ios 文本不在 UILabel 中垂直居中
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Text not vertically centered in UILabel
提问by Loadex
I've created a Label with the following code :
我用以下代码创建了一个标签：
func setupValueLabel() {
valueLabel.numberOfLines = 1
valueLabel.font = UIFont(name: "Avenir-Black", size: 50)
valueLabel.adjustsFontSizeToFitWidth = true
valueLabel.clipsToBounds = true
valueLabel.backgroundColor = UIColor.greenColor()
valueLabel.textColor = valuesColor
valueLabel.textAlignment = NSTextAlignment.Center
}
I don't really understand why but the label is not vertically centered :
我真的不明白为什么，但标签不是垂直居中：
Do I have to do anything specific so it can be centered ?
我是否必须做任何特定的事情才能使其居中？
回答by rintaro
The problem is that font size is shrunk by adjustsFontSizeToFitWidth = true, but it does not adjust the lineHeightautomatically. It remains to be for original font size that is 50.
问题是字体大小缩小了adjustsFontSizeToFitWidth = true，但它不会lineHeight自动调整。它仍然是原始字体大小，即50.
By default, the text is aligned to its baseline. you can adjust it with baselineAdjustmentproperty.
默认情况下，文本与其基线对齐。你可以用baselineAdjustment属性来调整它。
In your case, you should set it to UIBaselineAdjustment.alignCenters.
在您的情况下，您应该将其设置为UIBaselineAdjustment.alignCenters.
valueLabel.baselineAdjustment = .alignCenters
回答by otiai10
Thanks to @rintaro, it works finally.
感谢@rintaro，它终于奏效了。
One more thing for my case, it didn't work because I was setting ByWordWrapping. I had to set lineBreakModeas ByClipping.
对于我的情况还有一件事，它不起作用，因为我正在设置ByWordWrapping. 我必须设置lineBreakMode为ByClipping.
