View Event Handlers

Views support the same DataEventHandler pattern as tables, since both inherit from Common. Event handlers allow you to subscribe to lifecycle events on a view without modifying its source code.

Since views are typically used for read operations, the most commonly used events are related to validation and post-load processing. However, the full set of data events is available if the view supports write operations.

Registering an Event Handler

class SAMOCustTransViewEventHandlers
{
    [DataEventHandler(tableStr(SAMOCustTransView), DataEventType::PostLoad)]
    public static void SAMOCustTransView_onPostLoad(Common _sender, DataEventArgs _e)
    {
        SAMOCustTransView view = _sender as SAMOCustTransView;
        // Post-load enrichment
    }
}

Common View Events

Event	Use Case
PostLoad	Populate computed/display fields after the record is loaded from the view.
ValidatedWrite	Add validation when the view supports insert/update (e.g., updatable views).
ValidatedField	Field-level validation for form-bound view fields.
InitializedRecord	Set default values when a new record is created through the view.

Example: Validating a View Record

class SAMOCustTransViewEventHandlers
{
    [DataEventHandler(tableStr(SAMOCustTransView), DataEventType::ValidatedWrite)]
    public static void SAMOCustTransView_onValidatedWrite(Common _sender, DataEventArgs _e)
    {
        ValidateEventArgs validateArgs = _e as ValidateEventArgs;
        SAMOCustTransView view = _sender as SAMOCustTransView;

        if (validateArgs.parmValidateResult()
            && view.AmountMST == 0)
        {
            validateArgs.parmValidateResult(
                checkFailed("@SAMO:AmountCannotBeZero"));
        }
    }
}

Refer to the Table Event Handlers page for the complete DataEventType reference — the same events and delegate signatures apply to views.