小编Mic*_*ael的帖子

我正在尝试将手势识别器附加到我自己的类,这是UILabel的子类,但它不起作用.你能帮我理解代码中的错误吗？

 
@interface Card : UILabel  {

}

- (void) addBackSideWord;

@end

#import "Card.h"

@implementation Card
- (id)initWithFrame:(CGRect)frame {

    if ((self = [super initWithFrame:frame])) {

        UITapGestureRecognizer *tapRecognizer = [[UITapGestureRecognizer alloc]
                         initWithTarget:self action:@selector(addBackSideWord)];
        [tapRecognizer setNumberOfTouchesRequired:2];
        [tapRecognizer setDelegate:self];
        [self addGestureRecognizer:tapRecognizer];
    }

    return self;
}

- (void) addBackSideWord {

     //do something
}
@end

这是一张简单的图纸

    

- (void)drawRect:(CGRect)rect
{
    //vertical line with 1 px stroking
    UIBezierPath *vertLine = [[UIBezierPath alloc] init];
    [vertLine moveToPoint:CGPointMake(20.0, 10.0)];
    [vertLine addLineToPoint:CGPointMake(20.0, 400.0)];
    vertLine.lineWidth = 1.0;
    [[UIColor blackColor] setStroke];
    [vertLine stroke];

    //vertical rectangle 1px width 
    UIBezierPath *vertRect= [UIBezierPath bezierPathWithRect:CGRectMake(40.0, 10.0, 1.0, 390.0)];
    [[UIColor blackColor] setFill];
    [vertRect fill];

}

在非视网膜3GS和模拟器上,第一行是模糊的,看起来比1 px宽,但第二行是清晰的.

不幸的是我没有iPhone4和新iPad进行测试,但在视网膜模拟器上两条线看起来都一样.

问题:矩形而非中风是获得非视网膜和视网膜设备相同结果的唯一方法吗？

简化:名为cards的表中有3列.

id packTitle term

id是一列 - 从0到100的整数

packTitle - 描述包的字符串,假设有3种包PACK1,PACK2,PACK3

术语 - 101个项目的不同未分类名称.

通过SQL语句

select packTitle from cards group by packTitle;

我可以获得3个项目的清单.

你能否建议NSPredicate相当于SQL语句GROUP BY.我需要在UITableView中填充一个数组.

我的代码:

- (void)viewDidLoad {

    [super viewDidLoad];

    CGRect rectFake = CGRectZero;

    UITextField *fakeField = [[UITextField alloc] initWithFrame:rectFake];

    [self.view addSubview:fakeField];

    UIView *av = [[UIView alloc] initWithFrame:CGRectMake(0.0, 0.0, 0.0, 39.0)];

    av.backgroundColor = [UIColor darkGrayColor];

    CGRect rect = CGRectMake(200.0, 4.0, 400.0, 31.0);

    UITextField *textField = [[UITextField alloc] initWithFrame:rect];

    textField.borderStyle = UITextBorderStyleRoundedRect;

    textField.font = [UIFont systemFontOfSize:24.0];

    textField.delegate = self;

    [av addSubview:textField];

    fakeField.inputAccessoryView = av;

    [fakeField becomeFirstResponder];

}

我试着补充一下

[textField becomeFirstResponder] 

最后,但它没有用.

在按下ENTER时委托方法隐藏键盘的另一个问题也不起作用.

- (BOOL) textFieldShouldReturn:(UITextField *)textField {

    [textField resignFirstResponder];

    return YES;
}

UITextView是模态控制器视图的子视图.我需要在键盘出现时降低UITextView高度,以使UITextView的底部边框y坐标等于键盘的顶部y坐标.我想要键盘高度

CGRect frameBegin = [[notification.userInfo objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue] ;
CGRect frameEnd = [[notification.userInfo objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue];

CGRect resultBegin = [self.view convertRect:frameBegin fromView:nil];
CGRect resultEnd = [self.view convertRect:frameEnd fromView:nil];

CGFloat kbdHeight = resultBegin.origin.y  - resultEnd.origin.y;

问题是当键盘出现时,此模态视图会跳起来.在这种情况下如何计算键盘的顶部边框坐标？

现在我正在尝试以下它,它的工作原理.

    - (void)findDictionaryWithValueForKey:(NSString *)name {

         for (NSDictionary * set in myArray) {

            if ([[set objectForKey:@"title"] isEqualToString:name]) 
               \\do something

         }

    }

编辑: 我在bshirley的帖子中添加了一个额外的参数.现在它看起来更灵活.

- (NSDictionary *)findDictionaryWithValue:(NSString*)name forKey:(NSString *)key {

    __block BOOL found = NO;
    __block NSDictionary *dict = nil;

    [self.cardSetsArray enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
        dict = (NSDictionary *)obj;
        NSString *title = [dict valueForKey:key];
        if ([title isEqualToString:name]) {
            found = YES;
            *stop = YES;
        }
    }];

    if (found) {
        return dict;
    } else {
        return nil;
    } …

这个简单的问题困扰着我.吸气剂是否相同

@property (nonatomic, retain) NSString *name
@property (nonatomic, copy) NSString *name 

- (NSString*) name{
    return name;    
}