基于UIScrollView控件实现的滑动引导页详解手机开发

在很多的app应用开发中，当第一次启动应用的时候都会来一个引导页，其效果如下图所示。

此处，我们使用UIScrollView来实现一个这样的效果，涉及的代码有。
WelcomeViewController.h

#import <UIKit/UIKit.h>  
 
@interface WelcomeViewController : UIViewController  
 
@end 

逻辑处理WelcomeViewController.m

#import "WelcomeViewController.h"  
#define IMAGECOUNT 3  
 
@interface WelcomeViewController () <UIScrollViewDelegate>  
@property (nonatomic, strong)UIPageControl *pageControl;  
 
@end  
 
@implementation WelcomeViewController  
 
- (void)viewDidLoad {  
  [super viewDidLoad];  
  //创建ScrollView  
  UIScrollView *sv = [[UIScrollView alloc] init];  
  sv.frame = self.view.bounds;  
  //设置边缘不弹跳  
  sv.bounces = NO;  
  //整页滚动  
  sv.pagingEnabled = YES;  
  sv.showsHorizontalScrollIndicator = NO;  
 
  //加入多个子视图(ImageView)  
  for(NSInteger i=0; i<IMAGECOUNT; i++){  
    NSString *imgName = [NSString stringWithFormat:@"%ld", i+1];  
    UIImage *image = [UIImage imageNamed:imgName];  
    UIImageView *imageView = [[UIImageView alloc]initWithImage:image];  
    CGRect frame = CGRectZero;  
    frame.origin.x = i * sv.frame.size.width;  
    frame.size = sv.frame.size;  
    imageView.frame = frame;  
    [sv addSubview:imageView];  
 
    if(i==IMAGECOUNT-1){  
      //开启图片的用户点击功能  
      imageView.userInteractionEnabled = YES;  
      //加个按钮  
      UIButton *button = [[UIButton alloc]init];  
 
      button.frame = CGRectMake((imageView.frame.size.width-150)/2, imageView.frame.size.height*0.8, 150, 40);  
      button.backgroundColor = [UIColor orangeColor];  
      [button setTitle:@"立即体验" forState:UIControlStateNormal];  
      button.titleLabel.font = [UIFont boldSystemFontOfSize:16];  
      [imageView addSubview:button];  
      [button addTarget:self action:@selector(enter) forControlEvents:UIControlEventTouchUpInside];    }  
  }  
 
  sv.contentSize = CGSizeMake(IMAGECOUNT * sv.frame.size.width, sv.frame.size.height);  
 
  [self.view addSubview:sv];  
 
  //加入页面指示控件PageControl  
  UIPageControl *pageControl = [[UIPageControl alloc]init];  
  self.pageControl = pageControl;  
  //设置frame  
  pageControl.frame = CGRectMake(0, self.view.frame.size.height - 40, self.view.frame.size.width, 20);  
  //分页面的数量  
  pageControl.numberOfPages = IMAGECOUNT;  
  //设置小圆点渲染颜色  
  pageControl.pageIndicatorTintColor = [UIColor whiteColor];  
  //设置当前选中小圆点的渲染颜色  
  pageControl.currentPageIndicatorTintColor = [UIColor redColor];  
  //关闭用户点击交互  
  pageControl.userInteractionEnabled = NO;  
 
  [self.view addSubview:pageControl];  
 
  sv.delegate = self;  
 
 
}  
- (void)enter  
{  
  NSLog(@"进入应用");  
}  
 
//UIScrollViewDelegate方法  
- (void)scrollViewDidScroll:(UIScrollView *)scrollView  
{  
  CGPoint offset = scrollView.contentOffset;  
  if(offset.x<=0){  
    offset.x = 0;  
    scrollView.contentOffset = offset;  
  }  
  NSUInteger index = round(offset.x / scrollView.frame.size.width);  
  self.pageControl.currentPage = index;  
}  
 
- (void)didReceiveMemoryWarning {  
  [super didReceiveMemoryWarning];  
  // Dispose of any resources that can be recreated.  
}  
 
@end

到此，一个简单的引导页面就完成了。