小编Abd*_*que的帖子

使用以下代码行:

PayPalPayment *payment = [[PayPalPayment alloc] init];
NSLog(@"Price %@",[self.product objectForKey:@"Price"]);
NSString *string = [self.product objectForKey:@"Price"];
payment.amount = [[NSDecimalNumber alloc] initWithString:string];

我的应用程序崩溃了这个日志:

[NSDecimalNumber length]: unrecognized selector sent to instance

NSLog正在返回:

Price 96.67

真是崩溃???

I am trying to give a tag for an NSString by creating a category:

.h:

@property (nonatomic, copy) NSString *stringTag;

.m:

- (NSString *)stringTag
{
    return objc_getAssociatedObject(self, CFBridgingRetain(kStringTagKey));
}
- (void)setStringTag:(NSString *)stringTag
{
    objc_setAssociatedObject(self, CFBridgingRetain(kStringTagKey), stringTag, OBJC_ASSOCIATION_COPY_NONATOMIC);
}

However I'm getting these errors:

大家好，我试图获取键盘输入附件视图的 y 位置，如下所示：

-(void)textViewDidBeginEditing:(UITextView *)textView
{
     ipvFrame = textView.inputAccessoryView.frame;
}

-(void)textViewDidChange:(UITextView *)textView
{
     NSLog(@"Input Accessory View:%f",ipvFrame.origin.y);   
}

然而 NSLog 说 ipvFrame y 位置是 0！有人知道为什么吗？

我有一个没有标题的UITabBarItem,只有一个图像.我想知道如何更改图像大小,以便它可以占用整个UITabBarItem.

我在互联网上搜索但没有发现任何东西.

我试过了:

UIStoryboard *storyBoard = [UIStoryboard storyboardWithName:@"Main_Storyboard" bundle:nil];
UITabBarController *tabBarController = [storyBoard instantiateViewControllerWithIdentifier:@"tab"];
UITabBar *tabBar = tabBarController.tabBar;
UITabBarItem *tabBarItem1 = [tabBar.items objectAtIndex:0];
UITabBarItem *tabBarItem2 = [tabBar.items objectAtIndex:1];
UITabBarItem *tabBarItem3 = [tabBar.items objectAtIndex:2];

tabBarItem1.imageInsets = UIEdgeInsetsMake(0, -10, -6, -10);

但没有改变.

谢谢!

目的

我试图减少我的UICollectionViewCells之间的空间

我尝试了什么

我尝试了子类化UICollectionViewFlowLayout并重写此方法:

- (NSArray *) layoutAttributesForElementsInRect:(CGRect)rect {
    NSArray *answer = [[super layoutAttributesForElementsInRect:rect] mutableCopy];

    for(int i = 1; i < [answer count]; ++i) {
        UICollectionViewLayoutAttributes *currentLayoutAttributes = answer[i];
        UICollectionViewLayoutAttributes *prevLayoutAttributes = answer[i - 1];
        NSInteger maximumSpacing = 4;
        NSInteger origin = CGRectGetMaxX(prevLayoutAttributes.frame);
        if(origin + maximumSpacing + currentLayoutAttributes.frame.size.width < self.collectionViewContentSize.width) {
            CGRect frame = currentLayoutAttributes.frame;
            frame.origin.x = origin + maximumSpacing;
            currentLayoutAttributes.frame = frame;
        }
    }
    return answer;
}

然后在我的UICollectionViewController viewDidLoad中:

SublassedcollectionViewLayout *space = [[SublassedcollectionViewLayout alloc]init];
self.collectionView.collectionViewLayout = space;

问题

这只会让我的UICollectionViewCells更小. …

我试图增加这样的NSInteger使用NSUserDefaults:

NSInteger attempts = [[NSUserDefaults standardUserDefaults]integerForKey:@"tries"];
NSInteger newA = attempts++;
[[NSUserDefaults standardUserDefaults]setInteger:newA forKey:@"tries"];
[[NSUserDefaults standardUserDefaults]synchronize];
NSLog(@"Tries: %d",[[NSUserDefaults standardUserDefaults]integerForKey:@"tries"]);

不过这是我的NSLogs:

Tries: 0
Tries: 0
Tries: 0