在具有下标的UILabel上调用方法sizeToFit不起作用

Question

我有一个UILabel的子类,它应该在用户输入内容时更新其文本.当然,随着文本长度的增加,标签的大小必须调整以适应文本.我调用了sizeToFit方法,当标签正确调整其宽度时,文本的底部被切断.问题是,该文本包括标和上标,标签不与在考虑下标调整本身(例如,用H 2 O两者的底部被切断).

我可以覆盖sizeToFit或sizeThatFits:来增加标签的高度吗？

编辑:

- (void) addCompound {

self.currentLabel = [[FormulaLabel alloc] initWithFrame:CGRectMake(10, 10, 100, 50)];

[self addSubview:self.currentLabel];

[self.currentLabel sizeToFit];

// Right now self.currentlabel.text = "". However, I've confirmed thru NSLogging that letters are added to self.currentLabel.text as the user types on the keyboard. Also, the text displays properly (as long as it's within the original frame) when I remove [sel.currentLabel sizeToFit]

}

Answer 1

您应该在子类中重写 UILabel 方法 (CGSize)sizeThatFits:(CGSize)size，如下例所示。我只是在 UILabel 计算的高度上加上 10pt 以容纳下标。

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@implementation ESKLabel\n- (CGSize)sizeThatFits:(CGSize)size\n{\n    CGSize theSize = [super sizeThatFits:size];\n    return CGSizeMake(theSize.width, theSize.height + 10);\n}\n@end\n

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示例输出：

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self.eskLabel.text = @"Hello Long\xc2\xb2 Long\\u2082 World";\nNSLog(@"CGSize: %@", NSStringFromCGSize(self.eskLabel.frame.size));\n[self.eskLabel sizeToFit];\nNSLog(@"CGSize: %@", NSStringFromCGSize(self.eskLabel.frame.size));\n

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来自 NSLog：

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This GDB was configured as "x86_64-apple-darwin".sharedlibrary apply-load-rules all Attaching to process 864. \n2012-01-06 23:34:21.949 Stackoverflow4[864:f803] CGSize: {85, 61} \n2012-01-06 23:34:21.951 Stackoverflow4[864:f803] CGSize: {302, 44} \nkill \nquit\n

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