运行我的应用时，我收到错误消息，指出方法-pilotDataviewcontollerDidCancel:未实现。
我按照类似问题的说明进行操作并没有成功，我添加了其他正在调用的实现文件
#import <UIKit/UIKit.h>
#import "PilotData.h"
@protocol PilotDataViewControllerDelegate;
@interface PilotDataViewController : UIViewController
@property (weak, nonatomic) IBOutlet UITextField *nameField;
@property (weak, nonatomic) IBOutlet UITextField *phoneField;
@property (weak, nonatomic) IBOutlet UITextField *insuranceField;
@property (weak, nonatomic) IBOutlet UITextField *emailField;
@property (nonatomic, weak) id <PilotDataViewControllerDelegate> delegate;
@property (nonatomic, strong) PilotData *currentPilotData;
- (IBAction)cancel:(id)sender;
- (IBAction)save:(id)sender;
@end
@protocol PilotDataViewControllerDelegate
-(void)pilotDataViewControllerDidSave;
-(void)pilotDataViewControllerDidCancel:(PilotData *)pilotDataToDelete;
@end
#import <UIKit/UIKit.h>
#import "PilotDataViewController.h"
@interface ReleasesTableViewController : UITableViewController
<PilotDataViewControllerDelegate, NSFetchedResultsControllerDelegate>
@property (nonatomic, strong) NSManagedObjectContext *managedObjectContext;
@property (nonatomic, strong) NSFetchedResultsController *fetchedResultsController;
@end
//Releasestableviewcontroller.m
#import "ReleasesTableViewController.h"
#import "PilotData.h"
@interface ReleasesTableViewController ()
@end
@implementation ReleasesTableViewController
@synthesize fetchedResultsController = _fetchedResultsController;
-(void) PilotDataViewControllerDidCancel:(PilotData *)PilotDataToDelete {
NSManagedObjectContext *context = self.managedObjectContext;
[context deleteObject:PilotDataToDelete];
[self dismissViewControllerAnimated:NO completion:nil];}
-(void) pilotDataViewControllerDidSave {
NSError *error = nil;
NSManagedObjectContext *context = self.managedObjectContext;
if (![context save:&error]) {
NSLog(@"Error! %@", error);
}
[self dismissViewControllerAnimated:NO completion:nil];}
-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
if ([[segue identifier] isEqualToString:@"pilotEntry"]) {
//
PilotDataViewController *acvc = (PilotDataViewController *)[segue destinationViewController];
acvc.delegate =self;
PilotData *newPilotData = (PilotData *) [[NSEntityDescription insertNewObjectForEntityForName:@"PilotData" inManagedObjectContext:[self managedObjectContext]];
acvc.currentPilotData = newPilotData;
// }
//
// if ([[segue identifier] isEqualToString:@"showDetail"]) {
// DisplayEditViewController *dvc = (DisplayEditViewController *) [segue destinationViewController];
// NSIndexPath *indexPath = [self.tableView indexPathForSelectedRow];
// Course *selectedCourse = (Course *) [self.fetchedResultsController objectAtIndexPath:indexPath];
// dvc.currentCourse = selectedCourse;
// }
}
- (id)initWithStyle:(UITableViewStyle)style
{
self = [super initWithStyle:style];
if (self) {
// Custom initialization
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
// Uncomment the following line to preserve selection between presentations.
// self.clearsSelectionOnViewWillAppear = NO;
// Uncomment the following line to display an Edit button in the navigation bar for this view controller.
// self.navigationItem.rightBarButtonItem = self.editButtonItem;
NSError *error = nil;
if (![[self fetchedResultsController] performFetch:&error]) {
NSLog(@"Error! %@",error);
abort();
}
}
- (void)viewDidUnload
{
[super viewDidUnload];
// Release any retained subviews of the main view.
// e.g. self.myOutlet = nil;
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
return (interfaceOrientation == UIInterfaceOrientationPortrait);
}
#pragma mark - Table view data source
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
return [[self.fetchedResultsController sections]count];
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
id <NSFetchedResultsSectionInfo> secInfo = [[self.fetchedResultsController sections] objectAtIndex:section];
return [secInfo numberOfObjects];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = @"pilotEntry";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
// Configure the cell...
pilotData *pilotData = [self.fetchedResultsController objectAtIndexPath:indexPath];
cell.textLabel.text = course.title;
return cell;
}
-(NSString *) tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section {
return [[[self.fetchedResultsController sections]objectAtIndex:section]name];
}
/*
// Override to support conditional editing of the table view.
- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath
{
// Return NO if you do not want the specified item to be editable.
return YES;
}
*/
// Override to support editing the table view.
- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath
{
if (editingStyle == UITableViewCellEditingStyleDelete) {
NSManagedObjectContext *context = [self managedObjectContext];
pilotData *pilotDataToDelete = [self.fetchedResultsController objectAtIndexPath:indexPath];
[context deleteObject:pilotDataToDelete];
NSError *error = nil;
if (![context save:&error]) {
NSLog(@"Error! %@",error);
}
}
}
/*
// Override to support rearranging the table view.
- (void)tableView:(UITableView *)tableView moveRowAtIndexPath:(NSIndexPath *)fromIndexPath toIndexPath:(NSIndexPath *)toIndexPath
{
}
*/
/*
// Override to support conditional rearranging of the table view.
- (BOOL)tableView:(UITableView *)tableView canMoveRowAtIndexPath:(NSIndexPath *)indexPath
{
// Return NO if you do not want the item to be re-orderable.
return YES;
}
*/
#pragma mark -
#pragma mark Fetched Results Controller section
-(NSFetchedResultsController *) fetchedResultsController {
if (_fetchedResultsController != nil) {
return _fetchedResultsController;
}
NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
NSEntityDescription *entity = [NSEntityDescription entityForName:@"pilotData"
inManagedObjectContext:[self managedObjectContext]];
[fetchRequest setEntity:entity];
NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"pilotName"
ascending:YES];
NSArray *sortDescriptors = [[NSArray alloc] initWithObjects:sortDescriptor, nil];
[fetchRequest setSortDescriptors:sortDescriptors];
_fetchedResultsController = [[NSFetchedResultsController alloc]initWithFetchRequest:fetchRequest managedObjectContext:self.managedObjectContext sectionNameKeyPath:@"pilotName" cacheName:nil];
_fetchedResultsController.delegate = self;
return _fetchedResultsController;
}
-(void) controllerWillChangeContent:(NSFetchedResultsController *)controller {
[self.tableView beginUpdates];
}
-(void) controllerDidChangeContent:(NSFetchedResultsController *)controller {
[self.tableView endUpdates];
}
-(void)controller:(NSFetchedResultsController *)controller didChangeObject:(id)anObject atIndexPath:(NSIndexPath *)indexPath forChangeType:(NSFetchedResultsChangeType)type newIndexPath:(NSIndexPath *)newIndexPath {
UITableView *tableView = self.tableView;
switch (type) {
case NSFetchedResultsChangeInsert:
[tableView insertRowsAtIndexPaths:[NSArray arrayWithObject:newIndexPath] withRowAnimation:UITableViewRowAnimationFade];
break;
case NSFetchedResultsChangeDelete:
[tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
break;
case NSFetchedResultsChangeUpdate: {
pilotData *changedpilotData = [self.fetchedResultsController objectAtIndexPath:indexPath];
UITableViewCell *cell = [tableView cellForRowAtIndexPath:indexPath];
cell.textLabel.text = changedCourse.title;
}
break;
case NSFetchedResultsChangeMove:
[tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
[tableView insertRowsAtIndexPaths:[NSArray arrayWithObject:newIndexPath] withRowAnimation:UITableViewRowAnimationFade];
break;
}
}
-(void) controller:(NSFetchedResultsController *)controller didChangeSection:(id<NSFetchedResultsSectionInfo>)sectionInfo atIndex:(NSUInteger)sectionIndex forChangeType:(NSFetchedResultsChangeType)type {
switch (type) {
case NSFetchedResultsChangeInsert:
[self.tableView insertSections:[NSIndexSet indexSetWithIndex:sectionIndex] withRowAnimation:UITableViewRowAnimationFade];
break;
case NSFetchedResultsChangeDelete:
[self.tableView deleteSections:[NSIndexSet indexSetWithIndex:sectionIndex] withRowAnimation:UITableViewRowAnimationFade];
break;
}
}
#pragma mark - Table view delegate
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
// Navigation logic may go here. Create and push another view controller.
/*
<#DetailViewController#> *detailViewController = [[<#DetailViewController#> alloc] initWithNibName:@"<#Nib name#>" bundle:nil];
// ...
// Pass the selected object to the new view controller.
[self.navigationController pushViewController:detailViewController animated:YES];
*/
}
@end
答案 0 :(得分：2)
我认为您没有尝试在ReleasesTableViewController
PilotDataViewController * object = [[PilotDataViewController alloc] init];
object.delegate = self;
并且您还必须在ReleasesTableViewController
答案 1 :(得分：1)
ReleasesTableViewController应该从PilotDataViewControllerDelegate协议实现所有必需的方法。请在-(void)pilotDataViewControllerDidCancel:课程中实施ReleasesTableViewController方法。