Public Class Form1
Private _zkouska1 As New Bitmap("C:\Users\w\Desktop\zkouska1.gif")
Private _zkouska2 As New Bitmap("C:\Users\w\Desktop\zkouska2.gif")
Protected Overrides Sub OnPaint(ByVal e As System.Windows.Forms.PaintEventArgs)
MyBase.OnPaint(e)
e.Graphics.DrawImageUnscaled(New Bitmap(_zkouska1), 0, 0)
End Sub
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
MyNewSub()
End Sub
Sub MyNewSub()
BackColor = Color.Red
TransparencyKey = BackColor
End Sub
Private Sub Example_ControlAdded(ByVal sender As Object, ByVal e As System.Windows.Forms.ControlEventArgs) Handles Me.ControlAdded
AddHandler e.Control.MouseClick, AddressOf Example_MouseClick
End Sub
Private Sub Example_MouseClick(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Me.MouseClick
If True Then e.Graphics.DrawImageUnscaled(New Bitmap(_zkouska2), 0, 0) = True
End Sub
End Class
You haven't indicated specifically which lines are causing the issue, but the issue with this line:
If True Then e.Graphics.DrawImageUnscaled(New Bitmap(_zkouska2), 0, 0) = True
is that MouseEventArgs doesn't have a Graphics member. Perhaps the thing to do here is to use the Mouse_Clicked event to set a variable that keeps tracks of whether the mouse was clicked (and where), and use the Paint event to do the actual drawing.
So you would add a boolean variable to the class:
Private _clicked As Boolean
Change the MouseClicked event to something like this:
Private Sub Example_MouseClick(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Me.MouseClick
_clicked = True
End Sub
Add a Paint event and make that event so it's something like this:
Private Sub Form1_Paint(sender As System.Object, e As System.Windows.Forms.PaintEventArgs) Handles MyBase.Paint
If _clicked Then
e.Graphics.DrawImageUnscaled(New Bitmap(_zkouska2), 0, 0)
End If
End Sub
Related
i have two RadioButtons one for Light Blue and the other for Ghost White and a button to show the next Form (Form2)
i want to be able to check on a Radio Button and the backcolor of form2 changes to the checked Radio Button
this is what i have on my coding so far
Private Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
SecondForm.Show()
End Sub
Private Sub rbLightBlue_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles rbLightBlue.CheckedChanged
If rbLightBlue.Checked Then
SecondForm.BackColor = (Color.LightBlue)
End If
End Sub
Private Sub rbGhostWhite_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles rbGhostWhite.CheckedChanged
If rbGhostWhite.Checked Then
SecondForm.BackColor = (Color.GhostWhite)
End If
End Sub
The problem am having is making the background color change on Form2.
Any answer for this question will be very helpful.
I am not sure what you are doing, it probably has to do with how you are creating your SecondForm, this code does work, see if it helps you narrow it down.
Public Class Form1
Dim SecondForm As Form2 = New Form2
Private Sub rbLightBlue_CheckedChanged(sender As Object, e As EventArgs) Handles rbLightBlue.CheckedChanged
If DirectCast(sender, RadioButton).Checked Then
SecondForm.BackColor = Color.LightBlue
End If
End Sub
Private Sub rbGhostWhite_CheckedChanged(sender As Object, e As EventArgs) Handles rbGhostWhite.CheckedChanged
If DirectCast(sender, RadioButton).Checked Then
SecondForm.BackColor = Color.GhostWhite
End If
End Sub
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
SecondForm.Show()
End Sub
End Class
Could any body kindly give me code example how to capture datagridview cell keypress event?
Datagridview_keypress does not help.
Thanks
As per Fco Navarro's answer, except that using e.Control does not always work because e is passed in to the EditingControlShowing event ByVal meaning any changes to the control (eg changing the .Text property) are NOT reflected in the DataGridView. If you need to do anything with the actual TextBox control in your event handler, you can use DataGridView1.EditingControl instead of e.Control.
Private WithEvents txtNumeric As New DataGridViewTextBoxEditingControl
Private Sub DataGridView1_EditingControlShowing(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewEditingControlShowingEventArgs) Handles DataGridView1.EditingControlShowing
txtNumeric = CType(DataGridView1.EditingControl, DataGridViewTextBoxEditingControl)
End Sub
Private Sub txtNumeric_KeyPress(ByVal sender As Object, ByVal e As KeyPressEventArgs) Handles txtNumeric.KeyPress
txtNumeric.Text = txtNumeric.Text.ToUpper()
End Sub
Private WithEvents txtNumeric As New DataGridViewTextBoxEditingControl
Private Sub DataGridView1_EditingControlShowing(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewEditingControlShowingEventArgs) Handles DataGridView1.EditingControlShowing
txtNumeric = CType(e.Control, DataGridViewTextBoxEditingControl)
End Sub
Private Sub txtNumeric_KeyDown(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles txtNumeric.KeyDown
If (e.KeyData >= Keys.A And e.KeyData <= Keys.Z) Then
e.SuppressKeyPress = True
End If
End Sub
Try this:
Private Sub DataGridView1_EditingControlShowing(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewEditingControlShowingEventArgs) Handles DataGridView1.EditingControlShowing
If Me.DataGridView1.CurrentCell.ColumnIndex = 0 And Not e.Control Is Nothing Then
Dim tb As TextBox = CType(e.Control, TextBox)
AddHandler tb.KeyDown, AddressOf TextBox_KeyDown
AddHandler tb.KeyPress, AddressOf TextBox_KeyPress
End If
End Sub
Private Sub TextBox_KeyDown(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs)
If e.KeyCode = Keys.Space Then
flag = True
End If
End Sub
Private Sub TextBox_KeyPress(ByVal sender As System.Object, ByVal e As System.Windows.Forms.KeyPressEventArgs)
e.Handled = flag
flag = False
End Sub
Extracted from here.
I use the KeyUp event instead of KeyPress. The trick is to attach the handler event to the ActiveControl property of form when the cell has the active state.
Private Sub grid_CellBeginEdit(sender As Object, e As DataGridViewCellCancelEventArgs) Handles grid.CellBeginEdit
AddHandler Me.ActiveControl.KeyUp, AddressOf Cell_KeyUp
End Sub
Private Sub Cell_KeyUp(sender As Object, e As KeyEventArgs)
Console.WriteLine(sender.Text) 'content of cell
End Sub
If you want to use also RemoveHandler method, you can add a global variable to the class (using this variable instead of Me.ActiveControl) and call RemoveHandler for example into the CellEndEdit event of DataGridView.
if your using your gridview in asp.net (Website) its not possible. there is no keypress Event.
its possible indeed but you have to use JavaScript to make a postback on every keychanged (Client side). but this is not a nice programming style and should not be used (you are getting rly many postbacks which are slowing down the complete System).
if your using Windows forms: have a look at the answer from sysdragon.
hope this helps a bit.
best regards, noone
the following code work perfectly:
Private WithEvents txtmontant As DataGridViewTextBoxEditingControl
Private Sub DGdivers_EditingControlShowing(sender As Object, e As DataGridViewEditingControlShowingEventArgs) Handles DGdivers.EditingControlShowing
If DGdivers.CurrentCell.ColumnIndex = 1 Then
Dim txtmontant = CType(e.Control, DataGridViewTextBoxEditingControl)
AddHandler txtmontant.KeyPress, AddressOf txtmontant_keypress
Else
RemoveHandler txtmontant.KeyPress, AddressOf txtmontant_keypress
End If
End Sub
Private Sub txtmontant_keypress(sender As Object, e As KeyPressEventArgs) Handles txtmontant.KeyPress
If e.KeyChar = vbCr Then
DGdivers.Rows.Add()
Exit Sub
End If
If e.KeyChar = vbBack Then
Exit Sub
End If
If InStr("0123456789.,", e.KeyChar) = 0 Then
e.KeyChar = ""
End If
End Sub
why does the FileSystemWatcher fire twice? Is there an easy way to fix it? Surely if I update or edit the text file it should only fire once?
this link here http://weblogs.asp.net/ashben/archive/2003/10/14/31773.aspx says
Events being raised twice - An event will be raised twice if an event handler (AddHander FSW.Created, AddressOf FSW_Created) is
explicitly specified. This is because, by default, the public events
automatically call the respective protected methods (OnChanged,
OnCreated, OnDeleted, OnRenamed). To correct this problem, simply
remove the explicit event handler (AddHandler ...).
What does "remove the explicit event handler" mean?
Imports System.IO
Public Class Form2
Private Sub FileSystemWatcher1_Changed(ByVal sender As System.Object, ByVal e As System.IO.FileSystemEventArgs) Handles FileSystemWatcher1.Changed
'this fires twice
MessageBox.Show("test")
End Sub
Private Sub Form2_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
FileSystemWatcher1.Path = "C:\Users\c\Desktop\test\"
FileSystemWatcher1.NotifyFilter = NotifyFilters.LastAccess Or NotifyFilters.LastWrite Or NotifyFilters.FileName Or NotifyFilters.DirectoryName Or NotifyFilters.CreationTime
FileSystemWatcher1.IncludeSubdirectories = False
FileSystemWatcher1.Filter = "text.txt"
End Sub
End Class
Update:
I have come up with 2 solutions. One uses Threads, and the other doesn't. Take your pick :-).
Without threading:
Imports System.IO
Public Class Form1
Private Sub FileSystemWatcher1_Changed(ByVal sender As System.Object, ByVal e As System.IO.FileSystemEventArgs) Handles FileSystemWatcher1.Changed
Dim watcher As System.IO.FileSystemWatcher = sender
watcher.EnableRaisingEvents = False
'Do work here while new events are not being raised.
MessageBox.Show("Test")
watcher.EnableRaisingEvents = True 'Now we can begin watching for new events.
End Sub
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
FileSystemWatcher1.Path = "C:\Users\c\Desktop\test"
FileSystemWatcher1.NotifyFilter = NotifyFilters.LastWrite
FileSystemWatcher1.IncludeSubdirectories = False
FileSystemWatcher1.Filter = "test.txt"
End Sub
Private Sub FileSystemWatcher_OnChanged(ByVal sender As System.Object, ByVal e As System.EventArgs)
End Sub
End Class
This solution (without threading), sets the watcher.EnableRaisingEvents to False. It is after this point where you would normally process whatever files are affected (or changed). It then sets the EnableRaisingEvents back to True after your work is done.
With threading:
Imports System.IO
Public Class Form1
Private Sub FileSystemWatcher1_Changed(ByVal sender As System.Object, ByVal e As System.IO.FileSystemEventArgs) Handles FileSystemWatcher1.Changed
FileSystemWatcher1.EnableRaisingEvents = False
Threading.Thread.Sleep(250)
FileSystemWatcher1.EnableRaisingEvents = True
MessageBox.Show("test")
End Sub
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
FileSystemWatcher1.Path = "C:\Users\c\Desktop\test"
FileSystemWatcher1.NotifyFilter = NotifyFilters.LastWrite
FileSystemWatcher1.IncludeSubdirectories = False
FileSystemWatcher1.Filter = "test.txt"
End Sub
Private Sub FileSystemWatcher_OnChanged(ByVal sender As System.Object, ByVal e As System.EventArgs)
End Sub
End Class
This solution, although a bit hacky, does work. It disables checking for new changes/events for 250ms and then re-enables checking, based on the assumption that you won't been needing to check for a change every 250ms. I have tried almost everything that I could think of to get a real solution for you but this will work in the meantime.
Check e.ChangeType. I imagine you're getting two different notifications. Perhaps LastAccess and LastModified. In which case, that's the expected behavior.
Today i crashed in FileSystemWatcher and found this site. Suggested Thread.Sleep cannot completely eliminate problem. Tested with fast counter-integer. And is blocking UI. Most problematic is startup, it sliped trough at 5s. Then i set FileSystemWatcher1.EnableRaisingEvents = False immediately in TimerWatcherChanged.Tick and never enabled again... But surprisingly counter still catch up-to 4 events! I would like to share my solution, non-blocking, with adjustable Timer. Feedback is welcome.
Imports System.IO
Imports System.Diagnostics
Public Class Form1
Dim fileName As String
Dim Fsw_counter As Integer
WithEvents TimerWatcherChanged As New Windows.Forms.Timer
WithEvents TimerTest As New Windows.Forms.Timer
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
TimerWatcherChanged.Interval = 100
TimerTest.Interval = 100 : TimerTest.Start()
TextBox1.Text = "C:\Downloads\New Text Document.txt"
TextBox1.SelectionStart = TextBox1.Text.Length
WatcherSetup()
End Sub
Sub WatcherSetup()
fileName = TextBox1.Text
FileSystemWatcher1.IncludeSubdirectories = False
FileSystemWatcher1.Path = Path.GetDirectoryName(fileName)
FileSystemWatcher1.Filter = Path.GetFileName(fileName)
FileSystemWatcher1.NotifyFilter = NotifyFilters.LastWrite
FileSystemWatcher1.EnableRaisingEvents = True
End Sub
Private Sub TextBox1_TextChanged(sender As Object, e As EventArgs) Handles TextBox1.TextChanged
WatcherSetup()
End Sub
Private Sub FileSystemWatcher1_Changed(sender As Object, e As FileSystemEventArgs) Handles FileSystemWatcher1.Changed
If TimerWatcherChanged.Enabled = False Then
TimerWatcherChanged.Enabled = True
Fsw_counter += 1
' ***** Your WATCH Code put here... *****
End If
End Sub
Private Sub TimerWatcherChanged_Tick(sender As Object, e As EventArgs) Handles TimerWatcherChanged.Tick
TimerWatcherChanged.Enabled = False
End Sub
Private Sub TimerTest_Tick(ByVal sender As Object, ByVal e As System.EventArgs) Handles TimerTest.Tick
TextBox2.Text = "Changed: " & Fsw_counter
If TimerWatcherChanged.Enabled = True Then
TextBox2.BackColor = Color.Red
Else
TextBox2.BackColor = Color.LawnGreen
End If
End Sub
End Class
I'm looking for a way to detect if the user has been idle for 5 min then do something, and if and when he comes back that thing will stop, for example a timer.
This is what i have tried (but this will only detect if form1 has been inactive / not clicked or anything):
Public Class Form1
Private Sub form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
'You should have already set the interval in the designer...
Timer1.Start()
End Sub
Private Sub form1_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles Me.KeyPress
Timer1.Stop()
Timer1.Start()
End Sub
Private Sub form1_MouseMove(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Me.MouseMove
Timer1.Stop()
Timer1.Start()
End Sub
Private Sub form1_MouseClick(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Me.MouseClick
Timer1.Stop()
Timer1.Start()
End Sub
Private Sub Timer_Tick(ByVal sender As Object, ByVal e As System.EventArgs) Handles Timer1.Tick
MsgBox("Been idle for to long") 'I just have the program exiting, though you could have it do whatever you want.
End Sub
End Class
This is done easiest by implementing the IMessageFilter interface in your main form. It lets you sniff at input messages before they are dispatched. Restart a timer when you see the user operating the mouse or keyboard.
Drop a timer on the main form and set the Interval property to the timeout. Start with 2000 so you can see it work. Then make the code in your main form look like this:
Public Class Form1
Implements IMessageFilter
Public Sub New()
InitializeComponent()
Application.AddMessageFilter(Me)
Timer1.Enabled = True
End Sub
Public Function PreFilterMessage(ByRef m As Message) As Boolean Implements IMessageFilter.PreFilterMessage
'' Retrigger timer on keyboard and mouse messages
If (m.Msg >= &H100 And m.Msg <= &H109) Or (m.Msg >= &H200 And m.Msg <= &H20E) Then
Timer1.Stop()
Timer1.Start()
End If
End Function
Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
Timer1.Stop()
MessageBox.Show("Time is up!")
End Sub
End Class
You may have to add code that disables the timer temporarily if you display any modal dialogs that are not implemented in .NET code.
This might work by setting it to just call the Reset idk i just want it work all over the program idk how to do it, i just created this code :
Public Class test
Dim IdleTimer As String
Dim testsave As String
Dim idle_TimerSet As String = 60 '<---- Here You choose The timer (1 per Sec)
Private Sub test_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
IdleTimer = idle_TimerSet
End Sub
Private Sub Idle_Tick(sender As Object, e As EventArgs) Handles Idle.Tick
If IdleTimer <= 1 Then
MsgBox("[ Idle Screen ]")
Else
IdleTimer = IdleTimer - 1 '<--- The Counter
IdleTracker.Text = IdleTimer
End If
End Sub
Private Sub test_MouseDown(sender As Object, e As MouseEventArgs) Handles Me.MouseDown
Call Reset_Idle() 'This is on the main Form
End Sub
Private Sub test_MouseMove(sender As Object, e As MouseEventArgs) Handles Me.MouseMove
Call Reset_Idle() 'This is on the main Form
End Sub
Public Sub Reset_Idle() '<-- The Reset Action
'Idle.Enabled = False
IdleTimer = idle_TimerSet
'Idle.Enabled = True
End Sub
End Class
A few weeks ago I wrote a wrapper for the ServiceController control to enhance and streamline the base ServiceController. One of the changes I made was to add a monitoring component using the System.Threading.Timer object. On any change of status, an event is raised to the parent class. The actual monitoring works fine, but when the event is handled in the main form, my program abruptly ends - no exceptions, no warning, it just quits. Here's a skeleton version of the control:
Public Class EnhancedServiceController
Inherits ServiceController
Public Event Stopped(ByVal sender As Object, ByVal e As System.EventArgs)
Public Event Started(ByVal sender As Object, ByVal e As System.EventArgs)
Private _LastStatus As System.ServiceProcess.ServiceControllerStatus
Private serviceCheckTimer as System.Threading.Timer
Private serviceCheckTimerDelegate as System.Threading.TimerCallback
...
Private Sub StartMonitor()
MyBase.Refresh()
_LastStatus = MyBase.Status
serviceCheckTimerDelegate = New System.Threading.TimerCallback(AddressOf CheckStatus)
serviceCheckTimer = New System.Threading.Timer(serviceCheckTimerDelegate, Nothing, 0, 60*1000)
End Sub
Private Sub CheckStatus()
MyBase.Refresh()
Dim s As Integer = MyBase.Status
Select Case s
Case ServiceControllerStatus.Stopped
If Not s = _LastStatus Then
RaiseEvent Stopped(Me, New System.EventArgs)
End If
Case ServiceControllerStatus.Running
If Not s = _LastStatus Then
RaiseEvent Started(Me, New System.EventArgs)
End If
End Select
_LastStatus = s
End Sub
End Class
And the form:
Public Class Form1
Private Sub ServiceStarted(ByVal sender As Object, ByVal e As System.EventArgs) Handles ESC.Started
Me.TextBox1.Text = "STARTED"
End Sub
Private Sub ServiceStopped(ByVal sender As Object, ByVal e As System.EventArgs) Handles ESC.Stopped
Me.TextBox1.Text = "STOPPED"
End Sub
End Class
If I had to guess, I'd say that there's some sort of thread problem, but I'm not sure how to handle that in the form. Any ideas?
IF it is a threading issue then you are probably trying to update the UI from a non-UI thread.
So something like this should solve that...
Private Delegate Sub UpdateTextBoxDelegate(byval tText as String)
Private Sub UpdateTextBox(byval tText As String)
If Me.InvokeRequired Then
Me.Invoke(New UpdateTextBoxDelegate(AddressOf UpdateTextBox), tText)
Exit Sub
End If
TextBox1.Text = tText
End Sub
Private Sub ServiceStarted(ByVal sender As Object, ByVal e As System.EventArgs) Handles ESC.Started
UpdateTextBox ("STARTED")
End Sub
Private Sub ServiceStopped(ByVal sender As Object, ByVal e As System.EventArgs) Handles ESC.Stopped
UpdateTextBox("STOPPED")
End Sub