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How to disable the numericupdown event firing?Hello,
A probably dumb question... does anyone know hot to avoid that if one keep the mouse pressed on an arrow of the numericUpDown it continues to fire events (it uses evidently a timer) ? I want 1 event for each click, and no timer activation. I have tried using disable within the handler but does not work. Any idea? tommaso I assume you do not want the SelectedIndexChanged event to only fire
once? Why not create a Boolean property in the Form's class, and manipulate it with the MouseDown and MouseUp events to indicate the state of the mousebutton. Then the SelectedIndexChanged event can check this property and if set, exit. hi!
thanks for the reply. Checking mouse event can't do it, IMHO, as the mouse can ble clicked out of the arrows, unless one knows how to detect that (?). (I am not sure what you mean by "SelectedIndexChanged ": I am using VB 2005 and I do not have this event for the "NumericUpDown". Perhaps you meant another control...). Any other ideas? -tommaso I was talking aout the MouseUp and MouseDown events for the numeric
updown control, which fire ONLY when you click on the numeric updown controls buttons. I have used the NUD control and it most certainly has a
SelectedIndexChanged event, which I use to change the value displayed in a related textbox. If you are not using any of the NUD's events, I don't see what your problem is. mmm, well there must be some misundertunding here.
I have just tried and the MouseDown and MouseUp events are raised even if you do not click on the arrows of the NumericUpDown. Further I am not able to find the "SelectedIndexChanged" for the NumericUpDown. Could you provide a pointer to the documentation where it is dealt with? At this point I am a little bit confused. I still think we are talking about different things (perhaps you talk about a ComboBox ??)... tommaso Sorry, my bad. Not SelectedIndexChanged, ValueChanged.
ms-help://MS.VSCC.v80/MS.MSDN.v80/MS.NETDEVFX.v20.en/CPref17/html/E_System_Windows_Forms_NumericUpDown_ValueChanged.htm And you are right, to a degree. The MouseDown and MoustUp event do fire if the mouse is simply somewhere over the control and the mouse button is clicked, not when you click on one of the control's up or down buttons. There may be some way to use them with the ValueChanged event or some other event to accomplish your desired result. Yes. Let me explain further my problem, which actually I believe is a
BUG of the numericUpDown control which was already present in version 2003, and the VS team does not *seem* to have done anything about it. ANYTIME you place any code under the ValueChanged event which take a little while to execute (I do not mean a very long process [which could justify for instance a new thread], but something within tens of a second), if you keep the mouse clicked on one arrow you systematically, that is ALWAYS get the following error: ---------------------------- System.NullReferenceException was unhandled Message="Object reference not set to an instance of an object." Source="System.Windows.Forms" StackTrace: at System.Windows.Forms.UpDownBase.UpDownButtons.TimerHandler(Object source, EventArgs args) at System.Windows.Forms.Timer.OnTick(EventArgs e) at System.Windows.Forms.Timer.TimerNativeWindow.WndProc(Message& m) at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam) at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg) at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(Int32 dwComponentID, Int32 reason, Int32 pvLoopData) at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context) at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context) at System.Windows.Forms.Application.Run(ApplicationContext context) at Microsoft.VisualBasic.ApplicationServices.WindowsFormsApplicationBase.OnRun() at Microsoft.VisualBasic.ApplicationServices.WindowsFormsApplicationBase.DoApplicationModel() at Microsoft.VisualBasic.ApplicationServices.WindowsFormsApplicationBase.Run(String[] commandLine) at Trial.My.MyApplication.Main(String[] Args) in 17d14f5c-a337-4978-8281-53493378c1071.vb:line 81 ------------------ and there seems anything one can do about it. That's why I wished to disable the associated timer. Because it causes an exception I cannot do anything about. If anyone has suggestion to solve this annoying problem (and I do hope someone of the VS team is listening) I would like to know. tommaso Hmm, you know, the app I wrote that uses the NUD control does some
calculations in the ValueChanged event, and I can hold down either the up or the down button, and I have never (so far) gotten the exception you get. The calculations are not intense, but are not trivial either. Maybe I will test it and see if I can re-create your problem. It doesn't take much to reproduce the bug. It is crucial (to get the
exception) that the called routine allows events (DOEVENTS). I get systematically this exception when drawing something within the ValueChanged event. Here is the BUG demo code. Just create a form with a NumericUpDown and paste the code. Run the program. Click on the UP arrow and keep pressed. You will get the exception very soon. I don't go beyond 11. '--------------------------------begin code Public Class Form1 Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load Me.NumericUpDown1.Maximum = Decimal.MaxValue End Sub Private Sub NumericUpDown1_ValueChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles NumericUpDown1.ValueChanged Me.SomeTaskWithEvents() End Sub Sub SomeTaskWithEvents() System.Threading.Thread.Sleep(10) Application.DoEvents() End Sub End Class '--------------------------------end code - Details System.NullReferenceException was unhandled Message="Object reference not set to an instance of an object." Source="System.Windows.Forms" StackTrace: at System.Windows.Forms.UpDownBase.UpDownButtons.TimerHandler(Object source, EventArgs args) at System.Windows.Forms.Timer.OnTick(EventArgs e) at System.Windows.Forms.Timer.TimerNativeWindow.WndProc(Message& m) at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam) at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg) at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(Int32 dwComponentID, Int32 reason, Int32 pvLoopData) at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context) at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context) at System.Windows.Forms.Application.DoEvents() at BUGNUD.Form1.SomeTaskWithEvents() in C:\Documents and Settings\User\Documenti\Visual Studio 2005\Projects\BUGNUD\BUGNUD\Form1.vb:line 13 at BUGNUD.Form1.NumericUpDown1_ValueChanged(Object sender, EventArgs e) in C:\Documents and Settings\User\Documenti\Visual Studio 2005\Projects\BUGNUD\BUGNUD\Form1.vb:line 8 at System.Windows.Forms.NumericUpDown.OnValueChanged(EventArgs e) ..... In the mouse down event, use the "Remove Handler" to remove the ValueChanged
Event handler then in the MouseUp event, use the Add Handler to restore event handling in the Value Changed Event. This should work. -- Show quoteHide quoteDennis in Houston "tommaso.gasta***@uniroma1.it" wrote: > It doesn't take much to reproduce the bug. It is crucial (to get the > exception) that > the called routine allows events (DOEVENTS). I get systematically this > exception > when drawing something within the ValueChanged event. > > Here is the BUG demo code. Just create a form with a NumericUpDown and > paste the code. > Run the program. Click on the UP arrow and keep pressed. You will get > the exception very soon. > I don't go beyond 11. > > '--------------------------------begin code > > Public Class Form1 > > Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As > System.EventArgs) Handles MyBase.Load > Me.NumericUpDown1.Maximum = Decimal.MaxValue > End Sub > > Private Sub NumericUpDown1_ValueChanged(ByVal sender As > System.Object, ByVal e As System.EventArgs) Handles > NumericUpDown1.ValueChanged > Me.SomeTaskWithEvents() > End Sub > > Sub SomeTaskWithEvents() > System.Threading.Thread.Sleep(10) > Application.DoEvents() > End Sub > > End Class > > '--------------------------------end code > > > > > - Details > > System.NullReferenceException was unhandled > Message="Object reference not set to an instance of an object." > Source="System.Windows.Forms" > StackTrace: > at > System.Windows.Forms.UpDownBase.UpDownButtons.TimerHandler(Object > source, EventArgs args) > at System.Windows.Forms.Timer.OnTick(EventArgs e) > at System.Windows.Forms.Timer.TimerNativeWindow.WndProc(Message& > m) > at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr > hWnd, Int32 msg, IntPtr wparam, IntPtr lparam) > at > System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg) > at > System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(Int32 > dwComponentID, Int32 reason, Int32 pvLoopData) > at > System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 > reason, ApplicationContext context) > at > System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 > reason, ApplicationContext context) > at System.Windows.Forms.Application.DoEvents() > at BUGNUD.Form1.SomeTaskWithEvents() in C:\Documents and > Settings\User\Documenti\Visual Studio > 2005\Projects\BUGNUD\BUGNUD\Form1.vb:line 13 > at BUGNUD.Form1.NumericUpDown1_ValueChanged(Object sender, > EventArgs e) in C:\Documents and Settings\User\Documenti\Visual Studio > 2005\Projects\BUGNUD\BUGNUD\Form1.vb:line 8 > at System.Windows.Forms.NumericUpDown.OnValueChanged(EventArgs > e) > ..... > > hi Dennis,
MouseUp/Down cannot be used to place semaphores or detach handlers as they are fired even when the mouse is clicked on an area of the NUD different from arrows. Further, the ValueChanged is executed under a handles clause and cannot be removed that way,... Could you actually show your suggestion applied to the Bug code? tommaso MouseUp/Down events CAN be used to remove/add handlers. The following works
except that the ValueChanged event is fired ONCE before the mousedown event is fired when the mouse button is held down. Private Sub NumericUpDown1_ValueChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles NumericUpDown1.ValueChanged 'Will fire one time when the mouse is pressed and held then not fire again until the function is called from the MouseUp event. End Sub Private Sub NumericUpDown1_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles NumericUpDown1.MouseDown RemoveHandler NumericUpDown1.ValueChanged, AddressOf NumericUpDown1_ValueChanged End Sub Private Sub NumericUpDown1_MouseUp(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles NumericUpDown1.MouseUp AddHandler NumericUpDown1.ValueChanged, AddressOf NumericUpDown1_ValueChanged Dim e1 As New System.EventArgs 'NumericUpDown1_ValueChanged(sender, e1) End Sub -- Show quoteHide quoteDennis in Houston "tommaso.gasta***@uniroma1.it" wrote: > hi Dennis, > > MouseUp/Down cannot be used to place semaphores or detach handlers as > they are fired even when the mouse is clicked on an area of the NUD > different from arrows. > > Further, the ValueChanged is executed under a handles clause and cannot > be removed that way,... > > Could you actually show your suggestion applied to the Bug code? > > tommaso > > Good! You are right.
You are almost there. There seems to be a last problem. If one clicks on UpArrow and release the mouse and repeat this process starting, for instance, from 1, the ValueChanged events is fired only for the odd numbers. That is in a sequence of clicks only half of them rise the ValueChanged event. But one would like to get the event for each click... Any idea? tommaso mmm, I am afraid that this isn't the right approach. There seems to be
no way to make it work right. Perhaps another approach could be working by reflection and disabling the internal timer. But, It would probably be easier to create a custom NUD! Such a small control is so defective! I still do not understand how come takes so long (years) to fix it ! -t Here is a stupid workaround which seems to work.
I include a complete demo. Requires a NUD and a CheckBox. Whem the CheckBox is not checked the program show the NUD "out of sync" (is that a good name?) BUG, if checked implements the dumb workaround to stop continuous event firing (which causes bug). If you have more suggestions, please let me know. And let's hope that they fix soon the NUD this is the kind of things that make Infragistic (and similar business) happy, I guess ! Public Class Form1 Private DisableFiring As Boolean Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load Me.Text = "NUD BUG Demo" Me.CheckBox1.Text = "Disable continuous firing" Me.NumericUpDown1.Maximum = Decimal.MaxValue End Sub Private Sub NumericUpDown1_ValueChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles NumericUpDown1.ValueChanged If DisableFiring Then Me.NumericUpDown1.Enabled = False Me.SomeTaskWithEvents() If DisableFiring Then NumericUpDown1.Enabled = True End Sub Sub SomeTaskWithEvents() System.Threading.Thread.Sleep(10) Me.Text = "Value " & Me.NumericUpDown1.Value Application.DoEvents() End Sub Private Sub CheckBox1_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox1.CheckedChanged Me.DisableFiring = Me.CheckBox1.Checked End Sub End Class Yes, it's too bad they don't fix the ValueChanged event on the NumericUpDown
control. It should fire the ValueChanged event AFTER the Click event which is fired after the MouseUp event OR have a BeforeValueChange event with a cancel option. Many of Ms controls are like this. I don't think they put much thought into their controls...third party controls are much better normally. -- Show quoteHide quoteDennis in Houston "tommaso.gasta***@uniroma1.it" wrote: > Here is a stupid workaround which seems to work. > > I include a complete demo. Requires a NUD and a CheckBox. Whem the > CheckBox is not checked > the program show the NUD "out of sync" (is that a good name?) BUG, if > checked implements the dumb > workaround to stop continuous event firing (which causes bug). > > If you have more suggestions, please let me know. And let's hope that > they fix soon the NUD > this is the kind of things that make Infragistic (and similar business) > happy, I guess ! > > > Public Class Form1 > > Private DisableFiring As Boolean > > Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As > System.EventArgs) Handles MyBase.Load > Me.Text = "NUD BUG Demo" > Me.CheckBox1.Text = "Disable continuous firing" > Me.NumericUpDown1.Maximum = Decimal.MaxValue > End Sub > > Private Sub NumericUpDown1_ValueChanged(ByVal sender As > System.Object, ByVal e As System.EventArgs) Handles > NumericUpDown1.ValueChanged > If DisableFiring Then Me.NumericUpDown1.Enabled = False > Me.SomeTaskWithEvents() > If DisableFiring Then NumericUpDown1.Enabled = True > End Sub > > Sub SomeTaskWithEvents() > System.Threading.Thread.Sleep(10) > Me.Text = "Value " & Me.NumericUpDown1.Value > Application.DoEvents() > End Sub > > Private Sub CheckBox1_CheckedChanged(ByVal sender As System.Object, > ByVal e As System.EventArgs) Handles CheckBox1.CheckedChanged > Me.DisableFiring = Me.CheckBox1.Checked > End Sub > > End Class > > 
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