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/*--------------------------------------------------------------------------
*
* You may freely copy, distribute, and reuse the code in this example.
* SHL Systemhouse disclaims any warranty of any kind, expressed or
* implied, as to its fitness for any particular use.
*
*
* Controller
*
* Category Of: EOFDelegate
*
* Conforms To: None
*
* Declared In: EOFDelegateControllerCategory.h
*
*
*------------------------------------------------------------------------*/
#import "EOFDelegateControllerCategory.h"
@implementation EOFDelegate (Controller)
/*--------------------------------------------------------------------------
* EOController Delegate Methods
*
* Note that the insert, delete, and update operations are buffered until an
* -saveToDataSource message is sent to the controller. The delegate receives
* delegate messages for these operations as the insert, delete, and update
* operations are sent to the controller. The delegate receives different
* delegate messages when the buffered operations are actually sent on to the
* data source.
*
* typedef enum {
* EONoDataSourceFailure = 0,
* EOContinueDataSourceFailureResponse,
* EORollbackDataSourceFailureResponse
* } EODataSourceFailureResponse;
*
* These return values allow a controller's delegate to determine what
* action should be taken on a failure. EONoDataSourceFailure means there
* was no failure; EOContinuteDataSourceFailureResponse means that the
* failure should be ignored and the operation should continue;
* EORollbackDataSourceFailureResponse means that the controller should
* roll back the data source. EORollbackDataSourceFailureResponse is only
* useful if the data source conforms to the EORollbackDataSource
* protocol.
*
*------------------------------------------------------------------------*/
- (void)controllerDidChangeSelection:(EOController *)controller
{
// Sent when the selection changes.
[[NXApp delegate] announce:controller selector:_cmd];
}
- (BOOL)controllerWillFetch:(EOController *)controller
{
// Informs the delegate that the controller is about to fetch. If the
// delegate returns no the fetch fails; if the delegate returns YES
// the fetch proceeds.
BOOL result = YES;
[[NXApp delegate] announce:controller selector:_cmd];
if ([[NXApp delegate] wantsAlertPanels] == YES)
{
switch (NXRunAlertPanel ("EOController",
"%s", "YES", "NO", NULL, sel_getName(_cmd)))
{
case NX_ALERTALTERNATE:
result = NO;
break;
case NX_ALERTDEFAULT:
default:
result = YES;
break;
}
}
return result;
}
- (void)controller:(EOController *)controller didFetchObject:object
{
// Informs the delegate that the controller has fetched object.
[[NXApp delegate] announce:controller
selector:_cmd
with:[NSArray arrayWithObject:object]];
}
- (BOOL)controller:(EOController *)controller willInsertObject:object
{
// If the delegate returns NO object is released and not inserted.
BOOL result = YES;
[[NXApp delegate] announce:controller
selector:_cmd
with:[NSArray arrayWithObject:object]];
if ([[NXApp delegate] wantsAlertPanels] == YES)
{
switch (NXRunAlertPanel ("EOController",
"%s", "YES", "NO", NULL, sel_getName(_cmd)))
{
case NX_ALERTALTERNATE:
result = NO;
break;
case NX_ALERTDEFAULT:
default:
result = YES;
break;
}
}
return result;
}
- (void)controller:(EOController *)controller didInsertObject:object
{
// Informs the delegate that the controller has inserted object.
[[NXApp delegate] announce:controller
selector:_cmd
with:[NSArray arrayWithObject:object]];
}
- (BOOL)controller:(EOController *)controller willDeleteObject:object
{
// If the delegate returns NO object is not deleted.
BOOL result = YES;
[[NXApp delegate] announce:controller
selector:_cmd
with:[NSArray arrayWithObject:object]];
if ([[NXApp delegate] wantsAlertPanels] == YES)
{
switch (NXRunAlertPanel ("EOController",
"%s", "YES", "NO", NULL, sel_getName(_cmd)))
{
case NX_ALERTALTERNATE:
result = NO;
break;
case NX_ALERTDEFAULT:
default:
result = YES;
break;
}
}
return result;
}
- (void)controller:(EOController *)controller didDeleteObject:object
{
// Informs the delegate that the controller has deleted object.
[[NXApp delegate] announce:controller
selector:_cmd
with:[NSArray arrayWithObject:object]];
}
- (NSDictionary *)controller:(EOController *)controller
willSave: (NSDictionary *)edits
object:object
{
// Invoked by -saveObjects for each object before
// -takeValuesFromDictionary: is sent to the object. If the delegate
// responds nil -takeValuesFromDictionary: is not sent and the controller
// aborts -saveToObjects. The edits will be ignored and the associations
// will not be notified of any change. If the delegate returns a
// dictionary that dictionary will be sent to the object. This method is
// useful for doing validation prior to data actually being sent to the
// object and will also prevent the UI from refreshing.
id result = edits;
[[NXApp delegate] announce:controller
selector:_cmd
with:[NSArray arrayWithObjects: edits, object, nil]];
if ([[NXApp delegate] wantsAlertPanels] == YES)
{
switch (NXRunAlertPanel ("EOController",
"%s", "YES", "NO", NULL, sel_getName(_cmd)))
{
case NX_ALERTALTERNATE:
result = nil;
break;
case NX_ALERTDEFAULT:
default:
result = edits;
break;
}
}
return result;
}
- (void)controller:(EOController *)controller didSaveToObject:object
{
// Informs the delegate that the controller has saved object.
[[NXApp delegate] announce:controller
selector:_cmd
with:[NSArray arrayWithObject:object]];
}
/*--------------------------------------------------------------------------
* NOTE
*
* The following two methods have been commented out to allow natural
* processing of associated events. See comments below for these methods.
*
- (BOOL)controllerWillDiscardEdits:(EOController *)controller
{
// Sent during the -fetch method before the fetch begins if there are any
// operations that haven't been saved to the objects. Also sent when a
// selection is about to change, causing a detail controller to flush its
// caches. The operation is aborted if this method returns NO. The
// delegate should send -saveToObjects if it wants to preserve the
// changes. If the delegate doesn't implement this method the controller
// opens an alert panel warning the user that edits may be lost.
BOOL result = YES;
[[NXApp delegate] announce:controller selector:_cmd];
if ([[NXApp delegate] wantsAlertPanels] == YES)
{
switch (NXRunAlertPanel ("EOController",
"%s", "YES", "NO", NULL, sel_getName(_cmd)))
{
case NX_ALERTALTERNATE:
result = NO;
break;
case NX_ALERTDEFAULT:
default:
result = YES;
break;
}
}
return result;
}
- (BOOL)controllerWillDiscardUpates:(EOController *)controller
{
// Sent during the -fetch method before the fetch begins if there are any
// operations that haven't been saved to the data source. Also sent
// when a selection is about to change, causing a detail controller to
// flush its caches. The fetch is aborted if this method returns NO.
// The delegate should invoke -saveToDataSource if it wants to preserve the
// changes. If the delegate doesn't implement this method the controller
// opens an alert panel warning the user that updates may be lost.
BOOL result = YES;
[[NXApp delegate] announce:controller selector:_cmd];
if ([[NXApp delegate] wantsAlertPanels] == YES)
{
switch (NXRunAlertPanel ("EOController",
"%s", "YES", "NO", NULL, sel_getName(_cmd)))
{
case NX_ALERTALTERNATE:
result = NO;
break;
case NX_ALERTDEFAULT:
default:
result = YES;
break;
}
}
return result;
}
*------------------------------------------------------------------------*/
- (BOOL)controllerWillSaveToDataSource:(EOController *)controller
{
// These delegate messages are sent as the data source is notified of
// changes to data-bearing objects. If the savesToDataSourceAutomatically
// flag is turned off and -saveToDataSource is invoked then the delegate
// is notified of each buffered operation.
BOOL result = YES;
[[NXApp delegate] announce:controller selector:_cmd];
if ([[NXApp delegate] wantsAlertPanels] == YES)
{
switch (NXRunAlertPanel ("EOController",
"%s", "YES", "NO", NULL, sel_getName(_cmd)))
{
case NX_ALERTALTERNATE:
result = NO;
break;
case NX_ALERTDEFAULT:
default:
result = YES;
break;
}
}
return result;
}
- (void)controllerDidSaveToDataSource:(EOController *)controller
{
// These delegate messages are sent as the data source is notified of
// changes to data-bearing objects. If the savesToDataSourceAutomatically
// flag is turned off and -saveToDataSource is invoked then the delegate
// is notified of each buffered operation.
[[NXApp delegate] announce:controller selector:_cmd];
}
- (BOOL)controller:(EOController *)controller
willInsertObject:object
inDataSource:dataSource
{
BOOL result = YES;
[[NXApp delegate] announce:controller
selector:_cmd
with:[NSArray arrayWithObjects: object, dataSource, nil]];
if ([[NXApp delegate] wantsAlertPanels] == YES)
{
switch (NXRunAlertPanel ("EOController",
"%s", "YES", "NO", NULL, sel_getName(_cmd)))
{
case NX_ALERTALTERNATE:
result = NO;
break;
case NX_ALERTDEFAULT:
default:
result = YES;
break;
}
}
return result;
}
- (EODataSourceFailureResponse)controller:(EOController *)controller
failedToInsertObject:object
inDataSource:dataSource
{
int result = EONoDataSourceFailure;
[[NXApp delegate] announce:controller
selector:_cmd
with:[NSArray arrayWithObjects: object, dataSource, nil]];
if ([[NXApp delegate] wantsAlertPanels] == YES)
{
switch (NXRunAlertPanel ("EOController",
"%s", "No Failure", "Continue", "Rollback", sel_getName(_cmd)))
{
case NX_ALERTOTHER:
result = EORollbackDataSourceFailureResponse;
break;
case NX_ALERTALTERNATE:
result = EOContinueDataSourceFailureResponse;
break;
case NX_ALERTDEFAULT:
default:
result = EONoDataSourceFailure;
break;
}
}
return result;
}
- (void)controller:(EOController *)controller
didInsertObject:object
inDataSource:dataSource
{
[[NXApp delegate] announce:controller
selector:_cmd
with:[NSArray arrayWithObjects: object, dataSource, nil]];
}
- (BOOL)controller:(EOController *)controller
willDeleteObject:object
inDataSource:dataSource
{
BOOL result = YES;
[[NXApp delegate] announce:controller
selector:_cmd
with:[NSArray arrayWithObjects: object, dataSource, nil]];
if ([[NXApp delegate] wantsAlertPanels] == YES)
{
switch (NXRunAlertPanel ("EOController",
"%s", "YES", "NO", NULL, sel_getName(_cmd)))
{
case NX_ALERTALTERNATE:
result = NO;
break;
case NX_ALERTDEFAULT:
default:
result = YES;
break;
}
}
return result;
}
- (EODataSourceFailureResponse)controller:(EOController *)controller
failedToDeleteObject:object
inDataSource:dataSource
{
int result = EONoDataSourceFailure;
[[NXApp delegate] announce:controller
selector:_cmd
with:[NSArray arrayWithObjects: object, dataSource, nil]];
if ([[NXApp delegate] wantsAlertPanels] == YES)
{
switch (NXRunAlertPanel ("EOController",
"%s", "No Failure", "Continue", "Rollback", sel_getName(_cmd)))
{
case NX_ALERTOTHER:
result = EORollbackDataSourceFailureResponse;
break;
case NX_ALERTALTERNATE:
result = EOContinueDataSourceFailureResponse;
break;
case NX_ALERTDEFAULT:
default:
result = EONoDataSourceFailure;
break;
}
}
return result;
}
- (void)controller:(EOController *)controller
didDeleteObject:object
inDataSource:dataSource
{
[[NXApp delegate] announce:controller
selector:_cmd
with:[NSArray arrayWithObjects: object, dataSource, nil]];
}
- (BOOL)controller:(EOController *)controller
willUpdateObject:object
inDataSource:dataSource
{
BOOL result = YES;
[[NXApp delegate] announce:controller
selector:_cmd
with:[NSArray arrayWithObjects: object, dataSource, nil]];
if ([[NXApp delegate] wantsAlertPanels] == YES)
{
switch (NXRunAlertPanel ("EOController",
"%s", "YES", "NO", NULL, sel_getName(_cmd)))
{
case NX_ALERTALTERNATE:
result = NO;
break;
case NX_ALERTDEFAULT:
default:
result = YES;
break;
}
}
return result;
}
- (EODataSourceFailureResponse)controller:(EOController *)controller
failedToUpdateObject:object
inDataSource:dataSource;
{
int result = EONoDataSourceFailure;
[[NXApp delegate] announce:controller
selector:_cmd
with:[NSArray arrayWithObjects: object, dataSource, nil]];
if ([[NXApp delegate] wantsAlertPanels] == YES)
{
switch (NXRunAlertPanel ("EOController",
"%s", "No Failure", "Continue", "Rollback", sel_getName(_cmd)))
{
case NX_ALERTOTHER:
result = EORollbackDataSourceFailureResponse;
break;
case NX_ALERTALTERNATE:
result = EOContinueDataSourceFailureResponse;
break;
case NX_ALERTDEFAULT:
default:
result = EONoDataSourceFailure;
break;
}
}
return result;
}
- (void)controller:(EOController *)controller
didUpdateObject:object
inDataSource:dataSource
{
[[NXApp delegate] announce:controller
selector:_cmd
with:[NSArray arrayWithObjects: object, dataSource, nil]];
}
- (void)controller:(EOController *)controller
willRollbackDataSource:(id <EODataSources>)dataSource
{
[[NXApp delegate] announce:controller
selector:_cmd
with:[NSArray arrayWithObject: dataSource]];
}
- (void)controller:(EOController *)controller
didRollbackDataSource:(id <EODataSources>)dataSource
{
[[NXApp delegate] announce:controller
selector:_cmd
with:[NSArray arrayWithObject: dataSource]];
}
- (BOOL)controllerWillUndo:(EOController *)controller
{
BOOL result = YES;
[[NXApp delegate] announce:controller selector:_cmd];
if ([[NXApp delegate] wantsAlertPanels] == YES)
{
switch (NXRunAlertPanel ("EOController",
"%s", "YES", "NO", NULL, sel_getName(_cmd)))
{
case NX_ALERTALTERNATE:
result = NO;
break;
case NX_ALERTDEFAULT:
default:
result = YES;
break;
}
}
return result;
}
- (BOOL)controllerDidUndo:(EOController *)controller
{
BOOL result = YES;
[[NXApp delegate] announce:controller selector:_cmd];
if ([[NXApp delegate] wantsAlertPanels] == YES)
{
switch (NXRunAlertPanel ("EOController",
"%s", "YES", "NO", NULL, sel_getName(_cmd)))
{
case NX_ALERTALTERNATE:
result = NO;
break;
case NX_ALERTDEFAULT:
default:
result = YES;
break;
}
}
return result;
}
- (void)controller:(EOController *)controller
didChangeDataSource: (id <EODataSources>)dataSource
{
[[NXApp delegate] announce:controller
selector:_cmd
with:[NSArray arrayWithObject: dataSource]];
}
- (void)controller:(EOController *)controller
association: (EOAssociation *)association
didEdit: anObject
key: (NSString *)key
value: aValue
{
[[NXApp delegate] announce:controller
selector:_cmd
with:[NSArray arrayWithObjects:
association, anObject, key, aValue, nil]];
}
- (BOOL)controller:(EOController *)controller willUndoObject:anObject
{
BOOL result = YES;
[[NXApp delegate] announce:controller
selector:_cmd
with:[NSArray arrayWithObject: anObject]];
if ([[NXApp delegate] wantsAlertPanels] == YES)
{
switch (NXRunAlertPanel ("EOController",
"%s", "YES", "NO", NULL, sel_getName(_cmd)))
{
case NX_ALERTALTERNATE:
result = NO;
break;
case NX_ALERTDEFAULT:
default:
result = YES;
break;
}
}
return result;
}
- (void)controller:(EOController *)controller didUndoObject:anObject
{
[[NXApp delegate] announce:controller
selector:_cmd
with:[NSArray arrayWithObject: anObject]];
}
@end
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