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言归正传，iOS开发中，UIButton是很常用的控件，经常会碰到图片和文字结合的情况，系统默认的是图片在左，文字在右，并且中间间距很小，并不能满足我们的需要，于是封装了一个AlignButton控件，只需要指定alignType和padding就能控制图片和文字的位置和间距，关键代码如下：
// left、right、top、bottom指的是title的位置
typedef NS_ENUM(NSInteger,AlignType)
{
AlignType_TextRight = 1, //title在右边
AlignType_TextLeft, //title在左边
AlignType_TextTop, //title在上面
AlignType_TextBottom, //title在下面
};
@interface AlignButton : UIButton
@property (nonatomic,assign) AlignType alignType; //文字title所在位置
@property (assign, nonatomic) CGFloat padding; //图片和文字间距
@end
.m文件
- (void)layoutSubviews
{
[super layoutSubviews];
CGRect titleRect= [self titleRectForContentRect:self.bounds];
CGRect imgRect = [self imageRectForContentRect:self.bounds];
switch (self.alignType) {
case AlignType_TextRight: //字体居右，图片居左
{
[self setImageEdgeInsets:UIEdgeInsetsMake(0, -self.padding, 0, 0)];
[self setTitleEdgeInsets:UIEdgeInsetsMake(0, self.padding, 0, 0)];
//针对RTL的情况，当然也可以判断isRTL，重新计算frame
}
break;
case AlignType_TextLeft: //文字居左，图片居右边
{
[self setImageEdgeInsets:UIEdgeInsetsMake(0, titleRect.size.width + self.padding, 0, -titleRect.size.width)];
[self setTitleEdgeInsets:UIEdgeInsetsMake(0, -imgRect.size.width - self.padding, 0, imgRect.size.width)];
}
break;
case AlignType_TextTop: //文字居上，图片居下
{
self.titleLabel.textAlignment = NSTextAlignmentCenter;
CGFloat height = imgRect.size.height + self.padding + titleRect.size.height;
self.titleLabel.frame = CGRectMake(0, (CGRectGetHeight(self.frame) - height) / 2, CGRectGetWidth(self.frame), CGRectGetHeight(self.titleLabel.frame));
self.imageView.frame = CGRectMake((CGRectGetWidth(self.frame) - imgRect.size.width) / 2, CGRectGetMaxY(self.titleLabel.frame) + self.padding, imgRect.size.width, imgRect.size.height);
}
break;
case AlignType_TextBottom: //文字居下，图片居上
{
self.titleLabel.textAlignment = NSTextAlignmentCenter;
CGFloat height = imgRect.size.height + self.padding + titleRect.size.height;
self.imageView.frame = CGRectMake((CGRectGetWidth(self.frame) - imgRect.size.width) / 2, (CGRectGetHeight(self.frame) - height) / 2, imgRect.size.width, imgRect.size.height);
self.titleLabel.frame = CGRectMake(0, CGRectGetMaxY(self.imageView.frame) + self.padding, CGRectGetWidth(self.frame), CGRectGetHeight(self.titleLabel.frame));
}
break;
default:
break;
}
/* <#注释#>
Note: that doesn’t actually flip the UIImage, but instead configures the image to be drawn flipped when it’s placed inside a UIImageView.
注意：图片并没有翻转，当放置到imageView的时候image才会被翻转
*/
if (isRTL()) {
if (@available(iOS 9.0,*)) {
self.imageView.image = [self.imageView.image imageFlippedForRightToLeftLayoutDirection];
}
}
}
void RTLMethodSwizzling (id obj,SEL oriMethod,SEL newMethod){
Method ori = class_getInstanceMethod([obj class], oriMethod);
Method new = class_getInstanceMethod([obj class], newMethod);
method_exchangeImplementations(ori, new);
}
//RTL布局：hook方法setImageEdgeInsets:和setTitleEdgeInsets:
+ (void)load
{
if (isRTL()) {
[AlignButton swizzlingOriMethod:@selector(setContentEdgeInsets:) newMethod:@selector(rtl_setContentEdgeInsets:)];
[AlignButton swizzlingOriMethod:@selector(setImageEdgeInsets:) newMethod:@selector(rtl_setImageEdgeInsets:)];
[AlignButton swizzlingOriMethod:@selector(setTitleEdgeInsets:) newMethod:@selector(rtl_setTitleEdgeInsets:)];
}
}
+ (void)swizzlingOriMethod:(SEL)ori newMethod:(SEL)new
{
Method originalMethod = class_getInstanceMethod([self class], ori);
Method newMethod = class_getInstanceMethod([self class], new);
method_exchangeImplementations(originalMethod, newMethod);
}
- (void)rtl_setContentEdgeInsets:(UIEdgeInsets)contentEdgeInsets {
[self rtl_setContentEdgeInsets:RTLEdgeInsetsWithInsets(contentEdgeInsets)];
}
- (void)rtl_setImageEdgeInsets:(UIEdgeInsets)imageEdgeInsets {
[self rtl_setImageEdgeInsets:RTLEdgeInsetsWithInsets(imageEdgeInsets)];
}
- (void)rtl_setTitleEdgeInsets:(UIEdgeInsets)titleEdgeInsets {
[self rtl_setTitleEdgeInsets:RTLEdgeInsetsWithInsets(titleEdgeInsets)];
}
安装：
1、使用Cocoapods安装:
platform :ios
pod 'AlignButton'
2、手动安装：
直接拷贝AlignButton文件夹（包含AlignButton.h、AlignButton.m文件）到工程项目中.
使用: 引用头文件：#import "AlignButton.h"
#import "AlignButton.h"
@interface ViewController ()
@property (weak, nonatomic) IBOutlet AlignButton *rightBtn;
@property (weak, nonatomic) IBOutlet AlignButton *leftBtn;
@property (weak, nonatomic) IBOutlet AlignButton *topBtn;
@property (weak, nonatomic) IBOutlet AlignButton *bottomBtn;
@property (weak, nonatomic) IBOutlet AlignButton *imageBtn;
@property (weak, nonatomic) IBOutlet AlignButton *titleBtn;
@end
- (void)viewDidLayoutSubviews
{
[super viewDidLayoutSubviews];
self.rightBtn.alignType = AlignType_TextRight;
self.rightBtn.padding = 10;
self.rightBtn.imageView.backgroundColor = [UIColor cyanColor];
self.rightBtn.titleLabel.backgroundColor = [UIColor redColor];
self.leftBtn.imageView.backgroundColor = [UIColor cyanColor];
self.leftBtn.titleLabel.backgroundColor = [UIColor redColor];
self.leftBtn.alignType = AlignType_TextLeft;
self.leftBtn.padding = 10;
self.topBtn.alignType = AlignType_TextTop;
self.topBtn.padding = 10;
self.bottomBtn.alignType = AlignType_TextBottom;
self.bottomBtn.padding = 10;
}
效果如图：
image.png
RTL布局： 做国际化语言适配时，可能会遇到RTL（RightToLeft）布局的情况，大部分国家语言读取都是从左向右LTR（LeftToRight），但有些国家的语言读取是从右向左RTL读取的，如阿拉伯语。
解决思路：判断是否需要RTL布局，hook UIButton的方法setImageEdgeInsets:和setTitleEdgeInsets:来达到RTL重新布局的效果：
image.png
转载请注明出处，谢谢！
