我想在两行文本的左边放置一个图标，这样在图像和文本开始之间有大约2-3像素的空间。控件本身水平居中对齐(通过接口生成器设置)
这个按钮应该是这样的:
| |
|[Image] Add To |
| Favorites |
我试图配置这与contenttedgeinset, imageEdgeInsets和titleEdgeInsets无效。我知道，负值会使边缘扩大，而正值会使边缘缩小，使边缘更接近中心。
我试着:
[button setTitleEdgeInsets:UIEdgeInsetsMake(0, -image.size.width, 0, 0)];
[button setImageEdgeInsets:UIEdgeInsetsMake(0, button.titleLabel.bounds.size.width, 0, 0)];
但这并没有正确显示它。我一直在调整这些值，但从-5到-10的左插入值似乎不会以预期的方式移动它。-10将文本一直向左移动，所以我期望-5将它从左侧移动一半，但事实并非如此。
嵌套背后的逻辑是什么?我不熟悉图像放置和相关术语。
我用这个SO问题作为参考，但我的价值观有些不对。
UIButton:如何使用imageEdgeInsets和titleEdgeInsets居中图像和文本?
我的垂直定心方法:
extension UIButton {
/// Layout image and title with vertical centering.
/// - Parameters:
/// - size: The button size.
/// - imageTopOffset: Top offset for image.
/// - spacing: Distance between image and title.
func verticalAlignmentByCenter(size: CGSize, imageTopOffset: CGFloat, spacing: CGFloat) {
let contentRect = contentRect(forBounds: CGRect(origin: .zero, size: size))
let imageRect = imageRect(forContentRect: contentRect)
let titleRect = titleRect(forContentRect: contentRect)
let imageTop = imageTopOffset - imageRect.origin.y
let imageLeft = contentRect.width/2 - imageRect.width/2
imageEdgeInsets = UIEdgeInsets(top: imageTop, left: imageLeft, bottom: 0, right: 0)
let titleTop = imageTopOffset + spacing + imageRect.height - titleRect.origin.y
let titleLeft = titleRect.origin.x - contentRect.width/2 - titleRect.width/2
titleEdgeInsets = UIEdgeInsets(top: titleTop, left: titleLeft, bottom: 0, right: 0)
}
}
在swift 5.3和@ravron的启发下回答:
extension UIButton {
/// Fits the image and text content with a given spacing
/// - Parameters:
/// - spacing: Spacing between the Image and the text
/// - contentXInset: The spacing between the view to the left image and the right text to the view
func setHorizontalMargins(imageTextSpacing: CGFloat, contentXInset: CGFloat = 0) {
let imageTextSpacing = imageTextSpacing / 2
contentEdgeInsets = UIEdgeInsets(top: 0, left: (imageTextSpacing + contentXInset), bottom: 0, right: (imageTextSpacing + contentXInset))
imageEdgeInsets = UIEdgeInsets(top: 0, left: -imageTextSpacing, bottom: 0, right: imageTextSpacing)
titleEdgeInsets = UIEdgeInsets(top: 0, left: imageTextSpacing, bottom: 0, right: -imageTextSpacing)
}
}
它增加了一个额外的水平边距，从视图到图像，从标签到视图
@ravron非常出色地给出了这个答案。
在我的例子中，我不仅需要在图像和标题之间添加水平宽度，还需要在按钮的“开头”和“结尾”添加水平空间。
因此，我使用了内部图像和标签的intrinsicContentSize:
接收视图的自然大小，只考虑视图本身的属性。
| |
|[LEADING SPACE] [Image] [SPACE BETWEEN IMAGE AND TITLE] Add To [TRAILING SPACE]|
| Favorites |
let leadingTrailingSpace = 10
let horizontalWidthBetweenImageAndTitle = 4
let insetAmount = horizontalWidthBetweenImageAndTitle / CGFloat(2)
button.imageEdgeInsets = UIEdgeInsets(top: 0, left: -CGFloat(insetAmount), bottom: 0, right: insetAmount);
button.titleEdgeInsets = UIEdgeInsets(top: 0, left: CGFloat(insetAmount), bottom: 0, right: -insetAmount);
button.contentEdgeInsets = UIEdgeInsets(top: 0, left: CGFloat(insetAmount), bottom: 0, right: insetAmount);
let buttonWidth =
(button.titleLabel?.intrinsicContentSize.width ?? 0) +
(button.imageView?.intrinsicContentSize.width ?? 0)
+ insetAmount
+ leadingTrailingSpace
button.widthAnchor.constraint(equalToConstant: buttonWidth).isActive = true
