因为在项目中有用到滚动选择滑块切换控制器的控件，之前都是用的别人封装好的，但在使用中总感觉不舒服，对方的库写的也比较乱，所以博主一直想封装一个属于自己的滑动选择器，先看下效果图：
仔细察看的话会发现点击到中间位置时会有个小问题，会反方向滚动一段距离，该问题已修复，直接下载Demo查看即可
下面放下代码：
// // ScrollSliderView.h // 滚动导航条页面 // // Created by XXX on 16/6/13. // Copyright © 2016年 CodingFire. All rights reserved. // #import <UIKit/UIKit.h> @interface ScrollSliderView : UIView<UIScrollViewDelegate> #define VIEWWIDTH [UIScreen mainScreen].bounds.size.width #define VIEWHEIGHT [UIScreen mainScreen].bounds.size.height #define RAN_COLOR(CUS_RGB) [UIColor colorWithRed:((float)((CUS_RGB & 0xFF0000) >> 16))/255.0 green:((float)((CUS_RGB & 0xFF00) >> 8))/255.0 blue:((float)(CUS_RGB & 0xFF))/255.0 alpha:1.0f] /* * *初始化数据 */ -(id)initWithController:(UIViewController *)controller withTitleArray:(NSArray *)titleArray; /* *底部ScrollView */ @property (nonatomic,strong)UIScrollView *mainScrollView; /* *滑块ScrollView */ @property (nonatomic,strong)UIScrollView *sliderScrollView; /* *存放title的数组 */ @property (nonatomic,copy)NSArray *dataArray; /* *点击或滑动后选中的位置 */ @property (nonatomic, assign) NSInteger selectIndex; /* *所在的控制器 */ @property (nonatomic,weak)UIViewController *fatherController; @end
// // ScrollSliderView.m // 滚动导航条页面 // // Created by XXX on 16/6/13. // Copyright © 2016年 CodingFire. All rights reserved. // #import "ScrollSliderView.h" #import "SubViewController.h" #import "Cache.h" @implementation ScrollSliderView { Cache *cache; } /* *初始化底部ScrollView */ -(UIScrollView *)mainScrollView{ if (!_mainScrollView) { _mainScrollView = [[UIScrollView alloc]initWithFrame:CGRectMake(0, 100, VIEWWIDTH, VIEWHEIGHT-100)]; _mainScrollView.bounces = NO; _mainScrollView.showsVerticalScrollIndicator = NO; _mainScrollView.showsHorizontalScrollIndicator = NO; _mainScrollView.pagingEnabled = YES; _mainScrollView.backgroundColor = [UIColor lightGrayColor]; _mainScrollView.delegate = self; } return _mainScrollView; } /* *初始化self所有的控件 */ -(id)initWithController:(UIViewController *)controller withTitleArray:(NSArray *)titleArray { if (self = [super initWithFrame:[UIScreen mainScreen].bounds]) { cache = [[Cache alloc]init]; _dataArray = [NSArray arrayWithArray:titleArray]; _fatherController = controller; [self mainScrollView]; [self addSubview:_mainScrollView]; [self creatSliderScrollView:titleArray]; _mainScrollView.contentSize = CGSizeMake(titleArray.count*VIEWWIDTH, VIEWHEIGHT - 64 - 36); SubViewController *subVC = [SubViewController new]; subVC.index = 0; subVC.tilte = _dataArray[0]; subVC.view.frame = CGRectMake(0,0, VIEWWIDTH,_mainScrollView.frame.size.height); subVC.view.backgroundColor = [UIColor colorWithHue:(arc4random() % 256 / 256.0) saturation:(arc4random() % 128 / 256.0) + 0.5 brightness:(arc4random() % 128) + 0.5 alpha:1]; [_mainScrollView addSubview:subVC.view]; [controller addChildViewController:subVC]; [cache addCacheSelectIndex:0]; } return self; } /* *创建滑块 */ - (void)creatSliderScrollView:(NSArray *)array{ _sliderScrollView = [[UIScrollView alloc]initWithFrame:CGRectMake(0,64, VIEWWIDTH, 36)]; _sliderScrollView.backgroundColor = [UIColor whiteColor]; _sliderScrollView.bounces = NO; _sliderScrollView.showsHorizontalScrollIndicator = NO; _sliderScrollView.showsVerticalScrollIndicator = NO; [self addSubview:_sliderScrollView]; CGFloat spaceWidth = 6; CGFloat widthContentSize = 0; for (NSInteger i = 0; i < array.count; i++) { NSString *titleName = self.dataArray[i]; NSInteger strWidth = [self sizeforWidthWithString:titleName]; UIButton *btn = [UIButton buttonWithType:UIButtonTypeCustom]; UIView *sliderSign = [[UIView alloc]initWithFrame:CGRectMake(spaceWidth + widthContentSize,33,strWidth + 10,2)]; sliderSign.backgroundColor = RAN_COLOR(0xE43494); sliderSign.tag = 10000 + i; btn.frame = CGRectMake(spaceWidth+widthContentSize,2,strWidth + 10,32); [btn setTitle:titleName forState:UIControlStateNormal]; [btn setTitleColor:RAN_COLOR(0xE43494) forState:UIControlStateSelected]; [btn setTitleColor:[UIColor blackColor] forState:UIControlStateNormal]; btn.titleLabel.font = [UIFont systemFontOfSize:14]; [_sliderScrollView addSubview:btn]; [_sliderScrollView addSubview:sliderSign]; btn.tag = 20000 + i; if (i == 0) { btn.selected = YES; sliderSign.hidden = NO; }else{ sliderSign.hidden = YES; } widthContentSize = strWidth+10+spaceWidth+widthContentSize; [btn addTarget:self action:@selector(selectIndexTableViewAndCollectionView:) forControlEvents:UIControlEventTouchUpInside]; } self.sliderScrollView.contentSize = CGSizeMake(widthContentSize + 6, 36); } /* *计算title的长度 */ -(NSInteger)sizeforWidthWithString:(NSString *)str { NSDictionary *attribute = @{NSFontAttributeName: [UIFont systemFontOfSize:14]}; CGSize size = [str boundingRectWithSize:CGSizeMake(VIEWWIDTH - 10, 0) options: NSStringDrawingTruncatesLastVisibleLine | NSStringDrawingUsesLineFragmentOrigin | NSStringDrawingUsesFontLeading attributes:attribute context:nil].size; return size.width; } /* *点击滑块按钮响应事件 */ - (void)selectIndexTableViewAndCollectionView:(UIButton *)sender{ //按钮点击 先把所有的按钮都不选中 滑动条View隐藏 for (NSInteger i = 0; i < _dataArray.count; i++) { UIButton *btn = (UIButton *)[self viewWithTag:20000 + i]; UIView *sliderSign = (UIView *)[self viewWithTag:10000 + i]; sliderSign.hidden = YES; btn.selected = NO; } NSInteger index = sender.tag - 20000; self.selectIndex = index; //选中 为选中状态 sender.selected = YES; UIView *View = (UIView *)[self viewWithTag:index + 10000]; View.hidden = NO; UIButton *btnRight = [_sliderScrollView viewWithTag:sender.tag + 1]; UIButton *btnLeft = [_sliderScrollView viewWithTag:sender.tag - 1]; //分页 显示哪个控制器 _mainScrollView.contentOffset = CGPointMake(index*VIEWWIDTH,0); if ((sender.frame.origin.x + sender.frame.size.width) > VIEWWIDTH - 10){ if (sender.tag != (20000 + _dataArray.count - 1)) { [UIView animateWithDuration:0.3f animations:^{ self.sliderScrollView.contentOffset = CGPointMake(btnRight.frame.origin.x + btnRight.frame.size.width - VIEWWIDTH, 0); }]; } } else { [UIView animateWithDuration:0.3f animations:^{ self.sliderScrollView.contentOffset = CGPointMake(btnLeft.frame.origin.x, 0); }]; } if (![cache hasCacheIndex:_selectIndex]) { [self addSubController]; } } /* *创建未创建的滑块对应控制器 */ -(void)addSubController { SubViewController *subVC = [SubViewController new]; subVC.index = _selectIndex; subVC.tilte = _dataArray[_selectIndex]; [_mainScrollView addSubview:subVC.view]; subVC.view.frame = CGRectMake(_selectIndex*VIEWWIDTH,0, VIEWWIDTH,_mainScrollView.frame.size.height); subVC.view.backgroundColor = [UIColor colorWithHue:(arc4random() % 256 / 256.0) saturation:(arc4random() % 128 / 256.0) + 0.5 brightness:(arc4random() % 128) + 0.5 alpha:1]; [_mainScrollView addSubview:subVC.view]; [_fatherController addChildViewController:subVC]; } /* *UIScrollViewDelegate，控制滑动后变化 */ - (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView{ NSInteger index = scrollView.contentOffset.x/VIEWWIDTH; _selectIndex = index; for (NSInteger i = 0; i < _dataArray.count; i++) { UIButton *btn = (UIButton *)[self viewWithTag:20000 + i]; UIView *downSliderView = (UIView *)[self viewWithTag:10000 + i]; if (index == i) { downSliderView.hidden = NO; btn.selected = YES; }else{ downSliderView.hidden = YES; btn.selected = NO; } } UIButton *btnRight = [_sliderScrollView viewWithTag:index + 1 + 20000]; UIButton *btnCenter = [_sliderScrollView viewWithTag:index + 20000]; UIButton *btnLeft = [_sliderScrollView viewWithTag:index - 1 + 20000]; //分页 显示哪个控制器 _mainScrollView.contentOffset = CGPointMake(index * VIEWWIDTH,0); if ((btnCenter.frame.origin.x + btnCenter.frame.size.width) > VIEWWIDTH - 10){ if (btnCenter.tag != (20000 + _dataArray.count - 1)) { [UIView animateWithDuration:0.3f animations:^{ _sliderScrollView.contentOffset = CGPointMake(btnRight.frame.origin.x + btnRight.frame.size.width - VIEWWIDTH, 0); }]; } } else { [UIView animateWithDuration:0.3f animations:^{ _sliderScrollView.contentOffset = CGPointMake(btnLeft.frame.origin.x, 0); }]; } if (![cache hasCacheIndex:_selectIndex]) { [self addSubController]; } } /* // Only override drawRect: if you perform custom drawing. // An empty implementation adversely affects performance during animation. - (void)drawRect:(CGRect)rect { // Drawing code } */ @end
这里便是核心代码，另外还有个储存控制器的类，不再列出来了。这里博主写的比较传统，并没有进行高度的封装，很多属性没有单独留出来，也怪博主懒，也是给大家提供一个发挥的空间，如果有什么疑问和不合理的地方，欢迎留言，代码下载地址请看：https://github.com/codeliu6572/ScrollSelector
