尝试覆盖Objective-C(iPhone)中的方法时出现问题 [英] Problems trying to override methods in Objective-C (iPhone)
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问题描述
这是我的问题，我有一个继承UITableViewController类的类X和一个继承X类的类Y，当我尝试覆盖Y类中的方法时，将调用X类中的方法...并且我可以找不到参考来了解正在发生的事情...有人可以帮助我吗?
this my problem i have a class X that inherits UITableViewController class and a class Y that inherits the X class, when i try to override a method in the Y class the method in the X class is invoked... and i can't find references to understand what's happening... can anyone help me?
提前谢谢！
代码！
mluListBuilder.h
#import <UIKit/UIKit.h>
@interface mluListBuilder : UITableViewController {
NSString *sListTitle;
NSString *sEntityName;
NSArray *aEntityProperties;
NSMutableArray *maListRecords;
NSManagedObjectContext *mocList;
NSFetchRequest *frListRecords;
NSEntityDescription *edListRecords;
NSArray *aOrderByProperties;
NSArray *aToolBarItems;
NSArray *aToolBarItemsActions;
}
@property (nonatomic, retain) NSString *sListTitle;
@property (nonatomic, retain) NSString *sEntityName;
@property (nonatomic, retain) NSArray *aEntityProperties;
@property (nonatomic, retain) NSMutableArray *maListRecords;
@property (nonatomic, retain) NSManagedObjectContext *mocList;
@property (nonatomic, retain) NSFetchRequest *frListRecords;
@property (nonatomic, retain) NSEntityDescription *edListRecords;
@property (nonatomic, retain) NSArray *aOrderByProperties;
@property (nonatomic, retain) NSArray *aToolBarItems;
@property (nonatomic, retain) NSArray *aToolBarItemsActions;
- (id) initWithStyle: (UITableViewStyle) style
listTitle: (NSString *) psListTitle
entityName: (NSString *) psEntityName
entityProperties: (NSArray *) paEntityProperties
orderListByProperties: (NSArray *) paOrderByProperties
toolBarItems: (NSArray *) paToolBarItems
toolBarItemsActions: (NSArray *) paToolBarItemsActions;
- (void)newRecord;
- (void)deleteRecord;
@end
mluListBuilder.m
#import "mluListBuilder.h"
@implementation mluListBuilder
@synthesize sListTitle,
sEntityName,
aEntityProperties,
maListRecords,
mocList,
frListRecords,
edListRecords,
aOrderByProperties,
aToolBarItems,
aToolBarItemsActions;
- (id) initWithStyle: (UITableViewStyle) style
listTitle: (NSString *) psListTitle
entityName: (NSString *) psEntityName
entityProperties: (NSArray *) paEntityProperties
orderListByProperties: (NSArray *) paOrderByProperties
toolBarItems: (NSArray *) paToolBarItems
toolBarItemsActions: (NSArray *) paToolBarItemsActions
{
sListTitle = psListTitle;
sEntityName = psEntityName;
aEntityProperties = paEntityProperties;
aOrderByProperties = paOrderByProperties;
aToolBarItems = paToolBarItems;
aToolBarItemsActions = paToolBarItemsActions;
if (self = [super initWithStyle:style]) {
}
return self;
}
- (void)viewDidLoad {
self.title = NSLocalizedString(sListTitle, nil);
if ([aToolBarItems count] > 0) {
NSMutableArray *maToolBarItems = [[NSMutableArray alloc] init];
self.navigationController.toolbarHidden = NO;
for (int i = 0; i < [aToolBarItems count]; i++) {
UIBarButtonItem * bbiToolBarItem = [[UIBarButtonItem alloc]
initWithTitle:NSLocalizedString([aToolBarItems objectAtIndex:i], nil)
style:UIBarButtonItemStyleBordered
target:self
action:NSSelectorFromString([aToolBarItemsActions objectAtIndex:i])
];
[maToolBarItems addObject:bbiToolBarItem];
}
self.toolbarItems = maToolBarItems;
} else {
self.navigationController.toolbarHidden = YES;
}
if (mocList != nil) {
frListRecords = [[NSFetchRequest alloc] init];
NSSortDescriptor *sdListRecords = [[NSSortDescriptor alloc] initWithKey:@"name" ascending:YES];
[frListRecords setSortDescriptors:[[NSArray alloc] initWithObjects:sdListRecords, nil]];
edListRecords = [NSEntityDescription entityForName:sEntityName inManagedObjectContext:mocList];
[frListRecords setEntity:edListRecords];
NSError *errFetchRequest;
maListRecords = [[mocList executeFetchRequest:frListRecords error:&errFetchRequest] mutableCopy];
}
[super viewDidLoad];
}
- (void)viewWillAppear:(BOOL)animated {
NSError *errFetchRequest;
maListRecords = [[mocList executeFetchRequest:frListRecords error:&errFetchRequest] mutableCopy];
[self.tableView reloadData];
if (self.navigationController.toolbarHidden == YES) {
if ([aToolBarItems count] > 0) {
self.navigationController.toolbarHidden = NO;
}
}
}
- (void)didReceiveMemoryWarning {
// Releases the view if it doesn't have a superview.
[super didReceiveMemoryWarning];
// Release any cached data, images, etc that aren't in use.
}
- (void)viewDidUnload {
// Release any retained subviews of the main view.
// e.g. self.myOutlet = nil;
}
#pragma mark Table view methods
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
return 1;
}
// Customize the number of rows in the table view.
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
return [maListRecords count];
}
// Customize the appearance of table view cells.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = @"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
}
for (UIView *vwExisting in cell.contentView.subviews) {
[vwExisting removeFromSuperview];
}
NSEntityDescription *edCurrentRecord = [maListRecords objectAtIndex:indexPath.row];
UILabel *lblCell = [[UILabel alloc] initWithFrame:CGRectMake(5.0, 5.0, 280, 20.0)];
[lblCell setText:edCurrentRecord.name];
[cell.contentView addSubview:lblCell];
[cell setSelectionStyle:UITableViewCellSelectionStyleNone];
return cell;
}
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
// Navigation logic may go here. Create and push another view controller.
// AnotherViewController *anotherViewController = [[AnotherViewController alloc] initWithNibName:@"AnotherView" bundle:nil];
// [self.navigationController pushViewController:anotherViewController];
// [anotherViewController release];
}
- (void)dealloc {
[super dealloc];
}
- (void)newRecord {
NSLog(@"%@", [self class]);
}
- (void)deleteRecord {
}
@end
mluLawyerCaseSituationsList.h
#import <Foundation/Foundation.h>
#import "mluListBuilder.h";
@interface mluLawyerCaseSituationsList : mluListBuilder {
}
- (void)newRecord;
@end
mluLawyerCaseSituationsList.m
#import "mluLawyerCaseSituationsList.h"
@implementation mluLawyerCaseSituationsList
- (void)newRecord {
NSLog(@"%@", [self class]);
}
@end
调用mluLawyerCaseSituationsList
mluLawyerCaseSituationsList *vcCaseSituations = [[mluListBuilder alloc]
initWithStyle:UITableViewStylePlain
listTitle:@"titCaseSituations"
entityName:@"case_situations"
entityProperties:[[NSArray alloc] initWithObjects:@"name", nil]
orderListByProperties:[[NSArray alloc] initWithObjects:@"name", nil]
toolBarItems:[[NSArray alloc] initWithObjects:@"btNew", nil]
toolBarItemsActions:[[NSArray alloc] initWithObjects:@"newRecord", nil]
];
输出...:(
2009-12-17 17:30:02.726 mluLawyer [2862:20b] mluListBuilder
希望有帮助...
推荐答案
我只是简要地浏览了一下您的代码，但是从代码和输出看，您显然分配了类X的实例(mluListBuilder).
I’ve been looking through your code only briefly, but it seems obvious (from code and from the output) that you allocate an instance of class X (mluListBuilder).
当然，您不能期望拥有Y类(mluLawyerCaseSituationsList)的方法，该方法是在Y从X派生而对象是X类时执行的.
Of course, you cannot expect to have a method of class Y (mluLawyerCaseSituationsList), performed when Y is derived from X and the object is of class X.
这篇关于尝试覆盖Objective-C(iPhone)中的方法时出现问题的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
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