首先导入已经封装好的两个文件GrayPageControl.h，GrayPageControl.m，里面继承了UIPageControl，重写了他的方法。文件内容如下：

GrayPageControl.h：

#import <Foundation/Foundation.h>

@interface GrayPageControl : UIPageControl {

    UIImage* activeImage;

    UIImage* inactiveImage;

}

@end

GrayPageControl.m：

#import “GrayPageControl.h”

@implementation GrayPageControl

-(id) initWithCoder:(NSCoder *)aDecoder

{

    self = [super initWithCoder:aDecoder];

    activeImage = [[UIImage imageNamed:@"inactive_page_image.png"] retain];

    inactiveImage = [[UIImage imageNamed:@"active_page_image.png"] retain];

    [self setCurrentPage:1];

    return self;

}

 

 

-(void) updateDots

{

    for (int i = 0; i < [self.subviews count]; i++)

    {

        UIImageView* dot = [self.subviews objectAtIndex:i];

        if (i == self.currentPage) dot.image = activeImage;

        else dot.image = inactiveImage;

    }

}

-(void) setCurrentPage:(NSInteger)page

{

    [super setCurrentPage:page];

    [self updateDots];

}

-(void)dealloc

{

    [super dealloc];

}

@end

在主程序中，只要程序把GrayPageControl的对象当做UIPageControl的对象做就可以了，另外注意，关联控件的时候 要继承GrayPageControl类