objective-c实现无限循环轮播器（objective-c实现无限循环轮播器）

先看看效果图：

具体实现代码：

1. 控制器

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 // // appdelegate.m // 无限轮播器 // // created by zhangmi on 16/5/16. // copyright © 2016年 paramount pictures. all rights reserved. // #import "viewcontroller.h" #import "sninfinitescrollview.h" @interface viewcontroller () @end @implementation viewcontroller - (void)viewdidload { [super viewdidload]; // do any additional setup after loading the view, typically from a nib. nsmutablearray * images = [nsmutablearray array]; for (int i = 0; i < 5; i++) { nsstring * imagename = [nsstring stringwithformat:@"ad_%02d", i]; //img01 uiimage * image = [uiimage imagenamed:imagename]; [images addobject:image]; } uiview * scrollview = [sninfinitescrollview scrollviewwithframe:cgrectmake(0, 20, 414, 200) superview:self.view images:images scrolldirection:scrolldirectionhorizontal pageindicatortintcolor:[uicolor lightgraycolor] currentpageindicatortintcolor:[uicolor orangecolor] imageviewcontentmode:uiviewcontentmodescaleaspectfit]; [self.view addsubview:scrollview]; } @end

2. 显示内容界面设置

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 // // appdelegate.m // 无限轮播器 // // created by zhangmi on 16/5/16. // copyright © 2016年 paramount pictures. all rights reserved. // #import "sninfinitescrollview.h" static int const imageviewcount = 3; #define scrollviewwidth self.scrollview.frame.size.width #define scrollviewheight self.scrollview.frame.size.height @interface sninfinitescrollview () <uiscrollviewdelegate> @property(weak, nonatomic) uiscrollview * scrollview; @property(weak, nonatomic) nstimer * timer; /** pageindex */ @property(nonatomic, assign) nsinteger pageindex; @end @implementation sninfinitescrollview - (void)setimages:(nsarray<uiimage *> *)images { _images = images; // 设置页码 self.pageindex = 0; // 设置内容 [self updatecontent]; // 开始定时器 [self starttimer]; } /** 代码创建的时候调用. */ - (instancetype)initwithframe:(cgrect)frame { if (self = [super initwithframe:frame]) { // 滚动视图 uiscrollview * scrollview = [[uiscrollview alloc] init]; self.scrollview = scrollview; scrollview.delegate = self; // scroller属性 scrollview.showshorizontalscrollindicator = no; scrollview.showsverticalscrollindicator = no; scrollview.pagingenabled = yes; scrollview.bounces = no; // 添加scrollview [self addsubview:scrollview]; // 图片控件 for (int i = 0; i < imageviewcount; i++) { uiimageview * imageview = [[uiimageview alloc] init]; // 图片不变形处理. imageview.contentmode = self.imageviewcontentmode; [scrollview addsubview:imageview]; } } return self; } /** 布局子控件, 只执行一次 */ - (void)layoutsubviews { [super layoutsubviews]; self.scrollview.frame = self.bounds; if (self.scrolldirection == scrolldirectionvertical) { self.scrollview.contentsize = cgsizemake(0, imageviewcount * self.bounds.size.height); } else { self.scrollview.contentsize = cgsizemake(imageviewcount * self.bounds.size.width, 0); } for (int i = 0; i < imageviewcount; i++) { uiimageview * imageview = self.scrollview.subviews[i]; if (self.scrolldirection == scrolldirectionvertical) { imageview.frame = cgrectmake(0, i * self.scrollview.frame.size.height, self.scrollview.frame.size.width, self.scrollview.frame.size.height); } else { imageview.frame = cgrectmake(i * self.scrollview.frame.size.width, 0, self.scrollview.frame.size.width, self.scrollview.frame.size.height); } } // 设置内容 [self updatecontent]; } #pragma mark - 内容更新 - (void)updatecontent { // 设置图片 for (int i = 0; i < self.scrollview.subviews.count; i++) { nsinteger pageindex = self.pageindex; // 遍历每一个imageview uiimageview * imageview = self.scrollview.subviews[i]; if (i == 0) { pageindex--; } else if (i == 2) { pageindex++; } if (pageindex < 0) { pageindex = self.images.count - 1; } else if (pageindex >= self.images.count) { pageindex = 0; } // 图片角标赋值给 imageview的tag imageview.tag = pageindex; imageview.image = self.images[imageview.tag]; } // 设置偏移量在中间 // 不能使用带动画 contentoffset if (self.scrolldirection == scrolldirectionvertical) { self.scrollview.contentoffset = cgpointmake(0, scrollviewheight); } else { self.scrollview.contentoffset = cgpointmake(scrollviewwidth, 0); } } #pragma mark - <uiscrollviewdelegate> - (void)scrollviewdidscroll:(uiscrollview *)scrollview { // 找出最中间的那个图片控件 nsinteger page = self.pageindex; cgpoint point = cgpointzero; for (int i = 0; i < self.scrollview.subviews.count; i++) { uiimageview * imageview = self.scrollview.subviews[i]; point = [scrollview convertpoint:imageview.frame.origin toview:self.superview]; //=****** other way ****************** stone *** if (self.scrolldirection == scrolldirectionvertical) { if (abs(point.y - self.frame.origin.y) < 1.0) { page = imageview.tag; } } else { if (abs(point.x - self.frame.origin.x) < 1.0) { page = imageview.tag; } } } self.pageindex = page; self.pagecontrol.currentpage = page; //拖动结束会调用 [self updatecontent]; //#warning mark - 没有动画正常 , 有动画不动, 一直是原点 // [self updatecontent]; // 没有动画正常 , 有动画不动, 一直是原点 } /** 开始拖拽 */ - (void)scrollviewwillbegindragging:(uiscrollview *)scrollview { // 停止定时器 [self stoptimer]; } /** 结束拖拽 */ - (void)scrollviewdidenddragging:(uiscrollview *)scrollview willdecelerate:(bool)decelerate { // 开启定时器 [self starttimer]; } /** 减速完毕 */ - (void)scrollviewdidenddecelerating:(uiscrollview *)scrollview { // 更新内容 , 如果contentoffset 不带动画的话不走这个方法 [self updatecontent]; } /** 结束滚动动画 */ // 这是保险的做法吧... 如果contentoffset 不带动画的话不走这个方法 - (void)scrollviewdidendscrollinganimation:(uiscrollview *)scrollview { // 更新内容 [self updatecontent]; } #pragma mark - 定时器处理 - (void)starttimer { nstimer * timer = [nstimer scheduledtimerwithtimeinterval:1.0 target:self selector:@selector(next:) userinfo:nil repeats:yes]; // [[nsrunloop mainrunloop] addtimer:timer formode:nsrunloopcommonmodes]; [[nsrunloop currentrunloop] addtimer:timer formode:nsrunloopcommonmodes]; self.timer = timer; } - (void)stoptimer { [self.timer invalidate]; self.timer = nil; } - (void)next:(nstimer *)timer { if (self.scrolldirection == scrolldirectionvertical) { [self.scrollview setcontentoffset:cgpointmake(0, 2 * self.scrollview.frame.size.height) animated:yes]; } else { [self.scrollview setcontentoffset:cgpointmake(2 * self.scrollview.frame.size.width, 0) animated:yes]; } } //=****** 简单调用 ****************** stone *** + (instancetype)scrollviewwithframe:(cgrect)frame superview:(uiview *)superview images:(nsarray<uiimage *> *)images scrolldirection:(scrolldirection)scrolldirection pageindicatortintcolor:(uicolor *)pageindicatortintcolor currentpageindicatortintcolor:(uicolor *)currentpageindicatortintcolor imageviewcontentmode:(uiviewcontentmode)imageviewcontentmode { //=****** 添加自定义scrollview ****************** stone *** sninfinitescrollview * scrollview = [[sninfinitescrollview alloc] init]; scrollview.frame = frame; scrollview.imageviewcontentmode = imageviewcontentmode; scrollview.scrolldirection = scrolldirection; //=****** 添加image ****************** stone *** scrollview.images = images; //=****** 添加pagecontrol ****************** stone *** uipagecontrol * pagecontrol = [[uipagecontrol alloc] init]; scrollview.pagecontrol = pagecontrol; pagecontrol.enabled = no; pagecontrol.currentpageindicatortintcolor = currentpageindicatortintcolor; pagecontrol.pageindicatortintcolor = pageindicatortintcolor; pagecontrol.numberofpages = scrollview.images.count; pagecontrol.bounds = cgrectmake(0, 0, scrollview.bounds.size.width, 44); pagecontrol.center = cgpointmake(scrollview.bounds.size.width * 0.5, scrollview.bounds.size.height * 0.9); [scrollview addsubview:pagecontrol]; [superview addsubview:scrollview]; //=************************ stone *** return scrollview; } @end