使用 plist 并尝试返回数据时，我有这种奇怪的行为。为了给你一个概述，plist 在每个对象中有 12 个条目，所以我希望有 12 个，但我得到 13 个，第一个结果为空，而其余 12 个实际上是正确的。
这是我的 plist 文件：
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>Name</key>
<array>
<string>Audit</string>
<string>Tax</string>
<string>Digital</string>
<string>Consulting</string>
<string>Risk Advisory</string>
<string>Finance</string>
<string>Audit</string>
<string>Tax</string>
<string>Digital</string>
<string>Consulting</string>
<string>Advisory</string>
<string>Finance</string>
</array>
<key>Logo</key>
<array>
<string>page.png</string>
<string>page.png</string>
<string>page.png</string>
<string>page.png</string>
<string>page.png</string>
<string>page.png</string>
<string>page.png</string>
<string>page.png</string>
<string>page.png</string>
<string>page.png</string>
<string>page.png</string>
<string>page.png</string>
</array>
</dict>
</plist>
这是我的 ViewController.h 文件：
#import <UIKit/UIKit.h>
#import "iCarousel.h"
@interface PackViewController : UIViewController <iCarouselDataSource, iCarouselDelegate>
{
NSMutableArray *packName;
NSMutableArray *packLogo;
}
@property (nonatomic, retain) IBOutlet iCarousel *carousel;
@property (nonatomic, retain) NSMutableArray *packName;
@property (nonatomic, retain) NSMutableArray *packLogo;
@end
然后，这是我的 ViewController.m 文件：
#import "PackViewController.h"
#import "AsyncImageView.h"
@interface PackViewController () <UIActionSheetDelegate>
@property (nonatomic, assign) BOOL wrap;
@property (nonatomic, retain) NSMutableArray *items;
@end
@implementation PackViewController
@synthesize carousel, wrap, items;
@synthesize packName, packLogo;
- (void)awakeFromNib
{
//set up data
wrap = YES;
NSString *plistPath = [[NSBundle mainBundle] pathForResource:@"Pack" ofType:@"plist"];
NSArray *plistItems = [NSDictionary dictionaryWithContentsOfFile:plistPath];
NSArray *plistData = [plistItems valueForKey:@"Name"];
self.items = [NSMutableArray array];
for (int i = 0; i < [plistData count]; i++)
{
[items addObject:[NSNumber numberWithInt:i]];
NSLog(@"First Index Name %@",[items objectAtIndex:i]);
}
}
- (void)dealloc
{
carousel.delegate = nil;
carousel.dataSource = nil;
[carousel release];
[super dealloc];
}
#pragma mark -
#pragma mark View lifecycle
- (void)viewDidLoad
{
[super viewDidLoad];
// Pack.plist code
// get paths from root direcory
NSArray *paths = NSSearchPathForDirectoriesInDomains (NSDocumentDirectory, NSUserDomainMask, YES);
// get documents path
NSString *documentsPath = [paths objectAtIndex:0];
// get the path to our Pack.plist file
NSString *plistPath = [documentsPath stringByAppendingPathComponent:@"Pack.plist"];
// check to see if Pack.plist exists in documents
if (![[NSFileManager defaultManager] fileExistsAtPath:plistPath])
{
// if not in documents, get property list from main bundle
plistPath = [[NSBundle mainBundle] pathForResource:@"Pack" ofType:@"plist"];
}
// read property list into memory as an NSData object
NSData *plistXML = [[NSFileManager defaultManager] contentsAtPath:plistPath];
NSString *errorDesc = nil;
NSPropertyListFormat format;
// convert static property list into dictionary object
NSDictionary *temp = (NSDictionary *)[NSPropertyListSerialization
propertyListFromData:plistXML
mutabilityOption:NSPropertyListMutableContainersAndLeaves
format:&format
errorDescription:&errorDesc];
if (!temp)
{
NSLog(@"Error reading plist: %@, format: %d", errorDesc, format);
}
// assign values
self.packName = [NSMutableArray arrayWithArray:[temp objectForKey:@"Name"]];
self.packLogo = [NSMutableArray arrayWithArray:[temp objectForKey:@"Logo"]];
// configure carousel
carousel.type = iCarouselTypeInvertedWheel;
carousel.vertical = true;
}
- (void)viewDidUnload
{
[super viewDidUnload];
self.carousel = nil;
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
return YES;
}
#pragma mark -
#pragma mark UIActionSheet methods
- (void)actionSheet:(UIActionSheet *)actionSheet didDismissWithButtonIndex:(NSInteger)buttonIndex
{
if (buttonIndex >= 0)
{
//map button index to carousel type
iCarouselType type = buttonIndex;
//carousel can smoothly animate between types
[UIView beginAnimations:nil context:nil];
carousel.type = type;
[UIView commitAnimations];
}
}
#pragma mark -
#pragma mark iCarousel methods
- (NSUInteger)numberOfItemsInCarousel:(iCarousel *)carousel
{
//NSLog(@"numberOfItemsInCarousel count: %i", [items count]);
return [items count];
}
- (UIView *)carousel:(iCarousel *)carousel viewForItemAtIndex:(NSUInteger)index reusingView:(UIView *)view
{
UIButton *button = (UIButton *)view;
UILabel *label = nil;
if (button == nil)
{
//no button available to recycle, so create new one
UIImage *image = [UIImage imageNamed:[NSString stringWithFormat:@"%@", [packLogo objectAtIndex:index]]];
//NSLog(@"companyLogo: %@", [packLogo objectAtIndex:index]);
button = [UIButton buttonWithType:UIButtonTypeCustom];
button.frame = CGRectMake(0.0f, 0.0f, image.size.width, image.size.height);
[button setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
[button setBackgroundImage:image forState:UIControlStateNormal];
button.titleLabel.font = [button.titleLabel.font fontWithSize:20];
[button addTarget:self action:@selector(buttonTapped:) forControlEvents:UIControlEventTouchUpInside];
label = [[[UILabel alloc] initWithFrame:view.bounds] autorelease];
label.backgroundColor = [UIColor clearColor];
label.textAlignment = UITextAlignmentCenter;
}
else
{
//get a reference to the label in the recycled view
label = (UILabel *)[view viewWithTag:1];
}
//set button label
[button setTitle:[self.packName objectAtIndex:index] forState:UIControlStateNormal];
NSLog(@"companyName: %@", [items objectAtIndex:index]);
return button;
}
#pragma mark -
#pragma mark item tap event
- (void)buttonTapped:(UIButton *)sender
{
//get item index for button
NSInteger index = [carousel indexOfItemViewOrSubview:sender];
[[[[UIAlertView alloc] initWithTitle:@"Button Tapped"
message:[NSString stringWithFormat:@"You tapped button number %i", index]
delegate:nil
cancelButtonTitle:@"OK"
otherButtonTitles:nil] autorelease] show];
}
- (CATransform3D)carousel:(iCarousel *)_carousel itemTransformForOffset:(CGFloat)offset baseTransform:(CATransform3D)transform
{
CGFloat count = _carousel.numberOfVisibleItems;
CGFloat spacing = 1.0f;
CGFloat arc = M_PI * 2.0f;
CGFloat radius = _carousel.itemWidth * spacing * count / arc;
CGFloat angle = arc / count * offset;
return CATransform3DTranslate(transform, radius - radius * cos(angle), radius * sin(angle), 0.0f);
}
- (CGFloat)carousel:(iCarousel *)_carousel valueForOption:(iCarouselOption)option withDefault:(CGFloat)value
{
//customise carousel display
switch (option)
{
case iCarouselOptionWrap:
{
//normally you would hard-code this to YES or NO
return wrap;
}
case iCarouselOptionSpacing:
{
//add a bit of spacing between the item views
return value * 1.05f;
}
case iCarouselOptionFadeMax:
{
if (carousel.type == iCarouselTypeCustom)
{
//set opacity based on distance from camera
return 0.0f;
}
return value;
}
default:
{
return value;
}
}
}
@end
你可以看到我的 M 文件中有两行代码输出两个 NSLog 项。这些是：
NSLog(@"First Index Name %@",[items objectAtIndex:i]);
NSLog(@"companyName: %@", [items objectAtIndex:index]);
awakeFromNib 的 for 循环中包含的“第一个索引名称”的输出是：
2013-05-21 22:43:23.875 Pack[7496:c07] First Index Name 0
2013-05-21 22:43:23.877 Pack[7496:c07] First Index Name 1
2013-05-21 22:43:23.878 Pack[7496:c07] First Index Name 2
2013-05-21 22:43:23.879 Pack[7496:c07] First Index Name 3
2013-05-21 22:43:23.880 Pack[7496:c07] First Index Name 4
2013-05-21 22:43:23.880 Pack[7496:c07] First Index Name 5
2013-05-21 22:43:23.881 Pack[7496:c07] First Index Name 6
2013-05-21 22:43:23.881 Pack[7496:c07] First Index Name 7
2013-05-21 22:43:23.882 Pack[7496:c07] First Index Name 8
2013-05-21 22:43:23.882 Pack[7496:c07] First Index Name 9
2013-05-21 22:43:23.883 Pack[7496:c07] First Index Name 10
2013-05-21 22:43:23.883 Pack[7496:c07] First Index Name 11
如您所见，我以正确的顺序获得了所有 12 个值，这是我对第二个值的期望，但这就是问题所在。对于包含在-(UIView *)carousel:(iCarousel *)carousel viewForItemAtIndex:(NSUInteger)index reusingView:(UIView *)view我输出items数组中的第二个 NSLog只是想看看发生了什么。这就是我所看到的：
2013-05-21 22:43:23.916 Pack[7496:c07] companyName: 0
2013-05-21 22:43:23.918 Pack[7496:c07] companyName: 0
2013-05-21 22:43:23.919 Pack[7496:c07] companyName: 11
2013-05-21 22:43:23.920 Pack[7496:c07] companyName: 7
2013-05-21 22:43:23.921 Pack[7496:c07] companyName: 6
2013-05-21 22:43:23.922 Pack[7496:c07] companyName: 2
2013-05-21 22:43:23.922 Pack[7496:c07] companyName: 1
2013-05-21 22:43:23.923 Pack[7496:c07] companyName: 10
2013-05-21 22:43:23.924 Pack[7496:c07] companyName: 9
2013-05-21 22:43:23.925 Pack[7496:c07] companyName: 8
2013-05-21 22:43:23.925 Pack[7496:c07] companyName: 5
2013-05-21 22:43:23.926 Pack[7496:c07] companyName: 4
2013-05-21 22:43:23.927 Pack[7496:c07] companyName: 3
同样，前两个结果都是两者0，并且与第一次迭代不同，排序非常混乱。我在 SO 上发现了一个线程，其中提到 plist 不一定按顺序输出，因为它们只是关键对象，所以我明白了，但核心问题是前两个结果。
如果我更改我的 NSLog 以输出self.packName（如下所示：）的结果，NSLog(@"companyName: %@", [self.packName objectAtIndex:index]);则返回以下内容：
2013-05-21 22:49:43.663 Pack[7543:c07] companyName: (null)
2013-05-21 22:49:43.665 Pack[7543:c07] companyName: Audit
2013-05-21 22:49:43.666 Pack[7543:c07] companyName: Finance
2013-05-21 22:49:43.667 Pack[7543:c07] companyName: Tax
2013-05-21 22:49:43.668 Pack[7543:c07] companyName: Audit
2013-05-21 22:49:43.669 Pack[7543:c07] companyName: Digital
2013-05-21 22:49:43.669 Pack[7543:c07] companyName: Tax
2013-05-21 22:49:43.670 Pack[7543:c07] companyName: Risk Advisory
2013-05-21 22:49:43.671 Pack[7543:c07] companyName: Consulting
2013-05-21 22:49:43.672 Pack[7543:c07] companyName: Digital
2013-05-21 22:49:43.672 Pack[7543:c07] companyName: Finance
2013-05-21 22:49:43.673 Pack[7543:c07] companyName: Risk Advisory
2013-05-21 22:49:43.673 Pack[7543:c07] companyName: Consulting
正如您再次看到的那样，第一个结果是(null)，我很难理解为什么会发生这种情况。
为了进一步调试，我运行了这个 NSLog:NSLog(@"companyName: %@", packName);以将原始结果作为数组输出，结果如下：
2013-05-21 22:52:59.284 Pack[7581:c07] companyName: (
"Audit",
"Tax",
"Digital",
"Consulting",
"Risk Advisory",
"Finance",
"Audit",
"Tax",
"Digital",
"Consulting",
"Advisory",
"Finance"
)
数组中没有(null)结果，所以我不知道这个流氓空值来自哪里。
任何帮助将不胜感激！！！！