TRecall¶

Helper class for storing published properties.

Declaration¶

Source position: classesh.inc line 866

type

  TRecall = class(TObject)
  public
    constructor Create;
    destructor Destroy;
    procedure Store;
    procedure Forget;
    property Reference: TPersistent; {r}
  end;

Inheritance¶

Description¶

TRecall is a helper class used to copy published properties of a class (the reference object) in another class (the storage object). The reference object and storage object must be assignable to each other.

The TRecall can be used to store the state of a persistent class, and restore it at a later time.

When a TRecall object is created, it gets passed a reference instance and a storage instance. It immediately stores the properties of the reference object in the storage object.

The Store method can be called throughout the lifetime of the reference object to update the stored properties.

When the TRecall instance is destroyed then the properties are copied from the storage object to the reference object. The storage object is freed automatically.

If the properties should not be copied back from the storage to the reference object, the Forget can be called.

Properties¶

Member	Visibility	Description
Reference read only	public	The reference object.

See all Properties

Methods¶

Member	Visibility	Description
Create	public	Creates a new instance of TRecall.
Destroy	public	Copies the stored properties to the reference object and destroys the TRecall instance.
Forget	public	Clear the reference property.
Store	public	Assigns the reference instance to the storage instance.

See all Methods

Name	Description
TRecall.Create	Creates a new instance of TRecall.
TRecall.Destroy	Copies the stored properties to the reference object and destroys the TRecall instance.
TRecall.Forget	Clear the reference property.
TRecall.Store	Assigns the reference instance to the storage instance.
TPersistent.Assign	Assign the contents of one class to another.