I'm having an issue when passing an object of type Dictionary(Of Int16, Polygon) as an argument to a backgroundworker so the background worker is able to access the Polygons in the Dictionary. I'm getting the typical "The calling thread cannot access this object because a different thread owns it" message.[code]...
View 2 Replieshow do you draw or place a polygon/line within another polygon e.g. a circle within a triangle.
View 5 Replieshow can i get the points which make a polygon from a region which was derived from the polygon's points?
View 1 RepliesIn one application, I need use 4 simultaneous threads.When the threads finished, I need to update the text of a TextBox.So, I create 4 Textbox, and I wanna the threads change the text to FINISHED.Each thread change one distinct TB.I use this "example"
Dim Terminados As Integer = 0
Private Sub frmEnviarMensagem_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Timer1.Enabled = True
Timer1.Start()
[code]....
The problem is, I have an error in the red lines.The error is: INVALIDOPERATIONEXCEPTION "Cross-Thread operation not valid: Control tbPlaca1 Accessed from a thread other than the thread it was created on."I don't use cross threading. Each TB only was accessed for the correspondent thread, and for the "main program".
This is the error message I am getting:
"Cross-thread operation not valid: Control 'Panel1' accessed from a thread other than the thread it was created on." The reason I am getting this error is because I am opening up a new form and then calling these three things:
Panel1.Show()
Label1.Show()
Label2.Show()
why I get this error message because it doesn't occur normally if I open Form2 after closing Form1, it only occurs when I open Form2 after closing Form4.
I have done a program using vb2005 to display reading from my microcontroller bs2 board but have encountered some problems. My code are as follows.
Dim Stop_Rx As Boolean
Private Sub btnRead_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnRead.Click
SerialPort1.Open()
[code]....
I've encounter an error which is, (Cross-thread operation not valid: Control 'txt1' accessed from a thread other than the thread it was created on.)
When my client try to connect to server I'm getting this error : Cross-thread operation not valid: Control 'l_users' accessed from a thread other than the thread it was created on.
Private Sub _socketManager_onConnectionAccept(ByVal SocketID As String) Handles _socketManager.onConnectionAccept
l_Users.Items.Add(SocketID)
End Sub
Would anyone be able to help me here please. I'm fairly new to VB.net and threading so im just trying to figure out what is happening.When I debug this I am getting the error thread operation not valid: Control 'ProgressBar1' accessed from a thread other than the thread it was created on.
I'm a little lost as to why the error is occuring or how to fix it. I've had to put the progress bar in a separate thread otherwise the GUI crashes
[Code]...
My understanding is that thread.join will suspend the execution of code on the calling thread until the spawned thread finishes or is aborted...
With that in mind, I tried this:
For i = 1 to 50
threads = New Thread(AddressOf test)
threads.IsBackground = True
threads.SetApartmentState(ApartmentState.STA)
[CODE]...
However, the rest of the code runs when the loop finishes, not waiting for all the spawned threads to finish. Since the rest of the code needs the threads to finish (otherwise the rest will error).
I have written an application that loads a form - frmCad as well as AutoCad. It does this via a class which detects when AutoCad quits.
Friend Class CadApp Private WithEvents AppObject As AcadApplication... Private Sub AppObject_BeginQuit(ByRef Cancel As Boolean) Handles AppObject.BeginQuit RaiseEvent Quit() End SubEnd Class
My main class loads frmCad as well as CadApp.
Public Class Cad Private WithEvents frmCad As CadForm Private WithEvents app As CadApp... Public Sub ShowForm() If frmCad Is Nothing Then frmCad = New CadForm frmCad.Visible = True End Sub... Private Sub app_Quit() Handles app.Quit frmCad.Dispose() frmCad = Nothing .... End Sub
When I debug the program, it stops at frmCad.Dispose()The program continues to execute, but all the code after it fails to work.Looking more carefully I get an error message which contains:-Cross-thread operation not valid: Control 'Autocad' accessed from a thread other than the thread it was created on.
My error:Cross-thread operation not valid: Control 'label2' accessed from a thread other than the thread it was created on. I want to be able to give my Public RunBot() sub access to edit Labels, buttons, etc without an error.
[Code]...
I'm getting the 'System.InvalidOperationException' error on acccessing a thread from other than where it was created. My code is:
'Required by the Windows Form Designer
Public components As System.ComponentModel.IContainer ' changed from private
[code]....
My problem is Cross-thread operation not valid: Control 'statusHO' accessed from a thread other than the thread it was created on.
System.InvalidOperationException was unhandled
Message="Cross-thread operation not valid: Control 'statusHO' accessed from a thread other than the thread it was created on."
Source="System.Windows.Forms"
StackTrace:
[Code]...
i used it and it works fine then. but as it is mentioned its not a good practice to use it. So what should i do? is it ok if i use this as i am not able to use correct practice. Mine application is not for enterprise purpose. its just my class project, and it works fine even if i put application working in background. System works ok. I dont know how to correct this error.As i dont have that much knowlege of threads.
So please guide me how to fix this in correct way otherwise i am force to go for bad programming practice
Please refer to Windows Mobile Developer Center > Smart Device Development Forums > Windows Mobile Development > Appendtext not working for all my code details
Cross-thread operation not valid: Control 'lv1' accessed from a thread other than the thread it was created on.
Dim lvi As ListViewItem
For Each lvi In lv1.Items
[code]....
how can i calculate the 13 points on the polygon (see image)?
the 2 points either side of the centre points
are +/- width or height * 0.2761423749154
i have 4 known points, topLeft, topRight, bottomRight, + bottomLeft.
the polygon won't always be a regular rectangle as it is in the image
If I have some polygon lat lon coordinates stored in sqlserver db. how would I query it to see if a point was in contained within a polygon?
View 2 RepliesI just finished creating a program where you find the area of a 5 sided polygon. But not I want to actually draw the polygon given the coordinates
Private Sub PI_Estimation_Paint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles Me.Paint
Dim myGraphics As Graphics
[code].....
I have a collection of latitudes and longitudes and I'll be grabbing sets of these and want to draw a polygon based on them.The datasets won't be the outline so will need an algorithm to establish which ones make up the outline of a polygon containing all the latitudes and longitudes supplied. This polygon needs to be flexible so the polygon can be concave if the points dictate that.
My code below produces a horrible looking polygon. As explain in my first post I want to create a nice concave or convex polygon based on the latlng's provided.Just need a way of plotting the outer latlngs.
function initialize() {
var myLatLng = new google.maps.LatLng(51.407431, -0.727142);
var myOptions = {
[code]....
I'm making a game for a school project We've created a character that moves around the screen and creates blocks behind him as he moves around.We want to make it so that when the character moves from one edge of the screen to another, it fills the screen. So in order to do this we have a Points array that stores every point the character touches on his way to a wall.We then fill the Points array with "formsurface.fillPolygon(Points)"Now I'm wondering is there anyway we can retrieve all the points that are WITHIN or INSIDE the Points array we made? ( remember the points array simply contains the outline or the path the character created, we're filling inside that outline)
View 1 Repliesi dont know how to do this.i need to create a macro to use on microsoft excel to calculate the area of any polygon. my problem is similar to this one: [URL]..but de vb code is not working for me.in attach i send the excel page.i also have to calculate the coordenates of the "center of mass", Cx and Cy using diferents functions.
View 1 Replieshow can i inflate an array of points which describe a polygon?
View 1 RepliesOn click, I'd like this piece of code to create new polygon, shown in multiples with different coordinates and colors, sizes and orientation. Color and polygon in multiples works. My issue is I'd like to add more code that will allow each of the multiple polygon created scaled randomly and rotated. How to keep the polygons inside the canvas?
So far looks like this when user clicks start: [URL]
Code:
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.Windows.RoutedEventArgs) Handles startButton.Click
Dim endCount As Integer = random.Next(1, 10)
Dim plotPoint As New Point
For count = 1 To endCount
[Code] .....
I'm working on a small freeware application in Visual Studio 2008 Standard that will match geographic data to a geographic position. For this I need some mathemathical functions and one of them is how to detect if a point is inside a polygon. There's a great solution for this from the Microsoft team at: [URL]
but it is in a different programming language that I do not know anything about. How can I use these functions in my program? I'm afraid that if I try to rewrite them in Visual Basic I'll make mistakes that I can't detect. To be complete, I'm not using screen graphics so I really need a mathemathical solution.
Ok i have a Form with the following
Private Sub frmMain_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
txtNotepad.Text = LoadFile("notes.txt")
[code].....
I'm trying to write a simple game ui, it is grid/tile based, and i have the grid built using grid column and row definitions and I'm successfully placing objects in various grid locations. I am currently stuck as trying to build the player object. I want a single object reference to represent the various components of the players piece.
Currently I am using a polygon to represent the piece on the grid. Eventually I want to replace this with images or something. I want to add in properties for what weapon and armor it has equipped I want properties for health
Essentially in code i want something like this
dim player1 as new playerobject
player1.polygon.points = 0,0 60,30 0,60
player1.health = 100
[Code]....
I can instantiate all this as separate variables etc, but I'd like to have a singular reference that contains all the variables, properties, objects, controls etc.
I'm using vb .net in vs 2010 (and no, I'm not looking to write in something else)
I'm trying to write a simple game ui, it is grid/tile based, and i have the grid built using grid column and row definitions and I'm successfully placing objects in various grid locations.I am currently stuck as trying to build the player object. I want a single object reference to represent the various components of the players piece.
Currently I am using a polygon to represent the piece on the grid. Eventually I want to replace this with images or something.I want to add in properties for what weapon and armor it has equipped I want properties for health Essentially in code i want something like this
dim player1 as new playerobject
player1.polygon.points = 0,0 60,30 0,60
player1.health = 100
player1.weapon = "axe"
etc
I can instantiate all this as separate variables etc, but I'd like to have a singular reference that contains all the variables, properties, objects, controls etc.I'm using vb .net in vs 2010.
I've created a polygon shape and filled which fills blue on startup.Upon toggling a check box it should be filled yellow.It doesn't go yellow (unless i step through in debugging).
[Code]...
I am writing a program wherein the user draws shapes by clicking a button for the desired shape and then clicking on points on the drawing area. I cannot figure out how to store four clicked points to create a foursided polygon. I read many articles that say use the "mousedown" command and store points in a list, I have tried but it's not working for me. To summarize, I need the user to click the polygon button, go to the drawing area, click four points and have a foursided polygon created.
View 6 RepliesWhen i run the program i am getting the following error in this line TextBox1.Text &= "File Created: " & FullPath & vbCrLf"Cross-thread operation not valid: Control 'TextBox1' accessed from a thread other than the thread it was created on."
View 13 RepliesI'm creating a Client Server application which involves theServer running some scripts in clients and getting back results in an automated way. In Server, other than Main thread, i have 2 worker threads, a) one monitoring response from clients and b) the other scheduling next available job to respective client which executes that job. The issue here is ,I want these worker threads to write the status of their work in the UI(which comes under Main Thread). Also i need to write things in worker thread in a Data table and Rich Text Box in Main thread. But, I can't do so, since it has been blocked to access one thread's function or property directly from others. Is there any work around to do this?
View 8 Replies