如何在UILabel之上添加UILabel

Question

如果我设置了bottomLabel.text =中文字符，我在运行它时看不到aboveLabel，如果我调试视图层次结构，我可以看到it.so，问题是什么？

    UILabel *bottomLabel  = [[UILabel alloc]initWithFrame:CGRectMake(0, 100, 200, 40)];
    bottomLabel.backgroundColor = [UIColor redColor];
    bottomLabel.text = @"中文";
    [self.view addSubview:bottomLabel];   
    UILabel *aboveLabel = [[UILabel alloc]initWithFrame:CGRectMake(0, 0, 60, 30)];
    aboveLabel.backgroundColor = [UIColor greenColor];
    aboveLabel.text = @"aboveLabel";
    [bottomLabel addSubview:aboveLabel];

Answer 1

您正在添加aboveLabel作为bottomLabel的子视图，因此当您将汉字分配给它时，它不会显示。您可以看到它的视图层次结构，因为它被分配了一个框架，并添加为子视图。如果要在UILabel之上添加一个UILabel，可以将两个标签添加为公共父视图的子视图。即

[self.view addSubview:bottomLabel]; 
[self.view addSubview:aboveLabel];

Answer 2

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为什么你不用NSMutableAttributedString来做这个只有一个标签。

NSString *text1 = @"Hello";
NSString *date1 = @"                                               12.05 Pm\n";

NSString *text2 = @"World";
NSString *date2 = @"                                               11.00 AM";


self.lbl.numberOfLines = 0;

NSString * str = [text1 stringByAppendingString:date1];
NSString * str2 = [text2 stringByAppendingString:date2];



UIFont *text1Font = [UIFont fontWithName:@"HelveticaNeue-Medium" size:10];
NSMutableAttributedString *attributedString1 = [[NSMutableAttributedString alloc] initWithString: str attributes:@{ NSFontAttributeName : text1Font }];
NSMutableParagraphStyle *paragraphStyle1 = [[NSMutableParagraphStyle alloc] init];
[paragraphStyle1 setAlignment: NSTextAlignmentLeft];
[paragraphStyle1 setLineSpacing:1];
[attributedString1 addAttribute:NSParagraphStyleAttributeName value: paragraphStyle1 range:NSMakeRange(0, [attributedString1 length])];


UIFont *text2Font = [UIFont fontWithName:@"HelveticaNeue-Medium" size:10];
NSMutableAttributedString *attributedString2 = [[NSMutableAttributedString alloc] initWithString: str2 attributes:@{NSFontAttributeName : text2Font }];
NSMutableParagraphStyle *paragraphStyle2 = [[NSMutableParagraphStyle alloc] init];
[paragraphStyle2 setLineSpacing:1];
[paragraphStyle2 setAlignment: NSTextAlignmentLeft];
[attributedString2 addAttribute:NSParagraphStyleAttributeName value: paragraphStyle2 range:NSMakeRange(0, [attributedString2 length])];

   [attributedString1 appendAttributedString:attributedString2];

   [self.lbl setAttributedText:attributedString1];

Answer 3

您正在尝试将aboveLabel添加到bottomLabel.Instead中，将两者添加到一个视图或self.view中。