支持的功能：
- 无限轮播
- 定时器轮播
- 重用
原理：利用3（0 1 2）个视图不断的切换，滑动结束的时候始终让1显示在屏幕中间。
详情请看方法[self reloadImage];
.h
#import <UIKit/UIKit.h>
typedef void (^ImageViewClick)(NSInteger index);
@interface JAScrollView : UIView
@property (nonatomic,assign)BOOL isRunloop;//是否开启定时器 default NO
@property (nonatomic,assign)NSTimeInterval dur; //default 3
@property (nonatomic,strong)UIColor *color_pageControl;
@property (nonatomic,strong)UIColor *color_currentPageControl;
@property (nonatomic,strong)ImageViewClick click;
- (instancetype)initWithFrame:(CGRect)frame
withImages:(NSArray *)images
withIsRunloop:(BOOL)isRunloop
withBlock:(ImageViewClick)block;
@end
.m
//
// JAScrollView.m
// AutomobileAccessories
//
// Created by JA on 2017/3/17.
// Copyright © 2017年 All rights reserved.
//
#import "JAScrollView.h"
#import "BaseDefine.h"
typedef enum : NSUInteger {
ScrollViewDirectionRight, /** 向右滚动*/
ScrollViewDirectionLeft, /** 向左滚动*/
}ScrollViewDirection;
@interface JAScrollView() <UIScrollViewDelegate>
@property (nonatomic,strong)UIScrollView *scrollView;
@property (nonatomic,strong)NSArray *dataArry;
@property (nonatomic,assign)NSInteger currentImageIndex;
@property (nonatomic,assign)CGFloat lastContentOffset;
@property (nonatomic,assign)ScrollViewDirection scrollDirection;
@property (nonatomic,strong)NSMutableArray *imageViews;
@property (nonatomic,assign)NSInteger imageCount;
@property (nonatomic,strong)NSTimer *timer;
@property (nonatomic,strong)UIPageControl *pageControl;
@end
@implementation JAScrollView
@synthesize color_currentPageControl = _color_currentPageControl ,
color_pageControl = _color_pageControl ;
- (instancetype)initWithFrame:(CGRect)frame
withImages:(NSArray *)images
withIsRunloop:(BOOL)isRunloop
withBlock:(ImageViewClick)block;
{
self = [super initWithFrame:frame];
if (self) {
self.dur = 3;
self.imageCount = images ? images.count : 0;
self.isRunloop = isRunloop;
self.dataArry = images;
self.click = block;
[self loadBaseView];
}
return self;
}
- (void)loadBaseView
{
self.currentImageIndex =0;
self.scrollView.contentOffset = CGPointMake(self.scrollView.frame.size.width, 0);
for (int i = 0; i<3; i ++) {
UIImageView *imageView = [[UIImageView alloc] initWithFrame:CGRectMake(i*self.scrollView.frame.size.width, 0, self.scrollView.frame.size.width, self.scrollView.frame.size.height)];
if (i == 0 && self.dataArry!=nil && self.dataArry.count > 1) {
imageView.backgroundColor = self.dataArry[self.dataArry.count - 1];//左边
}
if (i == 1 && self.dataArry!=nil && self.dataArry.count > 0) {
imageView.backgroundColor = self.dataArry[0];//中间
}
if (i == 2 && self.dataArry !=nil && self.dataArry.count > 1) {
imageView.backgroundColor = self.dataArry[1];//右边
}
[self.imageViews addObject:imageView];
[self.scrollView addSubview:imageView];
}
UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapAction)];
[self.scrollView addGestureRecognizer:tap];
[self addSubview:self.scrollView];
[self addSubview:self.pageControl];
}
#pragma mark -
#pragma mark - set
- (void)setImageCount:(NSInteger)imageCount
{
_imageCount = imageCount;
if (_imageCount < 1) {
self.scrollView.scrollEnabled = NO;
return;
}
self.scrollView.scrollEnabled = YES;
self.pageControl.numberOfPages = imageCount ;
CGSize size = [self.pageControl sizeForNumberOfPages:imageCount];
self.pageControl.bounds = CGRectMake(0, 0, size.width, size.height);
self.pageControl.center = CGPointMake(self.frame.size.width - size.width - 0. , self.frame.size.height - 20.) ;
self.pageControl.currentPage = 0;
}
- (void)setIsRunloop:(BOOL)isRunloop
{
_isRunloop = isRunloop;
if (isRunloop) {
[self createTimer];
}
}
- (void)setColor_pageControl:(UIColor *)color_pageControl
{
_color_pageControl = color_pageControl ;
self.pageControl.pageIndicatorTintColor = _color_pageControl ;
}
//default whiteColor
- (UIColor *)color_pageControl
{
if (!_color_pageControl) {
_color_pageControl = [UIColor whiteColor] ;
}
return _color_pageControl ;
}
- (void)setColor_currentPageControl:(UIColor *)color_currentPageControl
{
_color_currentPageControl = color_currentPageControl ;
self.pageControl.currentPageIndicatorTintColor = _color_currentPageControl ;
}
//default darkGrayColor
- (UIColor *)color_currentPageControl
{
if (!_color_currentPageControl) {
_color_currentPageControl = [UIColor darkGrayColor] ;
}
return _color_currentPageControl ;
}
//create timer
- (void)createTimer{
if (self.timer == nil) {
self.timer = [NSTimer scheduledTimerWithTimeInterval:self.dur target:self selector:@selector(timerAction) userInfo:nil repeats:YES];
[[NSRunLoop currentRunLoop] addTimer:self.timer forMode:NSRunLoopCommonModes];
}
}
#pragma mark -
#pragma mark - action
- (void)timerAction{
if (_imageCount <= 1) return ;
[self.scrollView setContentOffset:CGPointMake(self.scrollView.frame.size.width *2, 0) animated:YES];
[self performSelector:@selector(reloadImage) withObject:nil afterDelay:.35];
}
- (void)tapAction{
if (self.click) {
self.click(_currentImageIndex);
}
}
#pragma mark -
#pragma mark - scrollViewDelegate
- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView
{
[self reloadImage];
}
- (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView
{
// NSLog(@"开始拖拽");
[self.timer invalidate];
self.timer = nil;
}
- (void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate
{
[self createTimer];
}
- (void)reloadImage
{
if ( self.imageViews.count == 0 || self.dataArry.count == 0) {
return;
}
NSInteger leftImageIndex,rightImageIndex ;
CGPoint offset = [_scrollView contentOffset] ;
if (offset.x > self.frame.size.width)
{ // 向右滑动
_currentImageIndex = (_currentImageIndex + 1) % self.dataArry.count ;
}
else if(offset.x < self.frame.size.width)
{ // 向左滑动
_currentImageIndex = (_currentImageIndex + self.dataArry.count - 1) % self.dataArry.count ;
}
UIImageView * centerImageView = [self.imageViews objectAtIndex:1];
UIImageView *leftImageView = [self.imageViews objectAtIndex:0];
UIImageView *rightImageView = [self.imageViews objectAtIndex:2];
centerImageView.backgroundColor =self.dataArry[_currentImageIndex];
// 重新设置左右图片
leftImageIndex = (_currentImageIndex + self.dataArry.count - 1) % self.dataArry.count ;
rightImageIndex = (_currentImageIndex + 1) % self.dataArry.count ;
leftImageView.backgroundColor = self.dataArry[leftImageIndex] ;
rightImageView.backgroundColor = self.dataArry[rightImageIndex] ;
[self.scrollView setContentOffset:CGPointMake(self.scrollView.frame.size.width, 0) animated:NO];
self.pageControl.currentPage = self.currentImageIndex;
}
#pragma mark -
#pragma mark -懒加载
- (NSMutableArray *)imageViews
{
if (!_imageViews) {
_imageViews = [[NSMutableArray alloc] init];
}
return _imageViews;
}
- (UIScrollView *)scrollView
{
if (!_scrollView) {
_scrollView = [[UIScrollView alloc] init];
_scrollView.frame = CGRectMake(0, 0, self.frame.size.width, self.frame.size.height);
_scrollView.contentSize = CGSizeMake(self.frame.size.width *3, self.frame.size.height);
_scrollView.delegate = self;
_scrollView.pagingEnabled = YES;
_scrollView.showsVerticalScrollIndicator = NO;
_scrollView.showsHorizontalScrollIndicator = NO;
_scrollView.bounces = NO;
}
return _scrollView;
}
- (UIPageControl *)pageControl
{
if (!_pageControl) {
_pageControl = [[UIPageControl alloc] init] ;
_pageControl.pageIndicatorTintColor = self.color_pageControl ;
_pageControl.currentPageIndicatorTintColor = self.color_currentPageControl ;
}
return _pageControl ;
}
- (void)dealloc
{
if (self.timer) {
[self.timer invalidate];
self.timer = nil;
}
}
@end
使用方法：
//数组传字符串会crash，可以自行修改！
NSMutableArray *images = [NSMutableArray arrayWithCapacity:0];
for (int i = 0; i < 1000; i ++) {
[images addObject:[UIColor colorWithRed:arc4random()%255/255.0 green:arc4random()%255/255.0 blue:arc4random()%255/255.0 alpha:1.0]];
}
JAScrollView *scroll = [[JAScrollView alloc] initWithFrame:CGRectMake(0, 0, SCREEN_W, H) withImages:images withIsRunloop:YES withBlock:^(NSInteger index){
NSLog(@"当前点击了index:%zd",index);
}];
