Description

TNotifiablePersistent extends TPlainInterfacedPersistent by adding a deferred notification and update lock mechanism.

It allows callers to batch multiple state modifications between calls to BeginUpdate and EndUpdate (or BeginLockUpdate and EndLockUpdate), postponing (or disabling) OnChange events until the batch operation completes.

Methods

Name	Description
BeginUpdate	Increments the update counter to defer change notifications during batch modifications.
EndUpdate	Decrements the update counter and triggers Changed if modifications occurred while suspended.
BeginLockUpdate	Increments the lock update counter.
EndLockUpdate	Decrements the lock update counter.
Changed	Triggers the change notification flow or marks the object as modified if updates are suspended.
DoChanged	Protected virtual method that executes the OnChange event handler.

Properties

Name	Type	Scope	Description
UpdateCount	Integer	Protected	Current nest level of BeginUpdate / EndUpdate blocks.
LockUpdateCount	Integer	Protected	Current nest level of BeginLockUpdate / EndLockUpdate blocks.
Modified	Boolean	Protected	Indicates whether changes occurred while UpdateCount > 0.

Events

Name	Type	Description
OnChange	TNotifyEvent	Fired when the object state changes and updates are not suspended.