SchedulerStorageBase.ResourceCollectionAutoReloading Event

Occurs when the data source which contains resources is modified and the automatic reloading of resources is enabled.

Namespace: DevExpress.XtraScheduler

Assembly: DevExpress.XtraScheduler.v20.1.Core.dll

Declaration

public event CancelListChangedEventHandler ResourceCollectionAutoReloading
Public Event ResourceCollectionAutoReloading As CancelListChangedEventHandler

Event Data

The ResourceCollectionAutoReloading event's data class is CancelListChangedEventArgs. The following properties provide information specific to this event:

Property Description
Cancel Gets or sets whether the operation performed on the processed event should be canceled.
ListChangedType Gets the type of change. Inherited from ListChangedEventArgs.
NewIndex Gets the index of the item affected by the change. Inherited from ListChangedEventArgs.
OldIndex Gets the old index of an item that has been moved. Inherited from ListChangedEventArgs.
PropertyDescriptor Gets the PropertyDescriptor that was added, changed, or deleted. Inherited from ListChangedEventArgs.

Remarks

You can use the DataMember and DataSource properties of the ResourceStorageBase object to bind the SchedulerStorageBase object to the data source which contains resources for appointments. In this case, resources will be automatically obtained from the specified data source.

When the PersistentObjectStorage<T>.AutoReload property of the ResourceStorageBase object is set to true, the data is automatically reloaded. In this case, the SchedulerStorage object reloads data from the data source each time an item in the data source is modified, added, moved or removed, a column is added, modified or deleted or multiple changes are made to the data source. The SchedulerStorageBase.ResourceCollectionAutoReloading event allows you to prevent data from being reloaded in specific cases. Use the event's ListChangedType parameter to determine the reason for the data source changes. To prevent data from being reloaded in a specific case set the Cancel parameter to true. Otherwise, the scheduler storage object will always reload data from the data source immediately after the event handler has completed.

The ResourceCollectionAutoReloading event doesn't fire in the following cases:

Examples

In the following example the SchedulerDataStorage.AppointmentCollectionAutoReloading and SchedulerDataStorage.ResourceCollectionAutoReloading events are handled to prevent appointments and appointment resources from being reloaded from a data source in the following cases:

  • When a data source item (row) is being moved to a new position.
  • When a column (field) is added, modified or deleted in the data source.
 using System.ComponentModel;
 using DevExpress.XtraScheduler;
 // ...

 // Subscribe to the event which controls data reloading 
 // for the data source which contains appointments.
 schedulerControl.DataStorage.AppointmentCollectionAutoReloading += 
    new CancelListChangedEventHandler(OnCollectionAutoReloading);

 // Subscribe to the event which controls data reloading 
 // for the data source which contains appointment resources.
 schedulerControl.DataStorage.ResourceCollectionAutoReloading += 
    new CancelListChangedEventHandler(OnCollectionAutoReloading);


 private void OnCollectionAutoReloading(object sender, 
    CancelListChangedEventArgs e) {
    // Prevent data reloading when the data source is modified in specific cases.
    if(e.ListChangedType == ListChangedType.ItemMoved || e.ListChangedType == 
        ListChangedType.PropertyDescriptorAdded || 
        e.ListChangedType == ListChangedType.PropertyDescriptorChanged || 
        e.ListChangedType == ListChangedType.PropertyDescriptorDeleted)
       e.Cancel = true;
 }
See Also