如何配置UIButton的title与Image的EdgeInsets

UIEdgeInsetsMake(top,left,bottom,right),它的作用是处理控件距离容器的上左下右的距离，可以为正值也可以是负值。下面的表格展示了正负值表现的效果

titleEdgeInsets是设置button标题的内边距。
imageEdgeInsets是设置button图片的内边距

button默认是图片在左，title在右，当我们需要处理他们的相对位置时，就需要调整EdgeInsets了。
image的right时相对于title的left的，当然title的left也是相对于image的right的。其他的都是相对于容器的边框的。

下面提供的工具方便修改button里image与title的相对位置

#import <UIKit/UIKit.h>

typedef NS_ENUM(NSUInteger, ZekeButtonEdgeInsetsStyle) {
    ZekeButtonEdgeInsetsStyleTop, // image在上，label在下
    ZekeButtonEdgeInsetsStyleLeft, // image在左，label在右
    ZekeButtonEdgeInsetsStyleBottom, // image在下，label在上
    ZekeButtonEdgeInsetsStyleRight // image在右，label在左
};

@interface UIButton (ImageTitleSpacing)

/**
 *  设置button的titleLabel和imageView的布局样式，及间距
 *
 *  @param style titleLabel和imageView的布局样式
 *  @param space titleLabel和imageView的间距
 */
- (void)layoutButtonWithEdgeInsetsStyle:(ZekeButtonEdgeInsetsStyle)style
                        imageTitleSpace:(CGFloat)space;

@end

#import "UIButton+ImageTitleSpacing.h"

@implementation UIButton (ImageTitleSpacing)

- (void)layoutButtonWithEdgeInsetsStyle:(MKButtonEdgeInsetsStyle)style
                        imageTitleSpace:(CGFloat)space
{
    /**
     *  前置知识点：titleEdgeInsets是title相对于其上下左右的inset，跟tableView的contentInset是类似的，
     *  如果只有title，那它上下左右都是相对于button的，image也是一样；
     *  如果同时有image和label，那这时候image的上左下是相对于button，右边是相对于label的；title的上右下是相对于button，左边是相对于image的。
     */
    // 1. 由于iOS8中titleLabelimageView的size为0，用下面的这种设置
    CGFloat imageWith = self.imageView.intrinsicContentSize.width;
    CGFloat imageHeight = self.imageView.intrinsicContentSize.height;
    CGFloat labelWidth = self.titleLabel.intrinsicContentSize.width;
    CGFloat labelHeight = self.titleLabel.intrinsicContentSize.height;
    
    // 2. 声明全局的imageEdgeInsets和labelEdgeInsets
    UIEdgeInsets imageEdgeInsets = UIEdgeInsetsZero;
    UIEdgeInsets labelEdgeInsets = UIEdgeInsetsZero;
    
    // 3. 根据style和space得到imageEdgeInsets和labelEdgeInsets的值
    switch (style) {
        case ZekeButtonEdgeInsetsStyleTop:
        {
            imageEdgeInsets = UIEdgeInsetsMake(-labelHeight-space/2.0, 0, 0, -labelWidth);
            labelEdgeInsets = UIEdgeInsetsMake(0, -imageWith, -imageHeight-space/2.0, 0);
        }
            break;
        case ZekeButtonEdgeInsetsStyleLeft:
        {
            imageEdgeInsets = UIEdgeInsetsMake(0, -space/2.0, 0, space/2.0);
            labelEdgeInsets = UIEdgeInsetsMake(0, space/2.0, 0, -space/2.0);
        }
            break;
        case ZekeButtonEdgeInsetsStyleBottom:
        {
            imageEdgeInsets = UIEdgeInsetsMake(0, 0, -labelHeight-space/2.0, -labelWidth);
            labelEdgeInsets = UIEdgeInsetsMake(-imageHeight-space/2.0, -imageWith, 0, 0);
        }
            break;
        case ZekeButtonEdgeInsetsStyleRight:
        {
            imageEdgeInsets = UIEdgeInsetsMake(0, labelWidth+space/2.0, 0, -labelWidth-space/2.0);
            labelEdgeInsets = UIEdgeInsetsMake(0, -imageWith-space/2.0, 0, imageWith+space/2.0);
        }
            break;
        default:
            break;
    }
    // 4. 赋值
    self.titleEdgeInsets = labelEdgeInsets;
    self.imageEdgeInsets = imageEdgeInsets;
}

@end

更新时间2019-03-26