InvalidOperationException when closing the Window

State See Verified Answer
Replies 5 replies
Subscribers 6 subscribers
Views 1177263 views
Users 0 members are here

UltraGrid

740

N posted over 15 years ago

Hi there,

I have a child form which pop up from a MdiParent Form. In this Child form I have added some components including BindingSource, Ultra Labels, Ultra Textboxes,Ultra Combos, Ultra Validators etc. Also this form inhertis some features of Wizard from another base class which has functionalites for "Next" and "Previous" buttons. When I go to Finish tab and press the Finish button or if I close it from the close button in the window, it gives the following Error message:

InvalidOperationException : "Databinding cannot occur unless a BindingContext or BindingContextControl has been specified."

   at Infragistics.Win.BindableValueList.SetDataBinding(Object dataSource, String dataMember)
   at Infragistics.Win.BindableValueList.OnDataSourceDisposed(Object sender, EventArgs e)
   at System.EventHandler.Invoke(Object sender, EventArgs e)
   at System.ComponentModel.Component.Dispose(Boolean disposing)
   at System.Windows.Forms.BindingSource.Dispose(Boolean disposing)
   at System.ComponentModel.Component.Dispose()
   at System.ComponentModel.Container.Dispose(Boolean disposing)
   at System.ComponentModel.Container.Dispose()

Position of coding which the error occur marked in red:

protected virtual void Dispose(bool disposing) {

if (disposing) {

lock(this) {

if (site != null && site.Container != null) {

site.Container.Remove(this);

}

if (events != null) {

EventHandler handler = (EventHandler)events[EventDisposed];

if (handler != null) handler(this, EventArgs.Empty);

}

I would like to know whats the cause of this exception if anyone came across with the same issue.

Need help urgently!

Regards,

Parents

No Data

Reply

469350

Offline Mike Saltzman posted over 15 years ago

Hi,
I'm not sure exactly what this code it. But it looks like it's the Dispose method of your form. Is that right?
If that's the case, then it appears that your form's Dispose method is firing events - which probably isn't a good idea. Did you add that code to the Dispose method? If so, why are you attempting to fire events when the form is being disposed?
If that code was added automatically, then I'm not sure where it came from, but it could be a bug.
Cancel
Reply

Cancel

Children

740

N posted over 15 years ago in reply to Mike Saltzman

Hi Mike,

Thanks for your reply.
The code which has Dispose method is at System.ComponentModel.Component and it is auto generated.
protected virtual void Dispose(bool disposing) {
if (disposing) { lock(this) {if (site != null && site.Container != null) {site.Container.Remove(this); }if (events != null) {EventHandler handler = (EventHandler)events[EventDisposed];if (handler != null) handler(this, EventArgs.Empty); }}}
}

And my class has the following Dispose method.
protected override void Dispose(bool disposing)
{if (disposing && (components != null)) {components.Dispose();}
base.Dispose(disposing);
}

I think from the components.Dispose() method it goes to the Component class Dispose() method. I think when disposing, some events are not being released. And I just added the following code to dispose the components which has events. But when the bindingsource.dispose() method fires, it goes to that same exception.
private void AddUser_FormClosed(object sender, FormClosedEventArgs e)
{this.ultraLabel1.Dispose();this.ultraLabel2.Dispose(); this.txtText1.Dispose();this.uDateTimeEditor1.Dispose();this.ultraValidator1.Dispose();
this.genderBindingSource.Dispose(); //HERE GETS THE ERROR!!!!
}

How can I solve this exception? Help please!!

nw
Cancel
Reply

Cancel