我正在尝试从苹果开发者计划中完成“你的第二个 iOS 应用程序”教程。它是一个基本的 tableView 应用程序。我的问题是应用程序正在成功构建并且没有警告，但是我无法从主视图中获取详细视图。我已经复制并粘贴了 segue 标识符和苹果提供的代码。segue 正在使用 push，我已将其删除并重试了几次。我正在模拟器中测试应用程序。
如何判断 segue 是否有效？
每次我将代码从 Xcode 复制/粘贴到堆栈溢出问题文本区域时，我都会在底部收到警告说代码必须缩进 4 个空格？？？这是否意味着我必须逐行缩进代码？我做了 control + k 并粘贴在突出显示的区域，但是我仍然收到警告？？
运行模拟器并查看它时，我试图通过单击它来使用披露指示器，我是否必须推动一些特殊的东西，例如 control = click 或 command = click 等？
这是 BirdsMasterViewController.m 文件的代码：
//
// BirdsMasterViewController.m
// BirdWatching
//
// Created by David Hall on 11/13/12.
// Copyright (c) 2012 David Hall. All rights reserved.
//
#import "BirdsMasterViewController.h"
#import "BirdsDetailViewController.h"
#import "BirdSightingDataController.h"
#import "BirdSighting.h"
/*
@interface BirdsMasterViewController () {
NSMutableArray *_objects;
}
@end
*/
@implementation BirdsMasterViewController
- (void)awakeFromNib
{
[super awakeFromNib];
self.dataController = [[BirdSightingDataController alloc] init];
}
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
/*
self.navigationItem.leftBarButtonItem = self.editButtonItem;
UIBarButtonItem *addButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAdd target:self action:@selector(insertNewObject:)];
self.navigationItem.rightBarButtonItem = addButton;
*/
}
- (void)viewDidUnload
{
[super viewDidUnload];
// Release any retained subviews of the main view.
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
return (interfaceOrientation != UIInterfaceOrientationPortraitUpsideDown);
}
/*- (void)insertNewObject:(id)sender
{
if (!_objects) {
_objects = [[NSMutableArray alloc] init];
}
[_objects insertObject:[NSDate date] atIndex:0];
NSIndexPath *indexPath = [NSIndexPath indexPathForRow:0 inSection:0];
[self.tableView insertRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationAutomatic];
}
*/
#pragma mark - Table View
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
return [self.dataController countOfList];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = @"BirdSightingCell";
static NSDateFormatter *formatter = nil;
if (formatter == nil)
{
formatter = [[NSDateFormatter alloc] init];
[formatter setDateStyle:NSDateFormatterMediumStyle];
}
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
BirdSighting *sightingAtIndex = [self.dataController objectInListAtIndex:indexPath.row];
[[cell textLabel] setText:sightingAtIndex.name];
[[cell detailTextLabel] setText:[formatter stringFromDate:(NSDate *)sightingAtIndex.date]];
return cell;
}
- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath
{
// Return NO if you do not want the specified item to be editable.
return NO;
}
/*- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath
{
if (editingStyle == UITableViewCellEditingStyleDelete) {
[_objects removeObjectAtIndex:indexPath.row];
[tableView deleteRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationFade];
} else if (editingStyle == UITableViewCellEditingStyleInsert) {
// Create a new instance of the appropriate class, insert it into the array, and add a new row to the table view.
}
}
*/
/*
// 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;
}
*/
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
if ([[segue identifier] isEqualToString:@"ShowSightingDetails"]) {
BirdsDetailViewController *detailViewController = [segue destinationViewController];
detailViewController.sighting = [self.dataController objectInListAtIndex:[self.tableView indexPathForSelectedRow].row];
}
}
@end
这是 BirdsDetailViewController.m 的代码
//
// BirdSightingDataController.m
// BirdWatching
//
// Created by David Hall on 11/25/12.
// Copyright (c) 2012 David Hall. All rights reserved.
//
#import "BirdSightingDataController.h"
#import "BirdSighting.h"
@interface BirdSightingDataController ()
- (void)initializeDefaultDataList;
@end
@implementation BirdSightingDataController
- (void)initializeDefaultDataList
{
NSMutableArray *sightingList = [[NSMutableArray alloc] init];
self.masterBirdSightingList = sightingList;
BirdSighting *sighting;
NSDate *today = [NSDate date];
sighting = [[BirdSighting alloc] initWithName:@"Pigeon" location:@"Everywhere" date:today];
[self addBirdSightingWithSighting:sighting];
}
- (void)setMasterBirdSightingList:(NSMutableArray *)newList
{
if (_masterBirdSightingList != newList)
{
_masterBirdSightingList = [newList mutableCopy];
}
}
- (id)init
{
if (self = [super init])
{
[self initializeDefaultDataList];
return self;
}
return nil;
}
- (NSUInteger)countOfList
{
return [self.masterBirdSightingList count];
}
- (BirdSighting *)objectInListAtIndex:(NSUInteger)theIndex
{
return [self.masterBirdSightingList objectAtIndex:theIndex];
}
- (void)addBirdSightingWithSighting:(BirdSighting *)sighting
{
[self.masterBirdSightingList addObject:sighting];
}
@end
大卫霍尔
