我想设置一个UILabel的左插图/边距,但找不到这样做的方法。标签有一个背景集,所以仅仅改变它的原点是行不通的。这将是理想的插入文本10px左右在左手边。


当前回答

我通过子类化UILabel和重写drawTextInRect来解决这个问题:

- (void)drawTextInRect:(CGRect)rect {
    UIEdgeInsets insets = {0, 5, 0, 5};
    [super drawTextInRect:UIEdgeInsetsInsetRect(rect, insets)];
}

斯威夫特3.1:

override func drawText(in rect: CGRect) {
    let insets = UIEdgeInsets.init(top: 0, left: 5, bottom: 0, right: 5)
    super.drawText(in: UIEdgeInsetsInsetRect(rect, insets))
}

斯威夫特4.2.1:准备

override func drawText(in rect: CGRect) {
    let insets = UIEdgeInsets(top: 0, left: 5, bottom: 0, right: 5)
    super.drawText(in: rect.inset(by: insets))
}

你可能已经猜到了,这是对tc的改编。的答案。它有两个优点:

没有必要通过发送sizeToFit消息来触发它 它只保留标签框架——如果你的标签有背景,而你不想让它缩小,这很方便

其他回答

没有子类和所有的爵士。我动态地做了这个:

[cell.textLabel setTranslatesAutoresizingMaskIntoConstraints:NO];
[cell.textLabel constraintTrailingEqualTo:cell.contentView constant:-100];

约束部分只是一个简单的代码糖纸(我们有相同的方法从上/下/左/右添加填充)..如果我在这里得到足够的爱,我将开放整个包装:

- (id)constraintTrailingEqualTo:(UIView *)toView constant:(CGFloat)constant
{
    NSLayoutConstraint *cn = [NSLayoutConstraint constraintWithItem:self
                                                          attribute:NSLayoutAttributeTrailing
                                                          relatedBy:NSLayoutRelationEqual
                                                             toItem:toView
                                                          attribute:NSLayoutAttributeTrailing
                                                         multiplier:1 constant:constant];

    [toView addConstraint:cn];
    return self;
}

(注意,我是在

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath: (NSIndexPath *)indexPath;

你可能需要调用[self setNeedsLayout];这取决于你的语境。

这适用于多行标签:

class PaddedLabel: UILabel {
    var verticalPadding: CGFloat = 0
    var horizontalPadding: CGFloat = 0

    override func drawText(in rect: CGRect) {
        let insets = UIEdgeInsets(top: verticalPadding, left: horizontalPadding, bottom: verticalPadding, right: horizontalPadding)
        super.drawText(in: UIEdgeInsetsInsetRect(rect, insets))
    }

    override var intrinsicContentSize: CGSize {
        get {
            let textWidth = super.intrinsicContentSize.width - horizontalPadding * 2
            let textHeight = sizeThatFits(CGSize(width: textWidth, height: .greatestFiniteMagnitude)).height
            let width = textWidth + horizontalPadding * 2
            let height = textHeight + verticalPadding * 2
            return CGSize(width: frame.width, height: height)
        }
    }
}

Swift 3 &自动布局兼容版本:

class InsetLabel: UILabel {

    var insets = UIEdgeInsets()

    convenience init(insets: UIEdgeInsets) {
        self.init(frame: CGRect.zero)
        self.insets = insets
    }

    convenience init(dx: CGFloat, dy: CGFloat) {
        let insets = UIEdgeInsets(top: dy, left: dx, bottom: dy, right: dx)
        self.init(insets: insets)
    }

    override func drawText(in rect: CGRect) {
        super.drawText(in: UIEdgeInsetsInsetRect(rect, insets))
    }

    override var intrinsicContentSize: CGSize  {
        var size = super.intrinsicContentSize
        size.width += insets.left + insets.right
        size.height += insets.top + insets.bottom
        return size
    }
}

在Swift中,它是这样解决的。

class Label: UILabel {
    override func drawTextInRect(rect: CGRect) {
        super.drawTextInRect(UIEdgeInsetsInsetRect(rect, UIEdgeInsets(top: 0, left: 10, bottom: 0, right: 10)))
    }
}

很多答案都很复杂。在某些情况下,这是必要的。然而,如果你正在阅读这篇文章,你的标签没有左右边距,你只是想要一点填充,这里是整个解决方案:

第一步:在结尾添加空格(按几次空格键)

步骤2:设置标签的文本对齐方式为居中

Done