iOS开发小功能自学之二：分页（进行封装处理）

 1 #import <UIKit/UIKit.h>
 2 @interface ZWpageView : UIView <UIScrollViewDelegate>
 3 
 4 + (instancetype)pageView;
 5 /** 图片数据 */
 6 @property (strong, nonatomic)NSArray *imageNames;  
 7 /** 其它圆点颜色 */
 8 @property (strong, nonatomic)UIColor *otherColor;
 9 /** 当前圆点颜色 */
10 @property (strong, nonatomic)UIColor *currentColor;
11 
12 @end

#import "ZWpageView.h"
@interface ZWpageView()

@property (weak, nonatomic) IBOutlet UIScrollView *scrollView;
@property (weak, nonatomic) IBOutlet UIPageControl *pageControl;
/** 定时器 */
@property (strong, nonatomic)NSTimer *timer;

@end
@implementation ZWpageView

#pragma mark - 初始化方法
+ (instancetype)pageView{
    return [[[NSBundle mainBundle] loadNibNamed:NSStringFromClass(self) owner:nil options:nil] lastObject];
}
// 当xib\storyboard创建时，会调用这个方法来初始化控件
- (instancetype)initWithFrame:(CGRect)frame{
    if (self = [super initWithFrame:frame]) {
        [self setup];
    }
    return self;
}

/**
 * 当xib\storyboard创建完毕时，会调用这个方法来初始化控件
 * 当xib\storyboard创建完毕后的初始化操作，应该在这里面进行
 */
- (void)awakeFromNib
{
    [self setup];
}
- (void)setup
{
    self.scrollView.backgroundColor = [UIColor blueColor];
    //开启定时器
    [self startTimer];
    
}

- (void)layoutSubviews{
    [super layoutSubviews];
    //设置scrollView的frame
    self.scrollView.frame = self.bounds;
    
    CGFloat imageW = self.scrollView.frame.size.width;
    CGFloat imageH = self.scrollView.frame.size.height;
    //设置pageControl
    CGFloat pageW = 100;
    CGFloat pageH = 37;
    self.pageControl.frame = CGRectMake(imageW - pageW, imageH - pageH, pageW, pageH);
    //单页时候pageControl自动隐藏
//    self.pageControl.hidesForSinglePage = YES;   //xib中可以直接勾上！！！
    
    self.scrollView.contentSize = CGSizeMake(self.imageNames.count * imageW, 0);

    for (int i=0; i<self.scrollView.subviews.count; i++) {
        UIImageView *imageView = self.scrollView.subviews[i];
        imageView.frame = CGRectMake(i * imageW, 0, imageW,imageH);
    }
}
#pragma mark - 代理

- (void)scrollViewDidScroll:(UIScrollView *)scrollView{
    self.pageControl.currentPage = (int)(self.scrollView.contentOffset.x / self.scrollView.frame.size.width + 0.5);
}
- (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView
{
    [self stopTimer];
}
- (void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate
{
    [self startTimer];
}

#pragma mark - 定时器控制

- (void)startTimer
{
    //创建定时器
    //    NSTimer *timer = [NSTimer timerWithTimeInterval:1.5 target:self selector:@selector(nextPage) userInfo:nil repeats:YES];
    //    [timer fire];         //这个方法不行，执行一次后就释放,不会保存
    self.timer = [NSTimer scheduledTimerWithTimeInterval:1.1 target:self selector:@selector(nextPage) userInfo:nil repeats:YES];
}
- (void)stopTimer
{
    [self.timer invalidate];
    self.timer = nil;
}


- (void)nextPage
{
    NSInteger page = self.pageControl.currentPage + 1;
    if (page == self.pageControl.numberOfPages) {
        page = 0;
    }
    CGPoint offset = self.scrollView.contentOffset;
    offset.x = page * self.scrollView.frame.size.width;
    [self.scrollView setContentOffset:offset animated:YES];//跳转到你所指定内容的坐标,YES表示跳转有动画
}

#pragma mark - set方法重写

- (void)setImageNames:(NSArray *)imageNames{
    _imageNames = imageNames;
    //由于可能用到多次set方法，所以重写set方法时候应该删除点之前的set方法内的内容(不要for循环删子控件)
    [self.scrollView.subviews makeObjectsPerformSelector:@selector(removeFromSuperview)];
    
    //取出图片放入到scrollView中
    for (int i = 0; i<imageNames.count; i++) {
        UIImageView *imageView = [[UIImageView alloc] init];
        imageView.image = [UIImage imageNamed:imageNames[i]];
        [self.scrollView addSubview:imageView];
    }
    //小的细节设置
    self.scrollView.showsHorizontalScrollIndicator = NO;
    self.scrollView.pagingEnabled = YES;
    self.pageControl.numberOfPages = imageNames.count;
}

- (void)setOtherColor:(UIColor *)otherColor{
    _otherColor = otherColor;
    self.pageControl.pageIndicatorTintColor = otherColor;
}
- (void)setCurrentColor:(UIColor *)currentColor{
    _currentColor = currentColor;
    self.pageControl.currentPageIndicatorTintColor = currentColor;
}
@end