I am overriding the paint event as I need to give a text box an extra property. In this case the extra property is a border colour for a text box. When the User Control which contains the text boxes appears it does not fire the OnPaint event. I've no idea why this is happening.
My code is as follows
CustomTaskBox class
Public Class CustomTextBox
Inherits TextBox
<Browsable(True)>
<Category("Extended Properties")>
<Description("Set TextBox border Color")>
Public Sub New()
Multiline = False
BorderStyle = BorderStyle.None
End Sub
Protected Overrides Sub OnPaint(e As PaintEventArgs)
MyBase.OnPaint(e)
Dim buttonPen = New Pen(Color.Firebrick, 3)
Dim buttonRect = New Rectangle(0, 0, Size.Width - 1, Size.Height - 1)
e.Graphics.DrawRectangle(buttonPen, buttonRect)
End Sub
End Class
Main Class
Dim _NewTextBox As New CustomTextBox
_NewTextBox.Name = textBoxName
_NewTextBox.Multiline = multiline
_NewTextBox.Text = textBoxText
_NewTextBox.Top = topForNextControl
_NewTextBox.Left = 17
_NewTextBox.Width = textBoxWidth * widthScaleFactor
_MainContent.Controls.Add(_NewTextBox)
If I recall correctly - you need to useInvalidate(); to notify that control needs to be repainted.
Greetings,
I want To create a graphic representation of a seating chart (could be in a wedding venue or in cars...). I used a splitted panel, in the splittedPanel1 i put the buttons to create the cars, and inside the splitted panel2 i want to put the graphic representation. Inside SplittedPanel2, I've created a panel and a pictureBox (to represent some fixed areas in the real world).
I've also created a class called SimpleCar. SimpleCar is composed of 5 TextBox (es) and a PictureBox all in a panel to represent a car: the textBoses represent the passengers names and the car label, and the pictureBox to put an image representing a car (or a table). I've also made a sub to Add dynamically a SimpleCar.
2 problems occur when i want to move this new panel (dynamically created), using MouseDown and MouseUp events:
- first pb: while moving the existing panel, the screen flashes and the movement is not smooth
- second pb: i can't move a panel dynamically created
Note that moving a PictureBox by this code is very smooth but moving a panel is not user friendly.
I expect moving a dynamically created a panel smoothly, or should I reconsider displaying the cars in another way than in a panel?
Knowing that the final purpose of the code is to export a picture of all the created tables in the venue. I also tested the code with a groupBox and the results aren't good.
The simpleCar class is described in the code below:
Class SimpleCar
Public carNameBox, passengerNameBox1, passengerNameBox2,
passengerNameBox3, passengerNameBox4 As TextBox
Public carPictureBox As PictureBox
Public carGroup As Panel
Public Sub New()
carGroup = New Panel
carNameBox = New TextBox With {.Text = "carNmBx",
.BackColor = Color.Yellow,
.Name = "carNmBx"}
passengerNameBox1 = New TextBox With {.Text = "txtPassNmBx1",
.BackColor = Color.BlanchedAlmond,
.Name = "TextBox1"}
passengerNameBox2 = New TextBox With {.Text = "txtPassNmBx2",
.BackColor = Color.AliceBlue,
.Name = "TextBox2"}
passengerNameBox3 = New TextBox With {.Text = "txtPassNmBx3",
.BackColor = Color.Azure,
.Name = "TextBox3"}
passengerNameBox4 = New TextBox With {.Text = "txtPassNmBx4",
.BackColor = Color.Cyan,
.Name = "TextBox4"}
carPictureBox = New PictureBox With {.Text = "picBx1",
.BackColor = Color.BlanchedAlmond,
.Name = "picBox1"}
Dim fdialog As New OpenFileDialog()
fdialog.FileName = String.Empty
fdialog.Multiselect = True
If fdialog.ShowDialog = DialogResult.OK Then
If fdialog.FileNames.Length = 2 Then
carPictureBox.Image = Image.FromFile(fdialog.FileNames(0))
ElseIf fdialog.FileNames.Length = 1 Then
carPictureBox.Image = Image.FromFile(fdialog.FileName)
End If
End If
carGroup.Controls.Add(carPictureBox)
carGroup.Controls.Add(carNameBox)
carGroup.Controls.Add(passengerNameBox1)
carGroup.Controls.Add(passengerNameBox2)
carGroup.Controls.Add(passengerNameBox3)
carGroup.Controls.Add(passengerNameBox4)
End Sub
End Class
To Add dynamically a SimpleCar in the code below:
Public Sub Add_car()
Dim carType As SimpleCar
carType = New SimpleCar
Dim carPs1 = carType.passengerNameBox1
Dim carPs2 = carType.passengerNameBox2
Dim carPs3 = carType.passengerNameBox3
Dim carPs4 = carType.passengerNameBox4
Dim carNm = carType.carNameBox
Dim carPic = carType.carPictureBox
Dim carGroupBox = carType.carGroup
SplitContainer1.Panel2.Controls.Add(carGroupBox)
End Sub
So the problem occurs when i use this code to move a panel (if you replace PictureBox by Panel, even GroupBox) (it worked fine when I wanted to move one control: PictureBox1 in this sample):
'Drag To move PictureBox1 along with mouse-------------------------------------------
Dim oldX As Short
Dim oldY As Short
Private Sub PictureBox1_MouseDown(ByVal sender As Object, ByVal e As MouseEventArgs) Handles PictureBox1.MouseDown
Dim X As Single = e.X
Dim Y As Single = e.Y
PictureBox1.Cursor = Cursors.SizeAll
oldX = CShort(X)
oldY = CShort(Y)
End Sub
Private Sub PictureBox1_MouseUp(ByVal sender As Object, ByVal e As MouseEventArgs) Handles PictureBox1.MouseUp
Dim X As Single = e.X
Dim Y As Single = e.Y
PictureBox1.Cursor = Cursors.Default
End Sub
' to limit the movement within the app----------------------------------
Private Sub PictureBox1_MouseMove(ByVal sender As Object, ByVal e As MouseEventArgs) Handles PictureBox1.MouseMove
If e.Button = MouseButtons.Left Then
Dim ProposedLocation As New Point(PictureBox1.Left - (oldX - e.X), PictureBox1.Top - (oldY - e.Y))
PictureBox1.Left = CInt(IIf(ProposedLocation.X < 0, 0, IIf(ProposedLocation.X > SplitContainer1.Panel2.Width - PictureBox1.Width, SplitContainer1.Panel2.Width - PictureBox1.Width, ProposedLocation.X)))
PictureBox1.Top = CInt(IIf(ProposedLocation.Y < 0, 0, IIf(ProposedLocation.Y > SplitContainer1.Panel2.Height - PictureBox1.Height, SplitContainer1.Panel2.Height - PictureBox1.Height, ProposedLocation.Y)))
End If
End Sub
In VB.Net, how can I call thePublic Sub using a button click?
Here's what I have so far:
Public Sub SetThreshold(ByVal e As PaintEventArgs)
' Open an Image file, and draw it to the screen.
Dim Image As New Bitmap(PictureBox1.Image)
PictureBox1.Image = Image
e.Graphics.DrawImage(Image, 20, 20)
' Create an ImageAttributes object, and set its color threshold.
Dim imageAttr As New ImageAttributes
imageAttr.SetThreshold(0.7F)
' Draw the image with the colors bifurcated.
Dim rect As New Rectangle(300, 20, 200, 200)
e.Graphics.DrawImage(Image, rect, 0, 0, 200, 200, GraphicsUnit.Pixel, imageAttr)
End Sub
Imagine a list where the items had child controls (say, a list of songs with media controls).
I'd like for the child to show on MouseMove of the parent.
The problem I'm facing is that the MouseLeave event, which hides the child controls, fires when the mouse leaves the parent to go into the children (which is completely understandable).
How would one overcome this?
I don't have this problem with the text as I have painted it with graphics. I don't want to paint the children as they will need individual event handlers.
All of the items are added dynamically at runtime.
EDIT
It appears I am, in fact, getting the issue with the MouseLeave event of the graphics.
At the moment, I have the parent's MouseMove event set the ForeColor to blue and the MouseLeave event setting the colour to white. The textis drawn on paint (I use the ForeColor of the parent when I paint the string). It seems that if I leave the parent via the graphics (the top of the graphics is at 0), the ForeColor remains blue.
The code
Private Sub ListItem_MouseLeave(sender As Object, e As EventArgs) Handles Me.MouseLeave
Me.ForeColor = Me.Parent.ForeColor
_controls.Hide()
End Sub
Private Sub ListItem_MouseEnter(sender As Object, e As EventArgs) Handles Me.MouseEnter
Me.ForeColor = SystemColors.HotTrack
If _controls Is Nothing Then
Dim p As New Panel
With p
.BackColor = Color.FromArgb(23, 23, 23)
.Width = Me.Height * 1
.Height = Me.Height
.Left = Me.Width - Me.Height
.Top = 0
.ForeColor = Me.Parent.ForeColor
.Anchor = AnchorStyles.Right
End With
Me.Controls.Add(p)
_controls = p
Else
_controls.Show()
End If
End Sub
Private Sub ListItem_Paint(sender As Object, e As PaintEventArgs) Handles Me.Paint
Dim strLen As SizeF = e.Graphics.MeasureString(SongName, Me.Font)
e.Graphics.DrawString(getTrimmedString(SongName, SongNameMaxWidth), Me.Font, New SolidBrush(Me.ForeColor), New Point(3, (Me.Height / 2) - (strLen.Height / 2)))
End Sub
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