using DevExpress.ExpressApp;
using DevExpress.Persistent.BaseImpl;
using DevExpress.ExpressApp.SystemModule;
public class LimitTaskAmountController : ViewController {
private NewObjectViewController controller;
protected override void OnActivated() {
base.OnActivated();
controller = Frame.GetController<NewObjectViewController>();
if (controller != null) {
controller.ObjectCreating = controller_ObjectCreating;
}
}
void controller_ObjectCreating(object sender, ObjectCreatingEventArgs e) {
if ((e.ObjectType == typeof(Task)) &&
(e.ObjectSpace.GetObjectsCount(typeof(Task), null) >= 3)) {
e.Cancel = true;
throw new UserFriendlyException(
"Cannot create a task. Maximum allowed task count exceeded.");
}
}
protected override void OnDeactivated() {
if (controller != null) {
controller.ObjectCreating -= controller_ObjectCreating;
}
base.OnDeactivated();
}
}
Imports DevExpress.ExpressApp
Imports DevExpress.Persistent.BaseImpl
Imports DevExpress.ExpressApp.SystemModule
Public Class LimitTaskAmountController
Inherits ViewController
Private controller As NewObjectViewController
Protected Overrides Sub OnActivated()
MyBase.OnActivated()
controller = Frame.GetController(Of NewObjectViewController)()
If controller IsNot Nothing Then
AddHandler controller.ObjectCreating, AddressOf controller_ObjectCreating
End If
End Sub
Private Sub controller_ObjectCreating(ByVal sender As Object, ByVal e As ObjectCreatingEventArgs)
If (e.ObjectType Is GetType(Task)) AndAlso (e.ObjectSpace.GetObjectsCount(GetType(Task), Nothing) >= 3) Then
e.Cancel = True
Throw New UserFriendlyException("Cannot create a task. Maximum allowed task count exceeded.")
End If
End Sub
Protected Overrides Sub OnDeactivated()
If controller IsNot Nothing Then
RemoveHandler controller.ObjectCreating, AddressOf controller_ObjectCreating
End If
MyBase.OnDeactivated()
End Sub
End Class
