I have a PC in a corporate production environment and need to make sure the same program loads over and over. I upgraded to Windows 7 and my start-up program keeps losing focus because of MacAfee. I tried to uninstall MacAfee but it's an enterprise version and it won't let me. I tried to do some programming in my vb.net application to regain focus but nothing has worked.
Here's a picture of how the program boots up - notice the form is a lighter color and has lost focus:
http://i.imgur.com/Qwlzuzw.jpg
Here's a picture of how the form SHOULD load up after I click on it with the mouse to fix it - notice the darker color of the form:
http://i.imgur.com/DuLyCsC.jpg
Here's why I think MacAfee is the problem - if I alt tab, the MacAfee updater icon shows up:
http://i.imgur.com/opgOWHW.jpg
Any ideas to solve my problem programmatically or otherwise?
Here's sample code on a timer that gets the foreground window handle, if it's not Me, make it Me
Private Declare Function GetForegroundWindow Lib "user32" () As IntPtr
Private Declare Function SetForegroundWindow Lib "user32" (ByVal hwnd As IntPtr) As Long
Private Sub Timer1_Tick(sender As System.Object, e As System.EventArgs) Handles Timer1.Tick
Dim focusedWindow As System.IntPtr
focusedWindow = GetForegroundWindow()
If Not Me.Handle.Equals(focusedWindow) Then
SetForegroundWindow(Me.Handle)
End If
End Sub
In form1.shown sub write this:
For i = 0 To 100
Me.Activate()
Next
This will try 100 times to focus on your form when it shows up.
Related
I am currently working on a TextBox using VB.NET 2015 that is read-only and only inserts characters by a button click event. I want to hide or disable the iBeam inside the TextBox to let the user know that it is only accessible by the button click and not by manual typing on the actual keyboard. I have tried changing its ReadOnly property to True and cursor property to cursors other than the iBeam but they don't seem to work.
Is there another way, may it be a code or a property that disables the iBeam in the TextBox when its accessed?
This image is my example of an on-screen keyboard. As you can see, the iBeam on the TextBox is visible as soon as I click on one of the on-screen keys.
Use the HideCaret() API call from the GotFocus() event of your TextBox:
Private Declare Function HideCaret Lib "user32.dll" (ByVal hWnd As IntPtr) As Boolean
Private Sub TextBox1_GotFocus(sender As Object, e As EventArgs) Handles TextBox1.GotFocus
HideCaret(TextBox1.Handle)
End Sub
I need to prevent the user of my console program from resizing the window, only allowing it to be changed programmatically. If the user changes the width, everything messes up. Also, I want to disable the maximise button. Are either of these possible in Console?
This answer neatly covers how to disable resizing a form in WinForms, but it won't work for Console.
I came up with a solution that prevents re-sizing of a console window application (either by dragging the corner border or by clicking on the maximize or minimize buttons). The following code is written in the form of a complete VB.Net console application (i.e., a Module):
Module Module1
Private Const MF_BYCOMMAND As Integer = &H0
Public Const SC_CLOSE As Integer = &HF060
Public Const SC_MINIMIZE As Integer = &HF020
Public Const SC_MAXIMIZE As Integer = &HF030
Public Const SC_SIZE As Integer = &HF000
Friend Declare Function DeleteMenu Lib "user32.dll" (ByVal hMenu As IntPtr, ByVal nPosition As Integer, ByVal wFlags As Integer) As Integer
Friend Declare Function GetSystemMenu Lib "user32.dll" (hWnd As IntPtr, bRevert As Boolean) As IntPtr
Sub Main()
Dim handle As IntPtr
handle = Process.GetCurrentProcess.MainWindowHandle ' Get the handle to the console window
Dim sysMenu As IntPtr
sysMenu = GetSystemMenu(handle, False) ' Get the handle to the system menu of the console window
If handle <> IntPtr.Zero Then
DeleteMenu(sysMenu, SC_CLOSE, MF_BYCOMMAND) ' To prevent user from closing console window
DeleteMenu(sysMenu, SC_MINIMIZE, MF_BYCOMMAND) 'To prevent user from minimizing console window
DeleteMenu(sysMenu, SC_MAXIMIZE, MF_BYCOMMAND) 'To prevent user from maximizing console window
DeleteMenu(sysMenu, SC_SIZE, MF_BYCOMMAND) 'To prevent the use from re-sizing console window
End If
Do Until (Console.ReadKey.Key = ConsoleKey.Escape)
'This loop keeps the console window open until you press escape
Loop
End Sub
End Module
I based this answer off of the Stack Overflow question/answer: "Disable the maximize and minimize buttons of a c# console [closed]"
Please let me know if this doesn't work for you. Good luck!
I wanted to comment on the accepted answer, but I lack reputation...
To prevent the console window from resizing when you snap it to a corner, you can use
Console.SetBufferSize(80, 24) ' or whatever size you're using...
This is my first question, please be nice. Oh, and I'm not a native english speaker. :)
I've discovered some weird bug in my application. I've created a TextBox control with a button in it (code below). Following these steps will make the button disappear.
Start windows media player with some music (or video)
Start the application
Click in TextBox control and hold down left mouse button
Move your cursor around like crazy
Woosh... Button disappears.
This will not happen when you closed or paused your windows media player. I was able to reproduce this bug on a different system (Windows 7 and Windows 10). This is totally weird, because it doesn't seem logical. Windows is doing crazy stuff with the windows media player...
I'm not sure if there's a workaround. Can anybody help me with this or should I ask on Microsoft forums? I've tried to call "UpdateButton" while selection changed, but I wasn't successful.
Public Class TextBoxEx
Inherits TextBox
Const BUTTON_WIDTH As Integer = 18
Const EM_SETMARGINS As Integer = &HD3
Const EC_RIGHTMARGIN As Integer = &H2
<Runtime.InteropServices.DllImport("user32.dll", SetLastError:=True)> _
Private Shared Function SendMessage(ByVal hWnd As IntPtr, ByVal Msg As UInteger, ByVal wParam As Integer, ByVal lParam As Integer) As IntPtr
End Function
Private btnCommand As Button
Public Sub New()
btnCommand = New Button
btnCommand.Cursor = Cursors.Default
btnCommand.Image = My.Resources.iconCancel
Me.Controls.Add(btnCommand)
Call UpdateButton()
End Sub
Private Sub UpdateButton()
Dim rightMargin As Integer = (BUTTON_WIDTH + 1) << 16
btnCommand.Size = New Size(BUTTON_WIDTH, Me.ClientSize.Height)
btnCommand.Location = New Point(Me.ClientSize.Width - BUTTON_WIDTH, 0)
Call SendMessage(Me.Handle, EM_SETMARGINS, EC_RIGHTMARGIN, rightMargin)
End Sub
Protected Overrides Sub OnResize(e As System.EventArgs)
MyBase.OnResize(e)
Call UpdateButton()
End Sub
End Class
I'm working on an encryption program and it uses a "PIN" to calculate some stuff for the encryption. I have a textbox where the user can insert the "PIN". I'd like to prevent people from entering anything but numbers. I added this on the KeyPress event:
If Not Char.IsControl(e.KeyChar) Then
If Not Char.IsNumber(e.KeyChar) Then
MsgBox("Invalid character", , "WARNING!")
TextBox3.Clear()
End If
End If
It shows the msgbox and it doesn't write to the textbox until i close th emsgbox. The typed character appears in the textbox. When I write another one it works the same as before, but it only replaces the last character instead of writing another one. Is there something I'm missing because that looks like a bug to me?
Set the ES_NUMBER windows style for your TextBox:
Public Class Form1
Public Const GWL_STYLE As Integer = (-16)
Public Const ES_NUMBER As Integer = &H2000
Public Declare Function GetWindowLong Lib "user32" Alias "GetWindowLongA" _
(ByVal handle As IntPtr, ByVal nIndex As Integer) As Integer
Public Declare Function SetWindowLong Lib "user32" Alias "SetWindowLongA" _
(ByVal handle As IntPtr, ByVal nIndex As Integer, ByVal dwNewLong As Integer) As Integer
Public Sub SetNumbersOnlyTextBox(ByVal TB As TextBox)
SetWindowLong(TB.Handle, GWL_STYLE, GetWindowLong(TB.Handle, GWL_STYLE) Or ES_NUMBER)
End Sub
Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
SetNumbersOnlyTextBox(TextBox3)
End Sub
End Class
It shows the msgbox and it doesn't write to the textbox until i close th emsgbox.
Yes, that's what modal dialogs do. They block the caller from updates until closed. That's the point; the user cannot interact with the parent until they clear the modal child.
Why not simply clear the textbox first? Better yet; don't show an annoying dialog at all. Simply disallow the user from entering invalid characters by setting e.Handled to true. However, it's a bit trickier than it sounds as you need to allow for the backspace and delete keys, disable pasting, etc.
Here's an example of a NumericTextbox: http://msdn.microsoft.com/en-us/library/ms229644(v=vs.80).aspx
You just need to set the Handled property to true instead of clear:
e.Handled = True
As MarkPM notes above, if its a key you don't want you can set e.handle=true (as you intercept the key on the keypress event) to have the system eat it.
Along with this, in stead of a pop-up, you can have a label on the form that says "Only numbers can be entered here" or something like that. Set it up so that the color of the text is red. Also set it up so the label is not normally visible.
Finally, also in the keypress event, beyond setting e.handle=true for unwanted keys, when an unwanted key comes along make the label that says "Only numbers can be entered here" visible - you can also set up a timed event to turn the label's visibility off after a few seconds. You can also throw a Beep() into the mix if you like :-)
This is less invasive then a pop-up and moves things along nicely for the user.
Preface: I know this is an unusual/improper way to do this. I can do this with a "real" ShowDialog(), background worker/thread, and so on. I'm not looking for help doing it that way; I am trying to do specifically what I describe here, even if it is ugly. If this is impossible for X reason, please let me know though.
I have created a fancy progress dialog for some of our long running operations. I need to have this dialog shown on a new thread while having processing continue on the calling (UI in most cases) thread.
This has 3 real requirements:
Prevent user interaction with the calling form (similar to ShowDialog(this))
Keep the progress dialog above the main window (it can fall behind now)
Allow the main thread to continue processing
What I have looks like this (and works just fine so far, as far as running goes, except for those issues above):
Using ... ShowNewProgressDialogOnNewThread() ...
Logic
UpdateProgress() //static
Logic
UpdateProgress() //static, uses Invoke() to call dialog
...
End Using // destroys the form, etc
I have tried a few ways to do this:
ShowDialog() on BackgroundWorker / Thread
Action.BeginInvoke() which calls a function
ProgressForm.BeginInvoke(... method that calls ShowDialog... )
Wrapping main form in a class that implements IWin32Window so it can be called cross-threaded and passed to ShowDialog() - this one failed somewhere later one, but at least causes ShowDialog() to not barf immediately.
Any clues or wisdom on how to make this work?
Solution (For Now)
The call to EnableWindow is what did what I was looking for.
I do not experience any crashes at all
Changed to use ManualResetEvent
I set TopMost, because I couldn't always guarantee the form would end up on top otherwise. Perhaps there is a better way.
My progress form is like a splash screen (no sizing, no toolbar, etc), perhaps that accounts for the lack of crashes (mentioned in answer)
Here is another thread on the EnableWindow topic (didn't reference for this fix, tho)
Getting the progress window consistently displayed on top of the (dead) form is the difficult requirement. This is normally handled by using the Form.Show(owner) overload. It causes trouble in your case, WF isn't going to appreciate the owner form belonging to another thread. That can be worked around by P/Invoking SetWindowLong() to set the owner.
But now a new problem emerges, the progress window goes belly-up as soon as it tries to send a message to its owner. Somewhat surprisingly, this problem kinda disappears when you use Invoke() instead of BeginInvoke() to update progress. Kinda, you can still trip the problem by moving the mouse over the border of the disabled owner. Realistically, you'll have to use TopMost to nail down the Z-order. More realistically, Windows just doesn't support what you are trying to do. You know the real fix, it is at the top of your question.
Here's some code to experiment with. It assumes you progress form is called dlgProgress:
Imports System.Threading
Public Class ShowProgress
Implements IDisposable
Private Delegate Sub UpdateProgressDelegate(ByVal pct As Integer)
Private mOwnerHandle As IntPtr
Private mOwnerRect As Rectangle
Private mProgress As dlgProgress
Private mInterlock As ManualResetEvent
Public Sub New(ByVal owner As Form)
Debug.Assert(owner.Created)
mOwnerHandle = owner.Handle
mOwnerRect = owner.Bounds
mInterlock = New ManualResetEvent(False)
Dim t As Thread = New Thread(AddressOf dlgStart)
t.SetApartmentState(ApartmentState.STA)
t.Start()
mInterlock.WaitOne()
End Sub
Public Sub Dispose() Implements IDisposable.Dispose
mProgress.BeginInvoke(New MethodInvoker(AddressOf dlgClose))
End Sub
Public Sub UpdateProgress(ByVal pct As Integer)
mProgress.Invoke(New UpdateProgressDelegate(AddressOf dlgUpdate), pct)
End Sub
Private Sub dlgStart()
mProgress = New dlgProgress
mProgress.StartPosition = FormStartPosition.Manual
mProgress.ShowInTaskbar = False
AddHandler mProgress.Load, AddressOf dlgLoad
AddHandler mProgress.FormClosing, AddressOf dlgClosing
EnableWindow(mOwnerHandle, False)
SetWindowLong(mProgress.Handle, -8, mOwnerHandle)
Application.Run(mProgress)
End Sub
Private Sub dlgLoad(ByVal sender As Object, ByVal e As EventArgs)
mProgress.Location = New Point( _
mOwnerRect.Left + (mOwnerRect.Width - mProgress.Width) \ 2, _
mOwnerRect.Top + (mOwnerRect.Height - mProgress.Height) \ 2)
mInterlock.Set()
End Sub
Private Sub dlgUpdate(ByVal pct As Integer)
mProgress.ProgressBar1.Value = pct
End Sub
Private Sub dlgClosing(ByVal sender As Object, ByVal e As FormClosingEventArgs)
EnableWindow(mOwnerHandle, True)
End Sub
Private Sub dlgClose()
mProgress.Close()
mProgress = Nothing
End Sub
'--- P/Invoke
Public Shared Function SetWindowLong(ByVal hWnd As IntPtr, ByVal nIndex As Integer, ByVal dwNewLong As IntPtr) As IntPtr
If IntPtr.Size = 4 Then
Return SetWindowLongPtr32(hWnd, nIndex, dwNewLong)
Else
Return SetWindowLongPtr64(hWnd, nIndex, dwNewLong)
End If
End Function
Private Declare Function EnableWindow Lib "user32.dll" (ByVal hWnd As IntPtr, ByVal enabled As Boolean) As Boolean
Private Declare Function SetWindowLongPtr32 Lib "user32.dll" Alias "SetWindowLongW" (ByVal hWnd As IntPtr, ByVal nIndex As Integer, ByVal dwNewLong As IntPtr) As IntPtr
Private Declare Function SetWindowLongPtr64 Lib "user32.dll" Alias "SetWindowLongW" (ByVal hWnd As IntPtr, ByVal nIndex As Integer, ByVal dwNewLong As IntPtr) As IntPtr
End Class
Sample usage:
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Using dlg As New ShowProgress(Me)
For ix As Integer = 1 To 100
dlg.UpdateProgress(ix)
System.Threading.Thread.Sleep(50)
Next
End Using
End Sub
I know it's a bit dirty but can't you just do the work in the dialog??
I mean something like
Dialog.MyShowDialog(callback);
and do all the work in callback as well as the UI update.
That way you'll retain the ShowDialog behaivour while allowing different code to be called.
I wrote a blog post on this topic a while ago (dealing with splash forms, but the idea is the same). The code is in C#, but I will try to convert it an post it here (coming...).