如何在UILabel的末尾添加更多按鈕？

Question

我一直在爲此工作很長一段時間。 我需要展開並摺疊UILabel文本，點擊位於文本末尾的按鈕UILabel。

認爲我試過 我已經使用VSWordDetector來檢測哪個單詞的UILabel被點擊，但它沒有給出正確的單詞點擊。

Answer 1

我建議你只用UIButton而不可見的框架與titleLabel.text@"..."或@"▼"。 因此，例如，您有一個字符串@"Some long long, really long string which couldn't be presented in one line"。然後取UILabel文本的子字符串，並在標籤的右側放置上述按鈕。添加▼-buuton的動作以更新label.text並隱藏按鈕。 代碼片段：

@interface YourClass 

@property (strong, nonatomic) UILabel* longStringLabel; 
@property (strong, nonatomic) UIButton* moreButton; 
@property (strong, nonatomic) NSString* text; 

@end 

@implementation YourClass 

// Some method, where you add subviews, for example viewDidLoad 
{ 
// ... 
    self.longStringLabel.frame = CGRectMake(0, 0, 100, 44); 
    [self addSubview:self.longStringLabel]; 

    self.moreButton.frame = CGRectMake(CGRectGetMaxX(self.longStringLabel.frame), 0, 20, 44); 
    [self addSubview:self.moreButton]; 
// ... 
} 

- (UILabel*)longStringLabel 
{ 
    if (!_longStringLabel) 
    { 
     _longStringLabel = [UILabel new]; 
     _longStringLabel.lineBreakMode = NSLineBreakByTruncatingTail; 
    } 

    return _longStringLabel; 
} 

- (UIButton*)moreButton 
{ 
    if (!_moreButton) 
    { 
     _moreButton = [UIButton buttonWithType:UIButtonTypeCustom]; 
     _moreButton.titleLabel.text = @"▼"; 
     [_moreButton addTarget:self action:@selector(moreButtonDidTap:) forControlEvents:UIControlEventTouchUpInside]; 
    } 
    return _moreButton; 
} 

- (void)moreButtonDidTap:(UIButton*)sender 
{ 
    self.longStringLabel.frame = [self.text boundingRectWithSize:CGSizeMake(self.longStringLabel.frame.size.width + self.moreButton.frame.size.width, 100) 
                 options:NSStringDrawingUsesLineFragmentOrigin 
                 attributes:@{ NSFontAttributeName : self.longStringLabel.font } 
                 context:nil]; 
    self.longStringLabel.text = self.text; 

    self.moreButton.hidden = YES; 
} 

@end