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Handling WndProc on a Panel

I am making a windows Winform with a custom resizer(no border). I draw a resizer grip and handle some messages in WndProc. Just a heads up: I don't know what happens inside the WndProc, I just know it does what I want it to do(I pasted as snippet from somehwere).
Now I want to add a panel that is docked to the bottom of my form. When I do this, however, my resizing functionality is gone. Is there some way to restore this functionality without having to program my own resizer in.
I would think the functionality is lost because it only handles the resizing on the main form and not on any of its controls.
protected override void WndProc(ref Message m)
{
if (m.Msg == 0x84)
{ // Trap WM_NCHITTEST
Point pos = new Point(m.LParam.ToInt32());
pos = this.PointToClient(pos);
if (
pos.X >= this.ClientSize.Width - cGrip &&
pos.Y >= this.ClientSize.Height - cGrip)
{
m.Result = (IntPtr)17; // HTBOTTOMRIGHT
return;
}
}
base.WndProc(ref m);
}
As I said in previous questions, I am not an experienced C# programmer at all. I have very little experience and the methods I use can probably be insanely optimized, so a detailed description of your answer would be very appreciated.

How to create transparent controls in Windows Forms when controls are layered

I am trying to implement a "Fillable Form" in which editable text fields appear over top of an image of a pre-preprinted form for a dot matrix printer. (using c# and Windows Forms and targeting .Net 2.0) My first idea was to use the image as the Windows Form background, but it looked horrible when scrolling and also did not scroll properly with the content.
My next attempt was to create a fixed-size window with a panel that overflows the bounds of the window (for scrolling purposes.) I added a PictureBox to the panel, and added my textboxes on top of it. This works fine, except that TextBoxes do not support transparency, so I tried several methods to make the TextBoxes transparent. One approach was to use an odd background color and a transparency key. Another, described in the following links, was to create a derived class that allows transparency:
Transparency for windows forms textbox
TextBox with a Transparent Background
Neither method works, because as I have come to find out, "transparency" in Windows Forms just means that the background of the window is painted onto the control background. Since the PictureBox is positioned between the Window background and the TextBox, it gives the appearance that the TextBox is not transparent, but simply has a background color equal to the background color of the Window. With the transparency key approach, the entire application becomes transparent so that you can see Visual Studio in the background, which is not what I want. So now I am trying to implement a class that derives from TextBox and overrides either OnPaint or OnPaintBackground to paint the appropriate part of the PictureBox image onto the control background to give the illusion of transparency as described in the following link:
How to create a transparent control which works when on top of other controls?
First of all, I can't get it working (I have tried various things, and either get a completely black control, or just a standard label background), and second of all, I get intermittent ArgumentExceptions from the DrawToBitmap method that have the cryptic message "Additional information: targetBounds." Based on the following link from MSDN, I believe that this is because the bitmap is too large - in either event it seems inefficient to capture the whole form image here because I really just want a tiny piece of it.
https://msdn.microsoft.com/en-us/library/system.windows.forms.control.drawtobitmap(v=vs.100).aspx
Here is my latest attempt. Can somebody please help me with the OnPaintBackground implementation or suggest a different approach? Thanks in advance!
public partial class TransparentTextbox : TextBox
{
public TransparentTextbox()
{
InitializeComponent();
SetStyle(ControlStyles.OptimizedDoubleBuffer |
ControlStyles.AllPaintingInWmPaint |
ControlStyles.ResizeRedraw |
ControlStyles.UserPaint, true);
}
protected override void OnPaintBackground(PaintEventArgs e)
{
//base.OnPaintBackground(e); // not sure whether I need this
if (Parent != null)
{
foreach (Control c in Parent.Controls)
{
if (c.GetType() == typeof(PictureBox))
{
PictureBox formImg = (PictureBox)c;
Bitmap bitmap = new Bitmap(formImg.Width, formImg.Height);
formImg.DrawToBitmap(bitmap, formImg.Bounds);
e.Graphics.DrawImage(bitmap, -Left, -Top);
break;
}
}
Debug.WriteLine(Name + " didn't find the PictureBox.");
}
}
}
NOTE: This has been tagged as a duplicate, but I referenced the "duplicate question" in my original post, and explained why it was not working. That solution only works if the TextBox sits directly over the Window - if another control (such as my Panel and PictureBox) sit between the window and the TextBox, then .Net draws the Window background onto the TextBox background, effectively making its background look gray, not transparent.

I think I have finally gotten to the bottom of this. I added a Bitmap variable to my class, and when I instantiate the textboxes, I am setting it to contain just the portion of the form image that sits behind the control. Then I overload OnPaintBackground to display the Bitmap, and I overload OnPaint to manually draw the text string. Here is the updated version of my TransparentTextbox class:
public partial class TransparentTextbox : TextBox
{
public Bitmap BgBitmap { get; set; }
public TransparentTextbox()
{
InitializeComponent();
SetStyle(ControlStyles.OptimizedDoubleBuffer |
ControlStyles.AllPaintingInWmPaint |
ControlStyles.ResizeRedraw |
ControlStyles.UserPaint, true);
}
protected override void OnPaint(PaintEventArgs e)
{
e.Graphics.DrawString(this.Text, this.Font, Brushes.Black, new PointF(0.0F, 0.0F));
}
protected override void OnPaintBackground(PaintEventArgs e)
{
e.Graphics.DrawImage(BgBitmap, 0, 0);
}
}
... and here is the relevant part of how I instantiate:
Bitmap bgImage = (Bitmap)Bitmap.FromStream(Document.FormImage);
PictureBox pb = new PictureBox();
pb.Image = bgImage;
pb.Size = pb.Image.Size;
pb.Top = 0;
pb.Left = 0;
panel1.Controls.Add(pb);
foreach (FormField field in Document.FormFields)
{
TransparentTextbox tb = new TransparentTextbox();
tb.Width = (int)Math.Ceiling(field.MaxLineWidth * 96.0);
tb.Height = 22;
tb.Font = new Font("Courier", 12);
tb.BorderStyle = BorderStyle.None;
tb.Text = "Super Neat!";
tb.TextChanged += tb_TextChanged;
tb.Left = (int)Math.Ceiling(field.XValue * 96.0);
tb.Top = (int)Math.Ceiling(field.YValue * 96.0);
tb.Visible = true;
Bitmap b = new Bitmap(tb.Width, tb.Height);
using (Graphics g = Graphics.FromImage(b))
{
g.DrawImage(bgImage, new Rectangle(0, 0, b.Width, b.Height), tb.Bounds, GraphicsUnit.Pixel);
tb.BgBitmap = b;
}
panel1.Controls.Add(tb);
}
I still need to work on how the text looks when I highlight it, and other things like that, but I feel like I am on the right track. +1 to Reza Aghaei and Mangist for commenting with other viable solutions!

Problems with Opacity

I'm trying to draw a semi-transparent background and then opaque elements on top of it.
How come I can't do something like this?
protected override void OnPaint(PaintEventArgs pe)
{
base.OnPaint(pe);
this.Opacity = 0.5;
pe.Graphics.FillRectangle(trans_black_brush, square_rect_big);
this.Opacity = 1;
pe.Graphics.FillRectangle(solid_red_brush, square_rect);
}
I'd appreciate if someone with better understanding of Form drawing could tell me why this doesn't work :)
Update:
The solution has 3 forms:
1) Main (program, buttons etc)
2) Semi-transparent background (screen size, using opacity)
3) Transparent background but solid brushes on top.
In Form2's constructor, I have this:
Foreground = new FormForeground(this);
and in Form3's constructor I have this:
private Form_FormBackground m_Parent;
public FormForeground(FormBackground parent)
{
InitializeComponent();
FormBackground m_Parent = parent;
...
}
Whenever the mouse is clicked and used to draw with in form 3,
I update the parent's rectangle like so:
private void _UpdateParent()
{
m_Parent.s_DrawArea = m_DrawArea;
m_Parent.Invalidate();
}
The parent, form 2 then does its OnPaint() where it draws the marked area.
It does work, however the drawing does lag a bit compared to drawing directly in form3 (which does not produce the desired results because the drawn area needs to be transparent across the forms).

This doesn't work because Opacity is a Property of the Form and will always make the whole form and all its content have the current Value. It is perfect for fading a form in or out, though..
You can't achieve what you want with only one form.
Instead you will need two sychronized forms.
One can be somewhat opaque and will let the desktop shine through; the other must be transparent by making use of the TransparencyKey property and you can draw onto it..
To synchronize the two forms code the Move and the ResizeEnd events.
For a first setup use code like this:
A dummy form to create the semi-transparent look:
Form form0 = new Form() { Opacity = 0.33f , BackColor = Color.Black};
In the Form1's Load event:
TransparencyKey = Color.FromArgb(255, 147, 151, 162);
BackColor = TransparencyKey;
DoubleBuffered = true;
form0.Enabled = false;
form0.BringToFront();
form0.Show();
form0.Size = Size;
form0.Location = Location;
BringToFront();
And in the Move and the ResizeEnd events maybe code like this:
private void Form1_Move(object sender, EventArgs e)
{
form0.Size = Size;
form0.Location = Location;
}
private void Form1_ResizeEnd(object sender, EventArgs e)
{
form0.Size = Size;
form0.Location = Location;
}
You also may want to study this post that also shows a way to sandwich two forms.
Note that I picked a rather random color instead of the more common named color Fuchsia or any named colors. This is because I
Don't want to accidentally use it in the drawing, thius breaking making wrong spots transparent, but also
Don't want to make the form transparent for mouse actions, aka 'click-through'. This happens when using Fuchsia (and possibly some other colors) for some weird legacy reasons..

How to custom-draw a margin in a TextBox?

I want to draw a margin line at 80 characters in a WinForms TextBox. Here is what I've tried, in my TextBox subclass:
protected override void WndProc(ref Message m)
{
base.WndProc(ref m);
const int WM_PAINT = 0x00F;
if (m.Msg == WM_PAINT) {
DrawMargin();
}
}
void DrawMargin()
{
using (Pen pen = new Pen(Color.Gray, 1)) {
using (Graphics graphics = CreateGraphics()) {
float charWidth = graphics.MeasureString("M", Font).Width;
graphics.DrawLine(pen, charWidth * 80, 0, charWidth * 80, Height);
}
}
}
There are at least three problems with this:
When the user enters some text, part of the line gets blanked out (goes white).
When the user selects some text with the mouse, the above happens again.
The line flickers when the TextBox is scrolled.
I notice that TED Notepad (which uses a Win32 EDIT control) is able to draw a margin without any problems, so it seems that it's possible to do what I want. Could anyone advise me how?

I am not sure about this method. But one thing you could look at trying is inserting an image into the text box. The image would of course be your margin, and the text would automatically start after the picture. To include a picture inside a text box see How can I insert an image into a RichTextBox?
Edit: I have also found this article http://www.codedblog.com/2007/09/17/owner-drawing-a-windowsforms-textbox/ which seems to facilitate painting in the background of a text box. The methods described here seems to take you a long way towards what you require.
Hope this helps.

As far as I can tell, the best way of doing this is simply to place a WinForms.Panel over the TextBox:
class FooTextBox : TextBox
{
public FooTextBox()
{
margin = new Panel();
margin.Enabled = false;
margin.BackColor = Color.LightGray;
margin.Top = 0;
margin.Height = ClientSize.Height;
margin.Left = <whatever>;
margin.Width = 1;
Controls.Add(margin);
}
Panel margin;
}
Since the panel is not Enabled, it doesn't take mouse input.

How to fake mouse cursor position in Windows Forms C#?

I have this Windows Forms application with a simple balloon tooltip. Depending on the application's window location on the desktop and the mouse cursor location, the balloon 'tip' (or balloon pointing arrow) may or may not be pointing to the location I want.
For instance, my app snaps to the desktop sides and when it's snapped to the right side, if the mouse cursor is below 100px of the right side, the balloon 'tip' will point to the wrong place. But if the mouse cursor is anywhere else, it will point to the right place.
In this situation I wanted to fake the mouse cursor position (without actually changing the mouse cursor position) to be somewhere else so the the problem wouldn't occur.
Is this possible? How can I achieve this?
private void noteTitleInput_KeyPress(object sender, KeyPressEventArgs e) {
if(e.KeyChar == Convert.ToChar(Keys.Return, CultureInfo.InvariantCulture) && noteTitleInput.Text.Length > 0) {
e.Handled = true;
noteInputButton_Click(null, null);
} else if(!Char.IsControl(e.KeyChar)) {
if(Array.IndexOf(Path.GetInvalidFileNameChars(), e.KeyChar) > -1) {
e.Handled = true;
System.Media.SystemSounds.Beep.Play();
noteTitleToolTip.Show("The following characters are not valid:\n\\ / : * ? < > |",
groupNoteInput, 25, -75, 2500);
return;
}
}
noteTitleToolTip.Hide(groupNoteInput);
}

I'm not quite sure why do you need to set cursor position, because you can set tool tip to appear where you tell it, and not necessarily where the mouse is.
For example:
tooltip1.Show("My tip", controlOnWhichToShow, 15, 15);
would display the tip at upper left corner of the controlOnWhichToShow, 15 points away from edges.
If I misunderstood you, than please specify at which point in time is the mouse position being used.

If you sync the MouseHover event, you can create the Tooltip as veljkoz describes. In this way you can place the tooltip as you like. The code would look smething like this:
protected override void OnMouseHover(EventArgs e)
{
ToolTip myToolTip = new ToolTip();
myToolTip.IsBalloon = true;
// TODO The x and y coordinates should be what ever you wish.
myToolTip.Show("Helpful Text Also", this, 50, 50);
base.OnMouseHover(e);
}
Hope that helps.

In Windows Forms the mouse is captured by the control when the user presses a mouse button on a control, and the mouse is released by the control when the user releases the mouse button.
The Capture property of the Control class specifies whether a control has captured the mouse. To determine when a control loses mouse capture, handle the MouseCaptureChanged event.
Only the foreground window can capture the mouse. When a background window attempts to capture the mouse, the window receives messages only for mouse events that occur when the mouse pointer is within the visible portion of the window. Also, even if the foreground window has captured the mouse, the user can still click another window, bringing it to the foreground. When the mouse is captured, shortcut keys do not work.
More here. Mouse Capture in Windows Forms

You can do what you say with a Class. You can do it in a very simple way.
one create class and
namespace MousLokasyonbulma
{
class benimtooltip : ToolTip
{
[System.Runtime.InteropServices.DllImport("User32.dll")]
static extern bool MoveWindow(IntPtr h, int x, int y, int width, int height, bool redraw);
public benimtooltip()
{
this.OwnerDraw = true;
this.Draw += Benimtooltip_Draw;
}
private void Benimtooltip_Draw(object sender, DrawToolTipEventArgs e)
{
e.DrawBackground();
e.DrawBorder();
e.DrawText();
var t = (ToolTip)sender;
var h = t.GetType().GetProperty("Handle",
System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance);
var handle = (IntPtr)h.GetValue(t);
var location = new Point(650, 650);
var ss= MoveWindow(handle, location.X, location.Y, e.Bounds.Width, e.Bounds.Height, false);
}
}
}
full Code MyGithup
Example Project image
https://i.hizliresim.com/1pndZG.png
https://i.hizliresim.com/Lvo3Rb.png