最近在项目中，需要有个强制更新功能，更新内容，动态显示，系统的content设置，内容是居中，丑爆了！！所以自定义个UILabel，因为需要有内边距！
UILabel不像UIButton那样，有个contentEdgeInsets、titleEdgeInsets、imageEdgeInsets供我们设置文字或图片与按钮边界的界限，所以我们只能另外想其他办法来实现。其实，办法也很简单，只需要我们自定义UILabel，然后重写drawTextInRect:方法即可实现我们的目标。
如下图
图片发自简书App
UIAlertView *alert = [[UIAlertView alloc]initWithTitle:@"发现新版本"
message:nil
delegate:self
cancelButtonTitle:nil
otherButtonTitles:@"立即更新", nil];
alert.tag = 3;
DGLabel *textLabel = [[DGLabel alloc] init];
textLabel.font = [UIFont systemFontOfSize:13];
textLabel.numberOfLines =0;
textLabel.textAlignment =NSTextAlignmentLeft;
textLabel.textInsets = UIEdgeInsetsMake(0.f, 10.f, 0.f, 10.f); // 设置左内边距
textLabel.text = responseObject[@"content"];
[alert setValue:textLabel forKey:@"accessoryView"];
[alert show];
DGLabel.h
#import <UIKit/UIKit.h>
@interface DGLabel : UILabel
@property (nonatomic, assign) UIEdgeInsets textInsets; // 控制字体与控件边界的间隙
@end
DGLabel.m
#import "DGLabel.h"
@implementation DGLabel
- (instancetype)init {
if (self = [super init]) {
_textInsets = UIEdgeInsetsZero;
}
return self;
}
- (instancetype)initWithFrame:(CGRect)frame {
if (self = [super initWithFrame:frame]) {
_textInsets = UIEdgeInsetsZero;
}
return self;
}
- (void)drawTextInRect:(CGRect)rect {
[super drawTextInRect:UIEdgeInsetsInsetRect(rect, _textInsets)];
}
@end
