如果可以避免,我不想使用子视图。我想要一个带有背景图像,文本和图像的UIButton。现在,当我这样做的时候,图像在文本的左边。背景图像、文本和图像都有不同的高亮状态。


当前回答

由于转换解决方案在iOS 11中不起作用,我决定编写一种新的方法。

调整按钮semanticContentAttribute可以让我们很好地将图像放到右边,而不必在文本更改时重新布局。因此它是理想溶液。然而,我仍然需要RTL的支持。事实上,一个应用程序不能改变它的布局方向在同一会话解决这个问题很容易。

话虽如此,它还是相当直截了当的。

extension UIButton {
    func alignImageRight() {
        if UIApplication.shared.userInterfaceLayoutDirection == .leftToRight {
            semanticContentAttribute = .forceRightToLeft
        }
        else {
            semanticContentAttribute = .forceLeftToRight
        }
    }
}

其他回答

Swift 4 & 5

改变UIButton图像的方向(RTL和LTR)

extension UIButton {
    func changeDirection(){
       isArabic ? (self.contentHorizontalAlignment = .right) : (self.contentHorizontalAlignment = .left)
        // left-right margin 
        self.imageEdgeInsets = UIEdgeInsets(top: 0, left: 5, bottom: 0, right: 5)
        self.titleEdgeInsets = UIEdgeInsets(top: 0, left: 5, bottom: 0, right: 5)
    }
}

这里提到的解决方案停止工作,一旦我启用自动布局。我不得不提出我自己的想法:

子类UIButton和覆盖layoutSubviews方法:

//
//  MIThemeButtonImageAtRight.m
//  Created by Lukasz Margielewski on 7/9/13.
//

#import "MIThemeButtonImageAtRight.h"

static CGRect CGRectByApplyingUIEdgeInsets(CGRect frame, UIEdgeInsets insets);

@implementation MIThemeButtonImageAtRight

- (void)layoutSubviews
{
    [super layoutSubviews];

    CGRect contentFrame = CGRectByApplyingUIEdgeInsets(self.bounds, self.contentEdgeInsets);

    CGRect frameIcon = self.imageView.frame;
    CGRect frameText = self.titleLabel.frame;

    frameText.origin.x = CGRectGetMinX(contentFrame) + self.titleEdgeInsets.left;
    frameIcon.origin.x = CGRectGetMaxX(contentFrame) - CGRectGetWidth(frameIcon);

    self.imageView.frame = frameIcon;
    self.titleLabel.frame = frameText;
}

@end

static CGRect CGRectByApplyingUIEdgeInsets(CGRect frame, UIEdgeInsets insets){

    CGRect f = frame;

    f.origin.x += insets.left;
    f.size.width -= (insets.left + insets.right);
    f.origin.y += (insets.top);
    f.size.height -= (insets.top + insets.bottom);

    return f;

}

结果:

最简单的解决方案:

iOS 10及以上版本,Swift:

button.transform = CGAffineTransform(scaleX: -1.0, y: 1.0)
button.titleLabel?.transform = CGAffineTransform(scaleX: -1.0, y: 1.0)
button.imageView?.transform = CGAffineTransform(scaleX: -1.0, y: 1.0)

在iOS 10之前,Swift/Obj-C:

button.transform = CGAffineTransformMakeScale(-1.0, 1.0);
button.titleLabel.transform = CGAffineTransformMakeScale(-1.0, 1.0);
button.imageView.transform = CGAffineTransformMakeScale(-1.0, 1.0);

iOS 9及以上版本,Swift:(推荐)

button.semanticContentAttribute = .forceRightToLeft

我把功劳都给了inspirre48。基于他的建议和其他问题,我想出了这个。子类UIButton并重写这些方法。

@implementation UIButtonSubclass

- (CGRect)imageRectForContentRect:(CGRect)contentRect
{
    CGRect frame = [super imageRectForContentRect:contentRect];
    frame.origin.x = CGRectGetMaxX(contentRect) - CGRectGetWidth(frame) -  self.imageEdgeInsets.right + self.imageEdgeInsets.left;
    return frame;
}

- (CGRect)titleRectForContentRect:(CGRect)contentRect
{
    CGRect frame = [super titleRectForContentRect:contentRect];
    frame.origin.x = CGRectGetMinX(frame) - CGRectGetWidth([self imageRectForContentRect:contentRect]);
    return frame;
}

@end

在Piotr Tomasik的优雅解决方案的基础上:如果你想在按钮标签和图像之间有一点间距,那么包括在你的边缘嵌入如下(复制我的代码在这里完美地为我工作):

    CGFloat spacing          = 3;
    CGFloat insetAmount      = 0.5 * spacing;

    // First set overall size of the button:
    button.contentEdgeInsets = UIEdgeInsetsMake(0, insetAmount, 0, insetAmount);
    [button sizeToFit];

    // Then adjust title and image insets so image is flipped to the right and there is spacing between title and image:
    button.titleEdgeInsets   = UIEdgeInsetsMake(0, -button.imageView.frame.size.width - insetAmount, 0,  button.imageView.frame.size.width  + insetAmount);
    button.imageEdgeInsets   = UIEdgeInsetsMake(0, button.titleLabel.frame.size.width + insetAmount, 0, -button.titleLabel.frame.size.width - insetAmount);

感谢Piotr的解决方案!

Erik