方法一：分类法（使用runtime，但是调用了私有的API方法，上传appstroe会被拒的）
#import "UIPageControl+space.h"
#import <objc/runtime.h>
@implementation UIPageControl (space)
+ (void)load
{
Method origin = class_getInstanceMethod([self class], @selector(_indicatorSpacing));
Method custom = class_getInstanceMethod([self class], @selector(custom_indicatorSpacing));
method_exchangeImplementations(origin, custom);
}
- (double)custom_indicatorSpacing
{
return 12.0;
}
@end
方法二：继承法（继承UIPageControl,通过layoutSubviews从新布局）
#import "CLPageControl.h"
#define dotW 7
#define magrin 5
@implementation CLPageControl
- (void)layoutSubviews
{
[super layoutSubviews];
//计算圆点间距
CGFloat marginX = dotW + magrin;
//计算整个pageControll的宽度
CGFloat newW = (self.subviews.count - 1 ) * marginX;
//设置新frame
self.frame = CGRectMake(self.frame.origin.x, self.frame.origin.y, newW, self.frame.size.height);
//设置居中
CGPoint center = self.center;
center.x = self.superview.center.x;
self.center = center;
//遍历subview,设置圆点frame
for (int i=0; i<[self.subviews count]; i++) {
UIImageView* dot = [self.subviews objectAtIndex:i];
if (i == self.currentPage) {
[dot setFrame:CGRectMake(i * marginX, dot.frame.origin.y, dotW, dotW)];
}else {
[dot setFrame:CGRectMake(i * marginX, dot.frame.origin.y, dotW, dotW)];
}
}
}