I have a vb.net application that I want to be made a) visible and b) topmost when the activewindow is set to my requirements - this part I have covered off fine.
What I want to be able to do is to use the backgroundworker to actively monitor this on a continuous loop - again I have covered this off fine.
The problem I am having is that when I am selecting a combobox, I cannot make a selection due to interference from the bgw - almost like when I click on the combobox to show the list, the bgw seems to almost do a click away from the combobox closing the list.
Any help would greatly be appreciated.
Here is my code:
Private Delegate Sub progressDelegate()
Private Sub frmApp_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Me.bgwActiveWindow.RunWorkerAsync()
End Sub
Private Sub bgwActiveWindow_DoWork(ByVal sender As System.Object, ByVal e As System.ComponentModel.DoWorkEventArgs) Handles bgwActiveWindow.DoWork
Dim CheckWindow As progressDelegate
CheckWindow = New progressDelegate(AddressOf SetAppTopMost)
Me.Invoke(CheckWindow)
System.Threading.Thread.Sleep(100)
End Sub
Private Sub SetAppTopMost()
Dim bol As Boolean
If getActiveWindowTitle.IndexOf("Microsoft Outlook") <> -1 Or _
getActiveWindowTitle.IndexOf(My.Settings.AppName) <> -1 Then
bol = True
Else
bol = False
End If
Me.Visible = bol
Me.TopMost = bol
End Sub
Private Sub bgwActiveWindow_RunWorkerCompleted(ByVal sender As Object, ByVal e As System.ComponentModel.RunWorkerCompletedEventArgs) Handles bgwActiveWindow.RunWorkerCompleted
bgwActiveWindow.RunWorkerAsync()
End Sub
as Praveen mentioned, check the state before setting it, to prevent setting focus to the window again. also, don't recreate the backworker thread each time:
Imports System.ComponentModel
Private Sub bgwActiveWindow_DoWork(ByVal sender As Object, ByVal e As DoWorkEventArgs) Handles bgwActiveWindow.DoWork
Do
' backworker code
Threading.Thread.Sleep(1000)
Loop While True
End Sub
of course, you'll either have to implement the 'supportscancellation' junk, or simple set a flag in your main thread and poll that on each loop and exit/break if you want to cancel.
you could also use a timer, which won't lock the thread.
i think you should add an additional check in your SetAppTopMost sub.
if Me.Visible = True then exit sub
This line should be 1st line. Since you are trying to show the form every 100ms, you are loosing focus.
Related
I'm struggling to make the MSDN code sample for the Control.VisibleChanged event work: I don't see the MsgBox.
Private Sub Button_HideLabel(ByVal sender As Object, ByVal e As EventArgs)
myLabel.Visible = False
End Sub 'Button_HideLabel
Private Sub AddVisibleChangedEventHandler()
AddHandler myLabel.VisibleChanged, AddressOf Label_VisibleChanged
End Sub 'AddVisibleChangedEventHandler
Private Sub Label_VisibleChanged(ByVal sender As Object, ByVal e As EventArgs)
MessageBox.Show("Visible change event raised!!!")
End Sub 'Label_VisibleChanged
You need to "wire up" the events to the event handlers.
To start with, to get the code in HideLabel_Click to be called you need it to respond to a click on the button named "HideLabel".
There are two ways to do that: you can use AddHandler or the Handles clause.
To demonstrate the latter:
Option Strict On
Public Class Form1
Private Sub HideLabel_Click(sender As Object, e As EventArgs) Handles HideLabel.Click
myLabel.Visible = False
End Sub
Private Sub myLabel_VisibleChanged(sender As Object, e As EventArgs) Handles myLabel.VisibleChanged
MessageBox.Show("Visible change event raised!!!")
End Sub
End Class
However, you will notice that the message is shown even before the form appears. That is because of what goes on behind the scenes to create the form.
To avoid that happening, you can add the handler after the form has been shown:
Option Strict On
Public Class Form1
Private Sub HideLabel_Click(sender As Object, e As EventArgs) Handles HideLabel.Click
myLabel.Visible = False
End Sub
Private Sub myLabel_VisibleChanged(sender As Object, e As EventArgs)
MessageBox.Show("Visible change event raised!!!")
End Sub
Private Sub Form1_Shown(sender As Object, e As EventArgs) Handles MyBase.Shown
AddHandler myLabel.VisibleChanged, AddressOf myLabel_VisibleChanged
End Sub
End Class
Another way, in VB2015 and later, is to use a "lambda expression" instead of a separate method, although then you cannot disassociate the handler from the event with RemoveHandler:
Option Strict On
Public Class Form1
Private Sub HideLabel_Click(sender As Object, e As EventArgs) Handles HideLabel.Click
myLabel.Visible = False
End Sub
Private Sub Form1_Shown(sender As Object, e As EventArgs) Handles MyBase.Shown
AddHandler myLabel.VisibleChanged, Sub() MessageBox.Show("Visible change event raised!!!")
End Sub
End Class
Craig was kind enough to [and I quote verbatim] call attention to the importance of Option Strict when you add handlers manually using AddHandler. Without it, the "relaxed delegate convention" may allow adding handlers which don't exactly match the event signature that you won't be able to remove later.
Having said that, Option Strict On isn't a complete safeguard: notice how my last example compiles and works even with the wrong method signature for the handler.
[I suspect that the MSDN code sample was first created in C# as part of a larger example, so some parts have been lost in the translation and excerption.]
I get this is old but came across this post when looking for more information on VisibleChanged and couldn't help but notice that the accept answer may be misleading. If you are using a designer to create your Form and place objects on it, then the accepted answer will be fine. In fact you can get rid of the addHandler because the designer handles that for you. All you would need to do is use a handles clause with your label.
Private Sub Button_HideLabel(ByVal sender As Object, ByVal e As EventArgs) Handles Button1.Click
myLabel.Visible = False
End Sub 'Button_HideLabel
Private Sub Label_VisibleChanged(ByVal sender As Object, ByVal e As EventArgs) Handles myLabel.VisibleChanged
MessageBox.Show("Visible change event raised!!!")
End Sub 'Label_VisibleChanged
Where the issue lies with the accepted answer is if you arn't using a designer. Adding handle clauses to "wire up" simply won't work (we can make it work and if anyone is interested in that I'll be happy to post a code snippet of that, but it's not how the accepted answer lays it out). In your case all you need to do is call AddVisibleChangedEventHandler() to set up the handler. that's it. you could have done this by calling it in MyBase.Load
Private Sub Load_Form(ByVal sender As Object, ByVal e As EventArgs) Handles MyBase.Load
AddVisibleChangedEventHandler()
End Sub
Private Sub Button_HideLabel(ByVal sender As Object, ByVal e As EventArgs)
myLabel.Visible = False
End Sub 'Button_HideLabel
Private Sub Label_VisibleChanged(ByVal sender As Object, ByVal e As EventArgs)
MessageBox.Show("Visible change event raised!!!")
End Sub 'Label_VisibleChanged
Private Sub AddVisibleChangedEventHandler()
AddHandler myLabel.VisibleChanged, AddressOf Label_VisibleChanged
End Sub
Once again I know this is dated but couldn't help but notice that (more or less assuming) that you are trying to get a msgBox to appear when you click a label. That is you click a label and then toggled the visibility of another label. The other label is the one where the event handler is on for visibility change. So that inevitably gets called when clicking the original label. IF you only want this msgBox to appear when clicking that label and not when the form loads as well, you should change the addHandler statement so that you are adding a handler on the click event.
Private Sub Load_Form(ByVal sender As Object, ByVal e As EventArgs) Handles MyBase.Load
AddVisibleChangedEventHandler()
End Sub
Private Sub Label_VisibleChanged(ByVal sender As Object, ByVal e As EventArgs)
MessageBox.Show("Visible change event raised!!!")
End Sub 'Label_VisibleChanged
Private Sub AddVisibleChangedEventHandler()
AddHandler otherLabel.Click, AddressOf Label_VisibleChanged
End Sub 'AddVisibleChangedEventHandler
Also Option Strict On has nothing to do with addhandler (From my understanding, could be wrong. please enlighten me if that is the case). Option Strict On is only checking to see that you arn't implicitly typecasting. So for example:
Dim a As Double
Dim b As Integer
a = 10
b = a
results in an error when Option Strict is On but is totally legal if it is off. So in the case of you leaving off the handles clause, you'll never be implicitly typecasting and therefore is not needed.
Hope this helps anyone who sees this question
I have come to learn that a module level variable's value will not be altered until a sub routine that changed it exits.
StopBackgroundWorker1 = True
Thread.Sleep(1500)
If BackgroundWorker1Complete = False Then
Exit Sub
End If
in this example, I added a long delay for testing. I'm simply trying to stop and start a background worker safely with vb 2017 new background worker class.
The example above with "StopBackgroundWorker1 = True", I was hoping to stop the worker at a safe place and then continue within that sub with other code.
But what is happening is that the "StopBackgroundWorker1 = True" is not being set "True" until the sub exits.
There must be another way to do what I am trying to do, please help
Ok here is a complete example,
Imports System.ComponentModel
Imports System.Threading
Public Class Form1
Private flag As Boolean = False
Dim Completed As Boolean = False
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
BackgroundWorker1.RunWorkerAsync()
End Sub
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
flag = True
'Do
' do loop never see's a true flag
'Loop Until Completed
Thread.Sleep(500)
If Completed = True Then
Label1.BackColor = Color.Red
End If
End Sub
Private Sub BackgroundWorker1_DoWork(sender As Object, e As System.ComponentModel.DoWorkEventArgs) Handles BackgroundWorker1.DoWork
Do
Thread.Sleep(25)
Loop Until flag
End Sub
Private Sub BackgroundWorker1_RunWorkerCompleted(sender As Object, e As
RunWorkerCompletedEventArgs) Handles BackgroundWorker1.RunWorkerCompleted
Completed = True
End Sub
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles
Button2.Click
Label1.Text = flag.ToString
End Sub
End Class
Now the concept is if you hit button1 and wait for background worker to complete, it should turn lable1 red. but it doesn't. The do loop looking for a true flag will spin forever locking the form up.
I have determined with this example that the flag is not set to true until you exit the sub. Hit Button1 again and lable1 turns red.
Thanks in advance for any answers.
This doesn't answer your question per se but I want to post a large code snippet so I'll post it as an answer. It demonstrates that what you think is the problem is not the problem, i.e. that a field's value changes as soon as you change it, even if that change is made from a BackgroundWorker.DoWork event handler.
Create a new Windows Forms application project, add a Button, a Label and a BackgroundWorker to your form and then paste in this code over the default code of the form:
Imports System.ComponentModel
Imports System.Threading
Public Class Form1
Private flag As Boolean
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
BackgroundWorker1.WorkerReportsProgress = True
BackgroundWorker1.RunWorkerAsync()
End Sub
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Label1.Text = flag.ToString()
End Sub
Private Sub BackgroundWorker1_DoWork(sender As Object, e As System.ComponentModel.DoWorkEventArgs) Handles BackgroundWorker1.DoWork
Thread.Sleep(5000)
flag = True
BackgroundWorker1.ReportProgress(0)
Thread.Sleep(5000)
End Sub
Private Sub BackgroundWorker1_ProgressChanged(sender As Object, e As ProgressChangedEventArgs) Handles BackgroundWorker1.ProgressChanged
Label1.BackColor = Color.Green
End Sub
Private Sub BackgroundWorker1_RunWorkerCompleted(sender As Object, e As RunWorkerCompletedEventArgs) Handles BackgroundWorker1.RunWorkerCompleted
Label1.BackColor = Color.Red
End Sub
End Class
Run the project and, when the form appears, start clicking the Button at a pace of a few times per second. You'll see that the value of the flag field, as displayed on the Label, changes from False to True as soon as the code to set it is executed in the DoWork event handler. The Label will turn green when that happens, so it's easy to spot. You'll know that it didn't wait until the DoWork event handler completes because the Label will turn red at that point.
EDIT: Now that you have provided all the relevant information, the issue is obvious. As I have already said, the moment you set a variable, that is the value of that variable. There's no waiting because there cannot be any waiting because there's nowhere to store a temporary value for the variable.
The reason that it looks otherwise is that your test code is faulty. If you use the debugger then you will see how. When you use a BackgroundWorker, the DoWork event handler is executed on a secondary thread but the RunWorkerCompleted event handler is executed on the UI thread. That means that your DoWork event handler can execute at the same time as your Click event handler for Button1 because they are on different threads, but the RunWorkerCompleted event handler cannot run at the same time, so it has to wait until the Click event handler completes before it can be executed. That means that the code to set the Completed field doesn't get executed until the Click event handler completes. It's not that the field value doesn't change when it's set but rather that it doesn't actually get set. If you place breakpoints on the two lines that access that Completed field then you'll see that.
The mistake you're making is trying to do something in that Click event handler after the DoWork event handler completes. That's wrong. That's exactly what the RunWorkerCompleted event handler is for. That's where you do UI work after the background work completes.
Also, you can get rid of that flag variable. Cancellation functionality is built into the BackgroundWorker class. Look at the CancelAsync method and the CancellationPending property.
Many thanks to "jmcilhinney" for his insights! I have figured out the code I was looking for!
This code allows me to stop and start a background thread safely by allowing the background thread to finish completely before restarting.
During the time that the background thread is stopped, user actions can perform operations without the worry of cross-threading or with thread.abort garbled code conditions.
Finally, stress-free threading!
I wish I could find the doc on MSDN that I read that stated the await async method was far superior to task.run but that's another argument.
This may not be the best code in the world but it works!
And in light of trying to rewrite all code in my project with async and await I'll stick with this!
Public Class Form1
Private flag As Boolean = False
Dim Completed As Boolean = False
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
BackgroundWorker1.RunWorkerAsync()
End Sub
Private Async Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
flag = True
Await Task.Run(Sub()
Do
Loop Until Completed
End Sub)
If Completed = True Then
Label1.BackColor = Color.Red
End If
BackgroundWorker1.RunWorkerAsync()
End Sub
Private Sub BackgroundWorker1_DoWork(sender As Object, e As System.ComponentModel.DoWorkEventArgs) Handles BackgroundWorker1.DoWork
Do
Thread.Sleep(250)
Loop Until flag
End Sub
Private Sub BackgroundWorker1_RunWorkerCompleted(sender As Object, e As
RunWorkerCompletedEventArgs) Handles BackgroundWorker1.RunWorkerCompleted
Completed = True
End Sub
End Class
For all of the academics out there this code is more appropriate.
Imports System.ComponentModel
Imports System.Threading
Public Class Form1
Private Completed As Boolean = False
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
BackgroundWorker1.WorkerSupportsCancellation = True
BackgroundWorker1.RunWorkerAsync()
End Sub
Private Async Sub Button1_Click(sender As Object, e As EventArgs) Handles
Button1.Click
BackgroundWorker1.CancelAsync()
Await Task.Run(Sub()
Do
Loop Until Completed
End Sub)
If Completed = True Then
Label1.BackColor = Color.Red
End If
BackgroundWorker1.RunWorkerAsync()
End Sub
Private Sub BackgroundWorker1_DoWork(sender As Object, e As System.ComponentModel.DoWorkEventArgs) Handles BackgroundWorker1.DoWork
Do
Thread.Sleep(250)
Loop Until BackgroundWorker1.CancellationPending
End Sub
Private Sub BackgroundWorker1_RunWorkerCompleted(sender As Object, e As RunWorkerCompletedEventArgs) Handles BackgroundWorker1.RunWorkerCompleted
Completed = True
End Sub
End Class
I have read other posts about this but I still can't seem to get it to work right.
Whenever my BackgroundWorker begins to do work, my function API.CheckForUpdate causes the GUI to hang. I can't click on anything. It only freezes for half a second, but is enough to notice.
How can I fix this? Should I dive deeper into API.CheckForUpdate and run individual threads on particular statements, or can I just have an all-inclusive thread that handles this? API.CheckForUpdate does not reference anything in Form1.
Also, I presume Form1_Load is not the best place to put the RunWorkerAsync call. Where is a better spot?
'Declarations
Dim ApplicationUpdate As BackgroundWorker = New BackgroundWorker
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
ApplicationUpdate.WorkerSupportsCancellation = True
ApplicationUpdate.WorkerReportsProgress = True
AddHandler ApplicationUpdate.DoWork, AddressOf ApplicationUpdate_DoWork
AddHandler ApplicationUpdate.ProgressChanged, AddressOf ApplicationUpdate_ProgressChanged
AddHandler ApplicationUpdate.RunWorkerCompleted, AddressOf ApplicationUpdate_RunWorkerCompleted
ApplicationUpdate.RunWorkerAsync()
End Sub
Private Sub ApplicationUpdate_DoWork(ByVal sender As Object, ByVal e As DoWorkEventArgs)
'Check for an update (get the latest version)
Dim LatestVersion = API.CheckForUpdate
End Sub
Private Sub ApplicationUpdate_ProgressChanged(ByVal sender As Object, ByVal e As ProgressChangedEventArgs)
'Nothing here
End Sub
Private Sub ApplicationUpdate_RunWorkerCompleted(ByVal sender As Object, ByVal e As RunWorkerCompletedEventArgs)
'Work completed
MsgBox("Done")
End Sub
Its not a background worker Fix but if you don't mind walking around and not finding the answer, you can code like so:
Keep in mind when you first Start a Thread and you are coding in a Model you MUST pass (me) into the initial thread because of VB having a concept of "Default Form Instances". For every Form in the application's namespace, there will be a default instance created in the My namespace under the Forms property.
and that is just adding an additional parameter like so
----------------------/ Starting Main Thread /-----------------------------------
Private Sub FindCustomerLocation()
Dim Findcontractor_Thread As New Thread(AddressOf **FindContractor_ThreadExecute**)
Findcontractor_Thread.Priority = ThreadPriority.AboveNormal
Findcontractor_Thread.Start(me)
End Sub
------------------/ Running Thread /---------------
Private Sub **FindContractor_ThreadExecute**(beginform as *NameOfFormComingFrom*)
Dim threadControls(1) As Object
threadControls(0) = Me.XamDataGrid1
threadControls(1) = Me.WebBrowserMap
**FindContractor_WorkingThread**(threadControls,beginform) ' ANY UI Calls back to the Main UI Thread MUST be delegated and Invoked
End Sub
------------------/ How to Set UI Calls from a Thread / ---------------------
Delegate Sub **FindContractor_WorkingThread**(s As Integer,beginform as *NameOfFormComingFrom*)
Sub **FindContractor_WorkingThreadInvoke**(ByVal s As Integer,beginform as *NameOfFormComingFrom*)
If beginform.mouse.InvokeRequired Then
Dim d As New FindContractor_WorkingThread(AddressOf FindContractor_WorkingThreadInvoke)
beginform.Invoke(d, New Object() {s,beginform})
Else
beginform.Mouse.OverrideCursor = Cursors.Wait
'Do something...
beginform.Mouse.OverrideCursor = Nothing
End If
End Sub
Sources From Pakks Answer Tested!
Try starting the process outside the Load event. Create a Timer and start it on the Load event, and then handle the event for the tick:
Private Sub Timer1_Tick(sender As Object, e As EventArgs) Handles Timer1.Tick
Timer1.Enabled = False
ApplicationUpdate.RunWorkerAsync()
End Sub
I'm using a DO interation to loop a function I'm using to test for internet connectivity. The code is working fine, except that when one of the tests is satisfied the loop stops. I want this to continue in the background while the program is running. How can I get this to work?
Private Sub checkInternet()
Dim InetChecker As Boolean
InetChecker = CheckForInternetConnection()
Do While LabelCount.Text <> ""
Thread.Sleep(10)
If InetChecker = True Then
Dim image = My.Resources.greenbar
PictureBox4.Image = image
Else
Thread.Sleep(10)
Dim image = My.Resources.redbar
PictureBox4.Image = image
'NoInetConnError.Show()
End If
Loop
End Sub
Your assistance would be greatly appreciated, thanks.
Put a BackgroundWorker on your form (you will find it in the Components section of the Toolbox).
In the Properties window set WorkerReportsProgress to True for your BackgroundWorker.
Insert the following code to your form
Private connected As Boolean
Private Sub BackgroundWorker1_DoWork(ByVal sender As Object, ByVal e As DoWorkEventArgs) _
Handles BackgroundWorker1.DoWork
While True
Dim online = CheckForInternetConnection()
If online <> connected Then
connected = online
BackgroundWorker1.ReportProgress(CInt(online))
End If
Thread.Sleep(500)
End While
End Sub
Private Sub BackgroundWorker1_ProgressChanged(ByVal sender As Object, ByVal e As ProgressChangedEventArgs) _
Handles BackgroundWorker1.ProgressChanged
Dim online As Boolean = CBool(e.ProgressPercentage)
If online Then
PictureBox4.Image = My.Resources.greenbar
Else
PictureBox4.Image = My.Resources.redbar
End If
End Sub
Private Sub Form_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) _
Handles MyBase.Load
' Start the background worker
BackgroundWorker1.RunWorkerAsync()
End Sub
Note that Sub BackgroundWorker1_DoWork runs on a separate thread and does not freeze your form while it is running.
It would be best to do something like this in a Timer and not in a loop.
Private Sub Timer1_Tick(ByVal sender As Object, ByVal e As EventArgs) Handles Timer1.Tick
If CheckForInternetConnection Then
PictureBox4.Image = My.Resources.greenbar
Else
PictureBox4.Image = My.Resources.redbar
End If
End Sub
If you have access to .Net framework 3+ then you could use the DispatcherTimer class which essentially creates an interval (set at whatever length you require) which you can handle the tick event for. When the tick event is raised, you can do your internet connection check.
Modifying the MSDN example for your situation, you could do something like this:
' DispatcherTimer setup
dispatcherTimer = New Threading.DispatcherTimer()
AddHandler dispatcherTimer.Tick, AddressOf dispatcherTimer_Tick
dispatcherTimer.Interval = New TimeSpan(0,0,1) ' Or however long you want
dispatcherTimer.Start()
Private Sub dispatcherTimer_Tick(ByVal sender As Object, ByVal e As EventArgs)
' Checks to see whether an internet connection is still available etc
checkInternet()
' Forcing the CommandManager to raise the RequerySuggested event
CommandManager.InvalidateRequerySuggested()
End Sub
Hi guys Hope all is well
I am wondering(struggling) the following:
I have 5 flowLayoutPanels and 5 PictureBoxes i want to be able to move anyone of the picture boxes over anyone the FLP at run time and have the layout panel add it to FLP.controls.Add()....
I've been at it for Hours and now ill swallow my pride -
I have done the following To get it working, but here i have to manually specify which PixBox intersects with which FLP and i dont want 25 if statements
Private Sub cpbPic1_MouseUp(ByVal sender As System.Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles cpbPic1.MouseUp
If (flpDock1.HasChildren = False) Then 'Test to see if panel is filled
If CBool(CustomPictureBox.IntersectingObjects(cpbPic1, flpDock1)) Then
flpDock1.Controls.Add(cpbPic1) 'Add Pic to Panel
End If
End Sub
cpb: CustomPictureBox
you could always do this:
Private Sub cpbPic1_MouseUp(ByVal sender As System.Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles cpbPic1.MouseUp, cpbPic2.MouseUp, cpbPic3.MouseUp,cpbPic4.MouseUp,cpbPic5.MouseUp
If Not flpDock1.HasChildren Then 'Test to see if panel is filled
If CBool(CustomPictureBox.IntersectingObjects(TryCast(sender,CustomPictureBox), flpDock1)) Then
flpDock1.Controls.Add(TryCast(sender,CustomPictureBox)) 'Add Pic to Panel
End If
End Sub
This will reduce the amount of code you'll have to write significantly, you can further reduce this amount if you think about how to utilize the fact that the event handler passes the Object which raises the flag, like I did here.
Also you can use arbitrary big amount (i think) of objects in a handler as long as they raise the same event
well this can be a work around for what you want to do.
you also have to enable allowdrop to the flowpanels
Private Function FindControl(ByVal ControlName As String, ByVal CurrentControl As Control) As Control
' get the control you need
Dim ctr As Control
For Each ctr In CurrentControl.Controls
If ctr.Name = ControlName Then
Return ctr
Else
ctr = FindControl(ControlName, ctr)
If Not ctr Is Nothing Then
Return ctr
End If
End If
Next ctr
End Function
Private Sub me_DragEnter(sender As Object, e As DragEventArgs) Handles FLP1.DragEnter,FLP2.DragEnter,FLP3.DragEnter
' call the copy effect
If (e.Data.GetDataPresent(DataFormats.Text)) Then
e.Effect = DragDropEffects.Copy
End If
End Sub
Private Sub me_DragDrop(sender As Object, e As DragEventArgs) Handles FLP1.DragDrop,FLP2.DragDrop,FLP3.DragDrop
' get the FLp you're gonna drop the control onto
Dim c As control =FindControl(e.Data.GetData(DataFormats.Text), me)
sender.Controls.Add(c)
end sub
Private Sub Pictureboxs_MouseDown(sender As Object, e As MouseEventArgs) Handles Label1.MouseDown, PB.MouseDown
sender.DoDragDrop(sender.Name, DragDropEffects.Copy)
End Sub
hope that this helps you :) (sorry for my bad english)