ios輪播圖片用法

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////  ZQRViewController.m//  04-圖片輪播器////  Created by apple on 17-08-24.//  Copyright (c) 2017年 zzqqrr. All rights reserved.//#define ZQRImageCount 5#import "ZQRViewController.h"@interface ZQRViewController () <UIScrollViewDelegate>@property (weak, nonatomic) IBOutlet UIScrollView *scrollView;@property (weak, nonatomic) IBOutlet UIPageControl *pageControl;/** *  定時器 */@property (nonatomic, strong) NSTimer *timer;@end@implementation ZQRViewController- (void)viewDidLoad{    [super viewDidLoad];    self.scrollView.delegate=self;    // 0.一些固定的尺寸參數    CGFloat imageW = self.scrollView.frame.size.width;    CGFloat imageH = self.scrollView.frame.size.height;    CGFloat imageY = 0;        // 1.添加5張圖片到scrollView中    for (int i = 0; i<MJImageCount; i++) {        UIImageView *imageView = [[UIImageView alloc] init];                // 設定frame        CGFloat imageX = i * imageW;        imageView.frame = CGRectMake(imageX, imageY, imageW, imageH);                // 設定圖片        NSString *name = [NSString stringWithFormat:@"img_0%d", i + 1];        imageView.image = [UIImage imageNamed:name];                [self.scrollView addSubview:imageView];    }        // 2.設定內容尺寸    CGFloat contentW = MJImageCount * imageW;    self.scrollView.contentSize = CGSizeMake(contentW, 0);        // 3.隱藏水平捲軸    self.scrollView.showsHorizontalScrollIndicator = NO;        // 4.分頁    self.scrollView.pagingEnabled = YES;//    self.scrollView.delegate = self;        // 5.設定pageControl的總頁數    self.pageControl.numberOfPages = MJImageCount;        // 6.添加定時器(每隔2秒調用一次self 的nextImage方法)    [self addTimer];}/** *  添加定時器 */- (void)addTimer{    self.timer = [NSTimer scheduledTimerWithTimeInterval:2.0 target:self selector:@selector(nextImage) userInfo:nil repeats:YES];    [[NSRunLoop currentRunLoop] addTimer:self.timer forMode:NSRunLoopCommonModes];}/** *  移除定時器 */- (void)removeTimer{    [self.timer invalidate];    self.timer = nil;}- (void)nextImage{    // 1.增加pageControl的頁碼    int page = 0;    if (self.pageControl.currentPage == MJImageCount - 1) {        page = 0;    } else {        page = self.pageControl.currentPage + 1;    }        // 2.計算scrollView滾動的位置    CGFloat offsetX = page * self.scrollView.frame.size.width;    CGPoint offset = CGPointMake(offsetX, 0);    [self.scrollView setContentOffset:offset animated:YES];}#pragma mark - 代理方法/** *  當scrollView正在滾動就會調用 */- (void)scrollViewDidScroll:(UIScrollView *)scrollView{    // 根據scrollView的滾動位置決定pageControl顯示第幾頁    CGFloat scrollW = scrollView.frame.size.width;    int page = (scrollView.contentOffset.x + scrollW * 0.5) / scrollW;    self.pageControl.currentPage = page;}/** *  開始拖拽的時候調用 */- (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView{    // 停止定時器(一旦定時器停止了,就不能再使用)    [self removeTimer];}/** *  停止拖拽的時候調用 */- (void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate{    // 開啟定時器    [self addTimer];}@end

 

ios輪播圖片用法