DADelta
Overview
The DADelta class is used internally to maintain a list of inserted, deleted and updated rows in a DADataTable until they are sent to the server and applied to the back-end database. Each contained change is represented by a DADeltaChange instance.
Location
- Reference: DADelta.h
- Namespace: DataAbstract
- Ancestry: NSObject | DADelta
addChange:
Appends given change to delta's change list.
- (void) addChange:(DADeltaChange *)change
Parameters:
- change: Change we want to append.
changes
Provides access to the array of DADeltaChange objects.
@property (readonly) NSArray *changes
deltaWithTable:
Creates and initializes a new DADelta' object with the changes from the given table.
+ (id) deltaWithTable:(DADataTable *)ownerTable
Parameters:
- ownerTable: Reference to the DADataTable for which the delta will be created.
errorMessages
Returns all error messages that were returned when trying to apply changes to the server.
@property (readonly) NSString *errorMessages
errors
Returns an array of all failed DADeltaChanges.
@property (readonly) NSArray *errors
hasErrors
Returns YES if one or more changes have failed to be applied on the server, NO if all changes were applied successfully.
@property (readonly) BOOL hasErrors
initWithTable:
- (InstanceType) initWithTable:(DADataTable *)ownerTable
Parameters:
- ownerTable:
lockRows
This method is used internally by DARemoteDataAdapter to lock changed rows and prevent them from future changes. Locking is important in case of asynchronous updating data. We need to be sure that pending changes will not be modified at the client side while they trying to apply at the server
- (void) lockRows
name
Delta name (which equals to the name of the data table)
@property (readonly) NSString *name
table retain
Returns reference to DADataTable to which this delta belongs.
@property (retain) DADataTable *table
unlockRows
This method is used internally by DARemoteDataAdapter to unlock changed rows and allow their future changes. Unlock is called after the server returns a response if the request was successful or unsuccessful
- (void) unlockRows
updateWithDelta:
- (void) updateWithDelta:(DADelta *)delta
Parameters:
- delta:
changes
Provides access to the array of DADeltaChange objects.
@property (readonly) NSArray *changes
errorMessages
Returns all error messages that were returned when trying to apply changes to the server.
@property (readonly) NSString *errorMessages
errors
Returns an array of all failed DADeltaChanges.
@property (readonly) NSArray *errors
hasErrors
Returns YES if one or more changes have failed to be applied on the server, NO if all changes were applied successfully.
@property (readonly) BOOL hasErrors
name
Delta name (which equals to the name of the data table)
@property (readonly) NSString *name
table retain
Returns reference to DADataTable to which this delta belongs.
@property (retain) DADataTable *table
deltaWithTable:
Creates and initializes a new DADelta' object with the changes from the given table.
+ (id) deltaWithTable:(DADataTable *)ownerTable
Parameters:
- ownerTable: Reference to the DADataTable for which the delta will be created.
addChange:
Appends given change to delta's change list.
- (void) addChange:(DADeltaChange *)change
Parameters:
- change: Change we want to append.
initWithTable:
- (InstanceType) initWithTable:(DADataTable *)ownerTable
Parameters:
- ownerTable:
lockRows
This method is used internally by DARemoteDataAdapter to lock changed rows and prevent them from future changes. Locking is important in case of asynchronous updating data. We need to be sure that pending changes will not be modified at the client side while they trying to apply at the server
- (void) lockRows
unlockRows
This method is used internally by DARemoteDataAdapter to unlock changed rows and allow their future changes. Unlock is called after the server returns a response if the request was successful or unsuccessful
- (void) unlockRows
updateWithDelta:
- (void) updateWithDelta:(DADelta *)delta
Parameters:
- delta:
- DADataTable class
- DADeltaChange class