IOS 欢迎页（UIScrollView，UIPageControl）

本文介绍了app欢迎页的简单实现。只有第一次运行程序时才说会出现，其余时间不会出现。下面是效果图。

代码如下：（如有不明白的可以评论我，我会详细讲解）

//
//  ViewController.m
//  CX IOS欢迎页
//
//  Created by ma c on 16/3/18.
//  Copyright © 2016年 xubaoaichiyu. All rights reserved.
//

#import "ViewController.h"

@interface ViewController ()<UIScrollViewDelegate>

@property (nonatomic, strong) UIScrollView * scrollView;
@property (nonatomic, strong) UIPageControl * pageControl;

@end

@implementation ViewController
#pragma mark - life
- (void)viewDidLoad {
    [super viewDidLoad];
   //判断是否是第一次运行程序
    NSUserDefaults * userDefaults = [NSUserDefaults standardUserDefaults];
//    [userDefaults removeObjectForKey:@"FirstLoad"];
    if ([userDefaults objectForKey:@"FirstLoad"] == nil) {
        [userDefaults setBool:NO forKey:@"FirstLoad"];
        [self loadScrollView];
    }

}
#pragma mark - deleDate

-(void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView{

    CGPoint point = self.scrollView.contentOffset;

    NSInteger current = point.x / self.view.frame.size.width;

    self.pageControl.currentPage = current;

}

#pragma mark - function
-(void)loadScrollView{

    CGRect rect = [UIScreen mainScreen].bounds;

    self.scrollView = [[UIScrollView alloc]initWithFrame:rect];
    //分页
    self.scrollView.pagingEnabled = YES;

    self.scrollView.delegate = self;

    self.scrollView.showsHorizontalScrollIndicator = NO;

    self.scrollView.showsVerticalScrollIndicator = NO;
    //scrollView滚动区域大小
    self.scrollView.contentSize = CGSizeMake(rect.size.width * , rect.size.height);

    for (NSInteger i = ; i < ; i ++) {

        UIImageView * imageView = [[UIImageView alloc]init];

        imageView.frame = CGRectMake(i * rect.size.width, , rect.size.width, rect.size.height);
        //为了区别imageView而又简单操作，建立随机颜色。
        imageView.backgroundColor = [UIColor colorWithRed:arc4random() %  / .f green:arc4random() %  / .f blue:arc4random() %  / .f alpha:];
        [self.scrollView addSubview:imageView];

        //添加开启软件
        UIButton * removeBUtton = [UIButton buttonWithType:UIButtonTypeCustom];

        removeBUtton.frame = CGRectMake( +  * rect.size.width, rect.size.height * 0.7, rect.size.width - , );

        [removeBUtton setTitle:@"开启旅行" forState:UIControlStateNormal];

        [removeBUtton setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal];

        removeBUtton.backgroundColor = [UIColor orangeColor];

        [removeBUtton addTarget:self action:@selector(start) forControlEvents:UIControlEventTouchUpInside];

        [self.scrollView addSubview:removeBUtton];
    }

    [self.view addSubview:self.scrollView];

    [self loadPageControl];

}

-(void)start{

    [self.pageControl removeFromSuperview];

    [self.scrollView removeFromSuperview];

}
-(void)loadPageControl{

    CGRect rect = [UIScreen mainScreen].bounds;

    self.pageControl = [[UIPageControl alloc]init];

    self.pageControl.numberOfPages = ;

    CGSize pageControlSize = [self.pageControl sizeForNumberOfPages:];

    self.pageControl.frame = CGRectMake((rect.size.width - pageControlSize.width) / , rect.size.height * 0.8, pageControlSize.width, pageControlSize.height);

    self.pageControl.currentPage = ;

    self.pageControl.currentPageIndicatorTintColor = [UIColor greenColor];

    self.pageControl.pageIndicatorTintColor = [UIColor grayColor];

    [self.view addSubview:self.pageControl];

    [self.view bringSubviewToFront: self.pageControl];

}
@end