearestNeighbor;
pe.Graphics.CompositingMode = System.Drawing.Drawing2D.CompositingMode.SourceCopy;
pe.Graphics.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighSpeed;
base.OnPaint(pe);
}
}
}
To generate the bitmap, I use something like this:
// Pick width and height for your case
Bitmap MyBitmap = new Bitmap(width, height);
using (var g = Graphics.FromImage(retVal))
g.Clear(BackColor); // Pick a background fill color
// Draw your points, whatever your loop needs to be and your point definition is
foreach (MyPointDef point in _Points)
{
MyBitmap.SetPixel(point.X, point.Y, point.Color);
}
Then I put a picture box in a panel on my form. The panel then provides the scrolling. I can set the picture and zoom as follows:
canvasPB.SizeMode = PictureBoxSizeMode.Zoom; // Ensures picture is resized as we resize picturebox
canvasPB.Image = MyBitmap;
canvasPB.Height = canvasPB.Image.Height * Zoom; // Zoom is 1, 2, 3, etc, for 1X, 2X, ...
canvasPB.Width = canvasPB.Image.Width * Zoom;
canvasPB being the name of the Picturebox on my form I'm trying to use as my canvas.

How to disable a User Control to draw it's background (or Region)

My question : How to disable a User Control to draw it's background (or Region)
Note : I already tried to override and empty OnPaintBackground or set background color to transparent.
I'm trying to bypass winform paint for my custom user controls in a custom container.
For that I thought to give a try to this : Beginners-Starting-a-2D-Game-with-GDIplus
My setup is :
A Form containing:
A User control (DrawingBoard)
A Container with elements I can drag and drop to this DrawingBoard (it's a listbox).
My render loop is inside the DrawingBoard with all elements specified in the previous link.
public DrawingBoard()
{
InitializeComponent();
//Resize event are ignored
SetStyle(ControlStyles.FixedHeight, true);
SetStyle(ControlStyles.FixedWidth, true);
SetStyle(System.Windows.Forms.ControlStyles.AllPaintingInWmPaint, true);// True is better
SetStyle(System.Windows.Forms.ControlStyles.OptimizedDoubleBuffer, true); // True is better
// Disable the on built PAINT event. We dont need it with a renderloop.
// The form will no longer refresh itself
// we will raise the paint event ourselves from our renderloop.
SetStyle(System.Windows.Forms.ControlStyles.UserPaint, false); // False is better
}
#region GDI+ RENDERING
public Timer t = new Timer();
//This is your BackBuffer, a Bitmap:
Bitmap B_BUFFER = null;
//This is the surface that allows you to draw on your backbuffer bitmap.
Graphics G_BUFFER = null;
//This is the surface you will use to draw your backbuffer to your display.
Graphics G_TARGET = null;
Size DisplaySize = new Size(1120, 630);
bool Antialiasing = false;
const int MS_REDRAW = 32;
public void GDIInit()
{
B_BUFFER = new Bitmap(DisplaySize.Width, DisplaySize.Height);
G_BUFFER = Graphics.FromImage(B_BUFFER); //drawing surface
G_TARGET = CreateGraphics();
// Configure the display (target) graphics for the fastest rendering.
G_TARGET.CompositingMode = CompositingMode.SourceCopy;
G_TARGET.CompositingQuality = CompositingQuality.AssumeLinear;
G_TARGET.SmoothingMode = SmoothingMode.None;
G_TARGET.InterpolationMode = InterpolationMode.NearestNeighbor;
G_TARGET.TextRenderingHint = TextRenderingHint.SystemDefault;
G_TARGET.PixelOffsetMode = PixelOffsetMode.HighSpeed;
// Configure the backbuffer's drawing surface for optimal rendering with optional
// antialiasing for Text and Polygon Shapes
//Antialiasing is a boolean that tells us weather to enable antialiasing.
//It is declared somewhere else
if (Antialiasing)
{
G_BUFFER.SmoothingMode = SmoothingMode.AntiAlias;
G_BUFFER.TextRenderingHint = TextRenderingHint.AntiAlias;
}
else
{
// No Text or Polygon smoothing is applied by default
G_BUFFER.CompositingMode = CompositingMode.SourceOver;
G_BUFFER.CompositingQuality = CompositingQuality.HighSpeed;
G_BUFFER.InterpolationMode = InterpolationMode.Low;
G_BUFFER.PixelOffsetMode = PixelOffsetMode.Half;
}
t.Tick += RenderingLoop;
t.Interval = MS_REDRAW;
t.Start();
}
void RenderingLoop(object sender, EventArgs e)
{
try
{
G_BUFFER.Clear(Color.DarkSlateGray);
UIPaint(G_BUFFER);
G_TARGET.DrawImageUnscaled(B_BUFFER, 0, 0);
}
catch (Exception ex)
{
Console.WriteLine(ex);
}
}
#endregion
Then my elements get the event fired and try to draw what I would like:
public override void UIPaint(Graphics g)
{
Pen p = new Pen(Color.Blue,4);
p.Alignment = System.Drawing.Drawing2D.PenAlignment.Inset;
g.DrawLines(p, new Point[] { new Point(Location.X, Location.Y), new Point(Location.X + Width, Location.Y), new Point(Location.X + Width, Location.Y + Height), new Point(Location.X, Location.Y + Height), new Point(Location.X, Location.Y - 2) });
g.DrawImageUnscaled(GDATA.GetWindowImage(), Location);
}
here is what happening on my DrawingBoard :
As I can't post image ... here is the link : http://s8.postimage.org/iqpxtaoht/Winform.jpg
The background is DarkSlateGray because my G_BUFFER state to clear each tick with that, Ok
The blue rectangle is what I paint, but it get cropped, KO
The Texture is cropped, KO
The region that crop my drawing is the control size.
So from there I've tried everything I could to disable WinForm to make some magic drawing in background. Tried to override and empty everything that got paint/update/refresh/invalidate/validate on Form/DrawingBoard/Elements but nothing allowed me to get my texture or drawing to not get cropped by the control background : (
I also tried to set the background of the Element as transparent and also to set Form.TransparencyKey = blabla with each element BackColor = blabla. But failed each time.
I'm certainly missing something : / But I don't know what.

Why don't you want to draw the background? To avoid problems with flickering in my custom control (derived from class Control), here's what I did:
(1) override OnPaintBackground:
protected override void OnPaintBackground(PaintEventArgs pevent)
{
}
(2) Draw in an offscreen Bitmap and then transfer it to the screen:
Bitmap _completeFrame;
protected override void OnPaint(PaintEventArgs pe)
{
DrawFrame(); // draws onto _completeFrame, calling new Bitmap()
// when _completeFrame is null or its Size is wrong
var g = pe.Graphics;
g.DrawImage(_completeFrame, new Point());
}

How come the graphics is not drawing onto the panel

I want to draw a grid in my panel. The graphics object (screen) that i created with bitmap isn't drawing in my panel. I tried with debugging to look if the screen wasn't drawing but that wasn't the case.
I tried creating the graphic object from the panel createGraphic method and the parameter painteventargs from the panel paint method. Both times when I used it to draw it with OnPaint it took too long.
public Main()
{
InitializeComponent();
backBuffer = new Bitmap(drawPanel.Width, drawPanel.Height);
screen = Graphics.FromImage(backBuffer);
sizeGridPoints = 2;
lenghtBetweenGridPoints = 10;
}
protected override void OnPaint(PaintEventArgs e)
{
base.OnPaint(e);
screen.Clear(Color.Black);
DrawGrid();
}
private void DrawGrid()
{
for(int x = lenghtBetweenGridPoints; x < drawPanel.Width; x += lenghtBetweenGridPoints)
{
for(int y = lenghtBetweenGridPoints; y < drawPanel.Height; y+= lenghtBetweenGridPoints)
{
screen.FillEllipse(new SolidBrush(Color.Green), x, y, sizeGridPoints, sizeGridPoints);
}
}
}

If you create a Graphics object from a bitmap, it will draw on this bitmap, not on your user interface. Instead, use the Graphics object from the PaintEventArgs e of your OnPaint method, to draw directly on the form or a control.
e.Graphics.FillEllipse(new SolidBrush(Color.Green), x, y, sizeGridPoints, sizeGridPoints);
You should never create your own Graphics object.
Create your own grid control:
public class GridPanel : Panel
{
public GridPanel()
{
DoubleBuffered = true; // Speeds up drawing, e.g. when panel is resized.
// Set default colors
BackColor = Color.Black;
ForeColor = Color.Green;
}
private int _lenghtBetweenGridPoints = 20;
public int LenghtBetweenGridPoints
{
get { return _lenghtBetweenGridPoints; }
set {
if (value != _lenghtBetweenGridPoints) {
_lenghtBetweenGridPoints = value;
Invalidate(); // Redraw the grid.
}
}
}
private int _sizeGridPoints = 3;
public int SizeGridPoints
{
get {
return _sizeGridPoints;
}
set {
if (value != _sizeGridPoints) {
_sizeGridPoints = value;
Invalidate(); // Redraw the grid.
}
}
}
protected override void OnPaint(PaintEventArgs e)
{
// e.Graphics.Clear(Color.Black); Not necessary. We use the BackColor of the panel.
if (LenghtBetweenGridPoints > 0 && SizeGridPoints > 0) {
e.Graphics.SmoothingMode = SmoothingMode.AntiAlias; // Optional.
using (var brush = new SolidBrush(ForeColor)) { // We use the ForeColor of the panel.
for (int x = LenghtBetweenGridPoints; x < Width; x += LenghtBetweenGridPoints) {
for (int y = LenghtBetweenGridPoints; y < Height; y += LenghtBetweenGridPoints) {
e.Graphics.FillEllipse(brush, x, y, SizeGridPoints, SizeGridPoints);
}
}
}
}
}
}
Once it has been compiled, it will automatically appear in toolbox window and you can drag and drop it on your form. You will even be able to edit the properties LenghtBetweenGridPoints and SizeGridPoints in the properties window.
You could also simply use the already available BackColor and ForeColor properties of the panel for the grid. This would allow you to set the colors in the properties window as well. Don't forget to dispose brushes that you have created.
Important: Do not call OnPaint directly. Instead, call the Invalidate or Refresh methods of the object you want to redraw. The point is that Windows decides when to call OnPaint. E.g. if Invalidate is called too frequently (e.g. 5 times in 1/60 seconds), Windows might decide to not call OnPaint every time, as this would create lag. On the other hand, when the user resizes the panel, Windows will call OnPaint automatically. If you restore a window that was minimized, this will re-paint the control as well. Otherwise it would remain black.