Progressbar has a maximumm is 10.
So I need to draw ten block without fill color before running progress.
Edit: added code
Public Class MyProgressBar
Inherits ProgressBar
Public Sub New()
Me.ForeColor = Color.Red
End Sub
Protected Overrides Sub OnPaint(e As PaintEventArgs)
MyBase.OnPaint(e)
For i as integer = 1 to 10
Dim g As Graphics = e.Graphics
Dim widthScale As Integer = Me.Width/10
g.DrawRectangle(Pens,Me.Left+(i*widthScale ),Me.Top, Me.Width / 10, Me.Height)
End For
End Sub
End Class
I try override OnPaint() but it's not working.
There are number of ways to do this. The simplest would be to create a transparent image of the boxes and put it on top of a regular progress bar.
Or you could create an array of text boxes, and play with their position, border and background until they look the way you want.
A more powerful way to do graphics is with the built-in .net graphics object. There's a brief introduction here
I am writing a simple test program that draws an axis/crosshair in a form. I have two text boxes, where I put in the x-center and y-center and draw the crosshair based on that. I want to be able to put in new coordinates, and move the crosshair to the new position, but when I do, the old drawing stays there. I want to erase the old drawing and then draw the new one.
My code is below:
Public Class Form1
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim mypen As Pen
mypen = New Pen(Drawing.Color.Red, 1)
Dim mygraphics As Graphics = Me.CreateGraphics
Dim x_center = Integer.Parse(xPos.Text)
Dim y_center = Integer.Parse(yPos.Text)
mygraphics.DrawLine(mypen, x_center - 50, x_center, x_center + 50, x_center)
mygraphics.DrawLine(mypen, y_center, y_center - 50, y_center, y_center + 50)
End Sub
End Class
The Drawing on a Control surface is usually handled through the Control's Paint() event, using its PaintEventArgs class object.
To raise the Paint() event of a Control, call its Invalidate() method.
(Note that the Invalidate() method has a number of overloads, some of which allows to re-paint only a defined region of the surface.)
If a Graphics object is created elsewhere (as you're doing now), the drawings performed with this object will persist or will be erased when you don't want to (e.g. if a Control needs to repaint itself - and this happens quite often - the drawings will be erased).
Also, the Graphics object can't be stored. It will become an invalid object as soon as a Control has repainted its surface.
You could re-design you code in this way.
Create a shared Pen (you can redefined it at any moment if you need to, using its properties) so you don't have to create a new one every time you need to draw something.
Use a shared Point field to store the current center of the drawing.
Move the Graphics.DrawLine() to the Paint event of your Form.
Remember to Dispose() the Pen object when the Form closes (you can use it's Dispose() pre-defined method).
Public Class Form1
Private mypen As Pen = New Pen(Color.Red, 1)
Private Position As Point = New Point(-1, -1)
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
If (Integer.TryParse(xPos.Text, Position.X) = True) AndAlso
(Integer.TryParse(yPos.Text, Position.Y) = True) Then
Me.Invalidate()
End If
End Sub
Private Sub Form1_Paint(sender As Object, e As PaintEventArgs) Handles MyBase.Paint
If Position.X > -1 Then
e.Graphics.DrawLine(mypen, Position.X - 50, Position.Y, Position.X + 50, Position.Y)
e.Graphics.DrawLine(mypen, Position.X, Position.Y - 50, Position.X, Position.Y + 50)
End If
End Sub
End Class
This is, however, not that much efficient, because you need to invalidate the entire Form.
For a full implementation, take a look a this Class (PasteBin - CrossHair).
Once I develop a vb6 code to use transparent controls (Dont remember if I use Buttons or PictrureBoxes) with coordinates as invisible tags & invisible labels to show the names of eachone at groupal photos like facebook does. Now Im trying to recreate the same code at vb.net but I can't reach to get it work..
If I use Buttons with transparent .backcolor, no-text and no-borders, flat style, etc. to mark the photo area, they become opaque when I move the mouse over the control. if I disable becomes invisible for the mouse-over function.
If I use empty PictureBoxes instead for the same purpouse, as are empty they became invisible at runtime also for the "mouse over" function...
I dont know wich empty or invisible control must use to this finality. any suggestion?
Here is an example of what I was talking about in my comments:
Public Class Form1
Private ReadOnly actionsByRectangle As New Dictionary(Of Rectangle, Action)
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
'If the user clicks near the top, left corner, display a message.
actionsByRectangle.Add(New Rectangle(10, 10, 100, 100),
Sub() MessageBox.Show("Hello World"))
'If the user clicks near the bottom, right corner, minimise the form.
actionsByRectangle.Add(New Rectangle(ClientSize.Width - 110,
ClientSize.Height - 110,
100,
100),
Sub() WindowState = FormWindowState.Minimized)
End Sub
Private Sub Form1_MouseClick(sender As Object, e As MouseEventArgs) Handles Me.MouseClick
For Each rectangle As Rectangle In actionsByRectangle.Keys
If rectangle.Contains(e.Location) Then
'We have found a rectangle containing the point that was clicked so execute the corresponding action.
actionsByRectangle(rectangle).Invoke()
'Don't look for any more matches.
Exit For
End If
Next
End Sub
'Uncomment the code below to see the click targets drawn on the form.
'Private Sub Form1_Paint(sender As Object, e As PaintEventArgs) Handles Me.Paint
' For Each rectangle As Rectangle In actionsByRectangle.Keys
' e.Graphics.DrawRectangle(Pens.Black, rectangle)
' Next
'End Sub
End Class
Note that I have added code there that can draw the boxes on the form if you want to see them, but those are just representations of the areas, not the Rectangle values themselves.
I'm trying to make a form resizable based on dragging a custom shape drawn at the corner of the panel. I have a code which works fantastic if it's drawn in the main form, but if I'm trying to draw it at the corner of a panel it doesn't work, I cannot resize the form. The code is optimized to be drawn in the form, could someone help me and update it to work in a panel too?
Protected Overrides Sub WndProc(ByRef m As Message)
MyBase.WndProc(m)
If m.Msg = &H84 Then
Dim pos = Me.PointToClient(New System.Drawing.Point(m.LParam.ToInt32() And &HFFFF, m.LParam.ToInt32() >> 16))
If pos.X >= Me.Width - grab AndAlso pos.Y >= Me.Height - grab Then
m.Result = New IntPtr(17)
End If
End If
End Sub
Private Const grab As Integer = 14
Protected Overrides Sub OnPaint(e As PaintEventArgs)
MyBase.OnPaint(e)
Dim rc = New System.Drawing.Rectangle(Me.Width - grab, Me.Height - grab, grab, grab)
ControlPaint.DrawSizeGrip(e.Graphics, System.Drawing.Color.FromArgb(250, 250, 250), rc)
End Sub
It looks like this:
Here
I managed to solve the problem by building my own custom control using GDI to paint the shape as standalone control, instead of painting it to an already built control, such panel.
As the title states, is it possible / how can you create a custom window to draw onto? Normally, you would just use a form and form controls, but I want my own window with a handle that I'll attach hooks to and handle the paint events and the like. Is this possible? Essentially, I just need a container for my program's image that isn't a Form. If not in VB.Net, is it possible in C#?
EDIT:
I'm just not very fond of how the window draws (even with control over paint event). I removed the form border and the control bar and replaced them with my own functions (to place the max/min/exit buttons, title, form borders + sizing, etc) so the form I'm using is essentially just a floating panel - though with built in hooks that are nice of course. But the form still flickers too much and so I wanted to handle everything myself. I use doublebuffering on all controls I use and I use setbounds to move/resize controls as opposed to setting width/height individually (reduced some of the flicker). I draw the form border in the form's paint event, the rest is drawn as controls (including the form's top bar).
I mostly hate the black boxes that I see when I expand the form (generally don't see that when decreasing window size, but still some small amount of flicker). An alternative method, perhaps a different draw style (in VB 2010) or something, would work as well I guess.
EDIT (again):
The black box issue happens regardless of how many controls are on the form. If I try to manually resize it (the custom empty form control posted below that inherits from Form), using setbounds on each mousemove during a click and drag event (does not occur when not intended, so I know it's not running the sub more than it has to).
EDIT (code):
http://img211.imageshack.us/img211/900/j9c.png
So even on a blank "SimpleForm" (as posted in the first answer") with no controls, when resized to be larger (in the pic, resized northeast), black boxes are drawn under where the form will be drawn. Controlstyles / backbuffering done as posted in the second answer, as well as the createparams posted by Hans. This is what I used to set the form bounds:
Protected Overrides ReadOnly Property CreateParams() As CreateParams
Get
Dim cp As CreateParams = MyBase.CreateParams
cp.ExStyle = cp.ExStyle Or &H2000000
cp.Style = cp.Style Or &H2000000
Return cp
End Get
End Property 'CreateParams
Public Sub New(ByRef ContentFolder As String, ByRef x As Integer, ByRef y As Integer, ByRef w As Integer, ByRef h As Integer)
FormBorderStyle = FormBorderStyle.None
'Note, I have tried the original suggested control styles in many combinations
Me.SetStyle(ControlStyles.OptimizedDoubleBuffer Or ControlStyles.ResizeRedraw Or ControlStyles.AllPaintingInWmPaint Or ControlStyles.UserPaint
UpdateStyles()
OL = x 'Used for resizing, to know what the original bounds were - especially in maximizing, didn't like the standards maximize call
OT = y
OW = w
OH = h
BackColor = Color.White
BorderColor = New Pen(BarColor.Color)
MinimumSize = New Size(200, 200)
TransparencyKey = Color.FromArgb(255, 255, 0, 128)
CF = ContentFolder
ControlBar = New FormBar(Me, "Explorer woo", CF)
AddHandler Me.Load, AddressOf EF_Load
AddHandler Me.MouseUp, AddressOf EF_MouseUp
AddHandler Me.MouseDown, AddressOf EF_MouseDown
AddHandler Me.MouseMove, AddressOf EF_MouseMove
AddHandler Me.LostFocus, AddressOf EF_LostFocus
End Sub
Public Sub EF_Load(ByVal sender As Object, ByVal e As EventArgs)
SetFormBounds(OL, OT, OW, OH)
End Sub
Protected Overrides Sub OnSizeChanged(ByVal e As EventArgs)
ControlBar.SetBar(Width) 'Sets the width of controlbar to new width, and updates position of the 3 top-right form buttons
If Not (_backBuffer Is Nothing) Then
_backBuffer.Dispose()
_backBuffer = Nothing
End If
RaiseEvent Resized(Me, e) 'Resizes controls in custom handler, in this example, it is unused - with controls, they don't flicker when resized though
MyBase.OnSizeChanged(e)
End Sub
Private Sub SetFormBounds(ByRef l As Integer, ByRef t As Integer, ByRef w As Integer, ByRef h As Integer)
If w < Me.MinimumSize.Width Then
w = Me.MinimumSize.Width
l = Left
End If
If h < Me.MinimumSize.Height Then
h = Me.MinimumSize.Height
t = Top
End If
If l = Left AndAlso t = Top AndAlso w = Width AndAlso h = Height Then Exit Sub
ControlBar.SetBar(w)
SetBounds(l, t, w, h)
'Used for detecting if user coords are on the form borders with L-shaped areas so as to not include too much of the interior of the bar, Borderthickness = pixel width of border
CornerRects = New List(Of Rectangle) From {{New Rectangle(0, 0, BorderThickness, 15)}, {New Rectangle(0, 0, 15, BorderThickness)}, {New Rectangle(Width - 15, 0, 15, BorderThickness)}, {New Rectangle(Width - BorderThickness, 0, BorderThickness, 15)}, {New Rectangle(0, Height - 15, BorderThickness, 15)}, {New Rectangle(BorderThickness, Height - BorderThickness, 10, BorderThickness)}, {New Rectangle(Width - BorderThickness, Height - 15, BorderThickness, 15)}, {New Rectangle(Width - 15, Height - BorderThickness, 10, BorderThickness)}}
End Sub
Protected Overrides Sub OnPaint(ByVal e As System.Windows.Forms.PaintEventArgs)
If _backBuffer Is Nothing Then
_backBuffer = New Bitmap(Me.ClientSize.Width, Me.ClientSize.Height)
End If
Dim g As Graphics = Graphics.FromImage(_backBuffer)
g.Clear(SystemColors.Control)
'Draw Control Box
g.TextRenderingHint = Drawing.Text.TextRenderingHint.SingleBitPerPixelGridFit
g.FillRectangle(BarColor, 0, 0, Width, ControlBar.Height)
If ControlBar.Title <> "" Then g.DrawString(ControlBar.Title, ControlBar.Font, ControlBar.FontBrush, ControlBar.TextLeft, ControlBar.TextTop)
g.DrawImage(FormBar.bmpCorners(0), 0, 0) 'Makes transparent corner, very small bitmap created at run-time
g.DrawImage(FormBar.bmpCorners(1), Width - FormBar.bmpCorners(0).Width, 0)
'Draw Control Box buttons top right
If ControlBar.ExitButton.Enabled = True Then g.DrawImage(ControlBar.ExitButton.Img, ControlBar.ExitButton.Rect.X, ControlBar.ExitButton.Rect.Y)
If ControlBar.MaximizeButton.Enabled = True Then g.DrawImage(ControlBar.MaximizeButton.Img, ControlBar.MaximizeButton.Rect.X, ControlBar.MaximizeButton.Rect.Y)
If ControlBar.MinimizeButton.Enabled = True Then g.DrawImage(ControlBar.MinimizeButton.Img, ControlBar.MinimizeButton.Rect.X, ControlBar.MinimizeButton.Rect.Y)
If Not ControlBar.Ico Is Nothing Then g.DrawImage(ControlBar.Ico, 5, 5) 'Draw Control Box icon (program icon) if it is set
'Draw the form border
For i = 0 To BorderThickness - 1
g.DrawLine(BorderColor, i, ControlBar.Height, i, Height - 1)
g.DrawLine(BorderColor, Width - 1 - i, ControlBar.Height, Width - 1 - i, Height - 1)
g.DrawLine(BorderColor, BorderThickness, Height - 1 - i, Width - BorderThickness, Height - 1 - i)
Next
g.Dispose()
e.Graphics.DrawImageUnscaled(_backBuffer, 0, 0)
End Sub
Protected Overrides Sub OnPaintBackground(ByVal pevent As PaintEventArgs)
End Sub
It is not really possible at all, in either language. This isn't a language thing, or even a framework (i.e. WinForms) thing. Rather, it's more because of the design of Windows itself. Essentially, everything in Windows is a window, and the Form class represents a basic top-level window that can be displayed directly on the desktop. If you want a window displayed on the desktop, you need to use the Form class. Moreover, if you want to have a window handle that you can attach hooks to, you'll need to use this class; it's the one with all the necessary plumbing to get that going.
But that doesn't mean it has to look like a default Form object does. The appearance is infinitely customizable. Start by setting the FormBorderStyle property of your form to remove the default window frame/chrome. That will give you a completely blank slate. Then, do like you said and handle its Paint event. Except that when you're wanting to handle the events of a derived class, you should override the OnXxx method directly, instead of subscribing to the events. So you'd have this code:
Public Class SimpleForm : Inherits Form
Public Sub New()
' Alter the form's basic appearance by removing the window frame,
' which gives you a blank slate to draw onto.
FormBorderStyle = FormBorderStyle.None
' Indicate that we're painting our own background.
SetStyle(ControlStyles.Opaque, True)
End Sub
Protected Overrides Sub OnPaint(e As System.Windows.Forms.PaintEventArgs)
' Call the base class.
MyBase.OnPaint(e)
' Paint the background...
e.Graphics.FillRectangle(Brushes.MediumAquamarine, Me.ClientRectangle)
' ...and then the foreground.
' For example, drawing an 'X' to mark the spot!
Using p As New Pen(Color.Navy, 4.0)
e.Graphics.DrawLine(p, 0, 0, Me.Width, Me.Height)
e.Graphics.DrawLine(p, Me.Width, 0, 0, Me.Height)
End Using
End Sub
End Class
Of course, such a window has severe usability problems. For starters, the user has no way to move it around on the screen or to close it. You'll need to handle those things yourself if you're eliminating the default border.
Can you show the method you are using to enable double buffering? Here's an article that addresses this. Perhaps it will help.
https://web.archive.org/web/20140811193726/http://bobpowell.net/doublebuffer.aspx
Basically, the code is like this (from the article):
Private _backBuffer As Bitmap
Public Sub New
InitializeComponents()
Me.SetStyle(ControlStyles.AllPaintingInWmPaint OR _
ControlStyles.UserPaint OR _
ControlStyles.DoubleBuffer, True)
End Sub
Protected Overrides Sub OnPaint(ByVal e As PaintEventArgs)
If _backBuffer Is Nothing Then
_backBuffer = New Bitmap(Me.ClientSize.Width, Me.ClientSize.Height)
End If
Dim g As Graphics = Graphics.FromImage(_backBuffer)
'Paint on the Graphics object here
g.Dispose()
'Copy the back buffer to the screen
e.Graphics.DrawImageUnscaled(_backBuffer, 0, 0)
End Sub 'OnPaint
'Don't allow the background to paint
Protected Overrides Sub OnPaintBackground(ByVal pevent As PaintEventArgs)
End Sub 'OnPaintBackground
Protected Overrides Sub OnSizeChanged(ByVal e As EventArgs)
If Not (_backBuffer Is Nothing) Then
_backBuffer.Dispose()
_backBuffer = Nothing
End If
MyBase.OnSizeChanged(e)
End Sub 'OnSizeChanged