TICDSSyncTransaction Class Reference
| Inherits from | NSObject |
| Declared in | TICDSSyncTransaction.h |
Overview
The TICDSSyncTransaction class exists to maintain data integrity with regards to applied sync changes.
When the TICoreDataSync framework creates TICDSSynchronizationOperation instances to synchronize changes made to a document, these changes cannot be considered fully applied until the root NSManagedObjectContext of the application has been saved and the applied changes have been written to a persistent store.
Prior to a synchronization process kicking off the TICDSDocumentSyncManager creates an instance of TICDSSyncTransaction. This instance is handed off to the TICDSPreSynchronizationOperation, TICDSSynchronizationOperation, and TICDSPostSynchronizationOperation instances. Just before the background context has been saved (the child context to the document’s context) the TICDSSyncTransaction is “opened”.
Once the TICDSSyncTransaction instance is opened it begins listening to NSManagedObjectContextDidSaveNotification notifications for each of the application’s NSManagedObjectContext instances starting with the document’s context and traversing up the family tree to the root context. As these contexts are saved the TICDSSyncTransaction instance acknowledges that save until it gets a notification from the root context. Once the root context has been saved the TICDSSyncTransaction instance notifies its delegate that it can be closed.
When the close method is called the TICDSSyncTransaction instance migrates the unsaved applied sync changes from its *.unsavedticdsync store to the AppliedSyncChangeSets.ticdsync store and notifies its delegate of success or failure.
Tasks
Other Methods
-
unsavedAppliedSyncChangesFileURLThe URL to the unsaved applied sync change sets file for this sync transaction.
property -
appliedSyncChangesFileURLThe path to the applied sync change sets file.
property -
errorAny errors that occur while this transaction is open will be saved to this property.
property -
delegateThe delegate that will receive
propertyTICDSSyncTransactionDelegatemessages. -
stateThe current state of the sync transaction. Before the transaction has been opened its state will be TICDSSyncTransactionStateNotYetOpen. Once it has been opened its state will be TICDSSyncTransactionStateOpen. After the transaction has been closed successfully the state will be TICDSSyncTransactionStateClosed. If an attempt to close the transaction has been made and it fails the state will be TICDSSyncTransactionStateUnableToClose. The error property will most likely be non-nil as well.
property
Designated Initializer
-
– initWithDocumentManagedObjectContext:unsavedAppliedSyncChangesDirectoryPath:Initialize a sync transaction with the document’s managed object context and the path to the directory where this transaction should write its unsaved applied sync change sets file.
-
– openImmediately prior to a background sync
NSManagedObjectContextbeing saved by aTICDSSynchronizationOperation, that operation’sTICDSSyncTransactionshould be “opened” by calling its open method. -
– closeOnce the
TICDSSyncTransactionindicates via its delegate that it can be closed this method can be called to close the transaction.
Properties
appliedSyncChangesFileURL
The path to the applied sync change sets file.
@property NSURL *appliedSyncChangesFileURLDeclared In
TICDSSyncTransaction.hdelegate
The delegate that will receive TICDSSyncTransactionDelegate messages.
@property (weak) id<TICDSSyncTransactionDelegate> delegateDeclared In
TICDSSyncTransaction.herror
Any errors that occur while this transaction is open will be saved to this property.
@property NSError *errorDeclared In
TICDSSyncTransaction.hstate
The current state of the sync transaction. Before the transaction has been opened its state will be TICDSSyncTransactionStateNotYetOpen. Once it has been opened its state will be TICDSSyncTransactionStateOpen. After the transaction has been closed successfully the state will be TICDSSyncTransactionStateClosed. If an attempt to close the transaction has been made and it fails the state will be TICDSSyncTransactionStateUnableToClose. The error property will most likely be non-nil as well.
@property TICDSSyncTransactionState stateDeclared In
TICDSSyncTransaction.hInstance Methods
close
Once the TICDSSyncTransaction indicates via its delegate that it can be closed this method can be called to close the transaction.
- (void)closeDeclared In
TICDSSyncTransaction.hinitWithDocumentManagedObjectContext:unsavedAppliedSyncChangesDirectoryPath:
Initialize a sync transaction with the document’s managed object context and the path to the directory where this transaction should write its unsaved applied sync change sets file.
- (id)initWithDocumentManagedObjectContext:(NSManagedObjectContext *)managedObjectContext unsavedAppliedSyncChangesDirectoryPath:(NSString *)unsavedAppliedSyncChangesDirectoryPathParameters
- managedObjectContext
The document’s managed object context, the one that was registered with the document sync manager.
- unsavedAppliedSyncChangesDirectoryPath
The path to the directory where the unsaved applied sync change set files will be placed. This directory location should exist before being given to the sync transaction.
Return Value
An initialized synchronization operation.
Declared In
TICDSSyncTransaction.hopen
Immediately prior to a background sync NSManagedObjectContext being saved by a TICDSSynchronizationOperation, that operation’s TICDSSyncTransaction should be “opened” by calling its open method.
- (void)openDeclared In
TICDSSyncTransaction.h