Instance Method

takeStoredValue:forKey:

Sets the value of the property identified by a given key.

Declaration

- (void)takeStoredValue:(id)value forKey:(NSString *)key;

Discussion

This method is used to initialize the receiver with values from an object store (generally, this storage is ultimately from a database) or to restore a value from a snapshot. The default implementation is similar to the implementation of takeValue:forKey:, but it resolves key with a different method/instance variable search order:

  1. Searches for a private accessor method based on key (a method preceded by an underbar). For example, with a key of “lastName”, takeStoredValue:forKey: looks for a method named _setLastName:.

  2. If a private accessor is not found, searches for an instance variable based on key and sets its value directly. For example, with a key of “lastName”, takeStoredValue:forKey: looks for an instance variable named _lastName or lastName.

  3. If neither a private accessor nor an instance variable is found, takeStoredValue:forKey: searches for a public accessor method based on key. For the key “lastName”, this would be setLastName:.

  4. If key is unknown, takeStoredValue:forKey: calls handleTakeValue:forUnboundKey:.

This different search order allows an object to bypass processing that is performed before setting a value through a public API. However, if you always want to use the search order in takeValue:forKey:, you can implement the class method useStoredAccessor to return NO. And as with valueForKey:, you can prevent direct access of an instance variable with the class method accessInstanceVariablesDirectly.

See Also

Deprecated Methods

+ useStoredAccessor

Returns YES if the stored value methods storedValueForKey: and takeStoredValue:forKey: should use private accessor methods in preference to public accessors.

Deprecated
- handleQueryWithUnboundKey:

Invoked by valueForKey: when it finds no property corresponding to key.

Deprecated
- handleTakeValue:forUnboundKey:

Invoked by takeValue:forKey: when it finds no property binding for key.

Deprecated
- storedValueForKey:

Returns the property identified by a given key.

Deprecated
- takeValuesFromDictionary:

Sets properties of the receiver with values from a given dictionary, using its keys to identify the properties

Deprecated
- takeValue:forKeyPath:

Sets the value for the property identified by keyPath to value.

Deprecated
- takeValue:forKey:

Sets the value for the property identified by key to value.

Deprecated
- unableToSetNilForKey:

Invoked if key is represented by a scalar attribute.

Deprecated
- valuesForKeys:

Returns a dictionary containing as keys the property names in keys, with corresponding values being the corresponding property values.

Deprecated