iOS菜单滚动联动内容区域功能实现

平时开发APP中关于此功能还是比较经常碰到，本实例借用三个开源的插件，并对其中一个进行修改调整实现出想要的效果；本文重点介绍修改的内容跟三个插件的运用，这三个插件还可以各自扩展到其它项目的运用；

效果图：

本实例实现的效果：顶部的滚动菜单显示出所有的类型，每个类型都对应一种展示，可以在顶部的菜单进行滚动，内容区域也会跟着改变，或者是内容区域左右滑动，则顶部的滚动菜单也会跟着更改，顶部菜单的最右边有一个展示更多菜单的效果，用于弹出一个带箭头的窗；(源代码下载)

带箭头的弹出视图插件 ：https://github.com/xiekw2010/DXPopover

内容区域滑动插件：https://github.com/nicklockwood/iCarousel

及Codint.Net开源项目中的XTSegmentControl菜单滚动效果，此实例对它进行的修改

1：插件及页面的初始化

#import "ViewController.h"
#import "oldChildVewController.h"
#import "ChildViewController.h"
#import "newChildVewController.h"
#import "XTSegmentControl.h"
#import "iCarousel.h"
#import "Masonry.h"
#import "menuCollectionViewCell.h"
#import "DXPopover.h"

#define kScreen_Height [UIScreen mainScreen].bounds.size.height
#define kScreen_Width [UIScreen mainScreen].bounds.size.width
#define kMySegmentControl_Height 44.0

@interface ViewController ()<UICollectionViewDataSource, UICollectionViewDelegate,iCarouselDataSource, iCarouselDelegate>
@property (strong, nonatomic) XTSegmentControl *mySegmentControl;
@property (strong, nonatomic) NSArray *titlesArray;
@property (strong, nonatomic) iCarousel *myCarousel;
@property(assign,nonatomic)NSInteger curSelectIndex;
@property (nonatomic, strong) DXPopover *popover;
@property(assign,nonatomic)CGFloat popoverWidth;
@property (strong, nonatomic) UICollectionView *myCollectionView;
@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    self.view.backgroundColor=[UIColor whiteColor];

    //初始化一个popover 用于弹窗效果的展示
    self.popover = [DXPopover new];
    _popoverWidth = kScreen_Width-;

    __weak typeof(self) weakSelf = self;
    CGRect frame=self.view.bounds;

    //内容区滚动效果插件
    self.myCarousel = ({
        iCarousel *icarousel = [[iCarousel alloc] initWithFrame:frame];
        icarousel.dataSource = self;
        icarousel.delegate = self;
        icarousel.decelerationRate = 1.0;
        icarousel.scrollSpeed = 1.0;
        icarousel.type = iCarouselTypeLinear;
        icarousel.pagingEnabled = YES;
        icarousel.clipsToBounds = YES;
        icarousel.bounceDistance = 0.2;
        [self.view addSubview:icarousel];
        [icarousel mas_makeConstraints:^(MASConstraintMaker *make) {
            make.edges.equalTo(self.view).insets(UIEdgeInsetsMake(, , , ));
        }];
        icarousel;
    });

    //添加滑块
    __weak typeof(_myCarousel) weakCarousel = _myCarousel;
    self.mySegmentControl = [[XTSegmentControl alloc] initWithFrame:CGRectMake(, , kScreen_Width, ) Items:self.titlesArray showRightButton:YES selectedBlock:^(NSInteger index) {
        weakSelf.curSelectIndex=index;
        weakCarousel.currentItemIndex=index;
        [weakSelf.myCollectionView reloadData];
    }];
    //当有右边键时 其响应的事件
    self.mySegmentControl.rightButtonBlock= ^(CGRect rightButtomRect)
    {
        //弹出插件的运用
        [weakSelf updateMyViewFrame];
        CGPoint startPoint =
        CGPointMake(CGRectGetMidX(rightButtomRect), CGRectGetMaxY(rightButtomRect) + );
        [weakSelf.popover showAtPoint:startPoint
                   popoverPostion:DXPopoverPositionDown
                  withContentView:weakSelf.myCollectionView
                           inView:weakSelf.view];
    };
    [self.view addSubview:self.mySegmentControl];

    //用于展示弹出效果里面的列表
    if (!_myCollectionView) {
        UICollectionViewFlowLayout *layout = [[UICollectionViewFlowLayout alloc] init];
        self.myCollectionView = [[UICollectionView alloc] initWithFrame:CGRectMake(,,kScreen_Width-, ) collectionViewLayout:layout];
        self.myCollectionView.backgroundColor=[UIColor whiteColor];
        self.myCollectionView.showsHorizontalScrollIndicator=NO;
        self.myCollectionView.showsVerticalScrollIndicator=NO;
        [self.myCollectionView registerClass:[menuCollectionViewCell class] forCellWithReuseIdentifier:NSStringFromClass([menuCollectionViewCell class])];
        self.myCollectionView.dataSource = self;
        self.myCollectionView.delegate = self;
    }
}

其中XTSegmentControl为顶部菜单的创建，其中showRightButton是为了扩展是否显示右边更多菜单的事件，并把事件的响应Block到页面进行实现，此事例就是响应弹出窗的效果展现，iCarousel为内容区域的滑动效果，DXPopover弹出窗的效果，UICollectionView则用于弹出窗里面的菜单列表

//popver一些属性的设置
-(void)updateMyViewFrame
{
    CGRect tableViewFrame = self.myCollectionView.frame;
    tableViewFrame.size.width = _popoverWidth;
    self.myCollectionView.frame = tableViewFrame;
    self.popover.contentInset = UIEdgeInsetsZero;
    self.popover.backgroundColor = [UIColor whiteColor];
}

#pragma mark - Getter/Setter
- (NSArray*)titlesArray
{
    if (nil == _titlesArray) {
            _titlesArray = @[@"全部", @"互动", @"开源控件", @"文档", @"代码", @"高尔夫",@"主题",@"软件",@"股票"];
    }
    return _titlesArray;
}

2插件iCarouselDataSource, iCarouselDelegate代码实现

#pragma mark iCarousel M
- (NSUInteger)numberOfItemsInCarousel:(iCarousel *)carousel{
    return [self.titlesArray count];
}

//滚动时内容视图的加载
- (UIView *)carousel:(iCarousel *)carousel viewForItemAtIndex:(NSUInteger)index reusingView:(UIView *)view{
    [_mySegmentControl setScrollOffset:index];
    UIViewController *childContrll=[[ChildViewController alloc]init];
    UIView *my=childContrll.view;
    switch (index) {
        case :
        {
            my.backgroundColor=[UIColor blackColor];
            break;
        }
        case :
        {
            my.backgroundColor=[UIColor redColor];
            break;
        }
        default:
            childContrll=[[newChildVewController alloc]init];
            break;
    }
    return childContrll.view;
}

//滚动时 下划线的位置更新
- (void)carouselDidScroll:(iCarousel *)carousel{
    if (_mySegmentControl) {
        [_mySegmentControl moveIndexWithProgress];
    }
}

//更新滚动其它两个控件的位置
- (void)carouselCurrentItemIndexDidChange:(iCarousel *)carousel{
    self.curSelectIndex=carousel.currentItemIndex;
    [self.myCollectionView reloadData];
    if (_mySegmentControl) {
        _mySegmentControl.currentIndex = carousel.currentItemIndex;
    }
}

注意：内容区域的视图加载，及其滑动所响应的事件处理，原来的XTSegmentControl对于菜单字数不同时下划线会出现一些异常，本实例对它进行修改了；

3：列表UICollectionViewDataSource, UICollectionViewDelegate功能的实现

- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section{
    return self.titlesArray.count;
}

- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath{
    menuCollectionViewCell *ccell = [collectionView dequeueReusableCellWithReuseIdentifier:NSStringFromClass([menuCollectionViewCell class]) forIndexPath:indexPath];
    NSString *model=[self.titlesArray objectAtIndex:indexPath.row];
    ccell.curMenuModel=model;
    if (self.curSelectIndex==indexPath.row) {
        ccell.backgroundColor=[UIColor blueColor];
    }
    else
    {
        ccell.backgroundColor=[UIColor whiteColor];
    }
    return ccell;
}

- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath{
    return CGSizeMake((kScreen_Width-)/, );
}
- (UIEdgeInsets)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout insetForSectionAtIndex:(NSInteger)section{
    return UIEdgeInsetsZero;
}
- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout minimumLineSpacingForSectionAtIndex:(NSInteger)section{
    return ;
}
- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout minimumInteritemSpacingForSectionAtIndex:(NSInteger)section{
    return ;
}

- (void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath{
    self.curSelectIndex=indexPath.row;
    //两个滚动的位置更新
    _myCarousel.currentItemIndex=self.curSelectIndex;
    [_mySegmentControl selectIndex:self.curSelectIndex];
    //隐藏弹出窗
    [self.popover dismiss];
}

注意：主要是在实现点击时滚动位置跟内容的区域要进行调整，并把弹出窗进行收缩的操作；

4：XTSegmentControl下划线调整

- (void)moveIndexWithProgress
{
    CGRect origionRect = [_itemFrames[_currentIndex] CGRectValue];

    CGRect origionLineRect = CGRectMake(CGRectGetMinX(origionRect) + XTSegmentControlHspace, CGRectGetHeight(origionRect) - XTSegmentControlLineHeight, CGRectGetWidth(origionRect) -  * XTSegmentControlHspace, XTSegmentControlLineHeight);

    //增加下划线滚动的效果
    [UIView animateWithDuration:0.5 animations:^{
        _lineView.frame = origionLineRect;
    } completion:^(BOOL finished) {

    }];

}

5：扩展XTSegmentControl没有右边更多菜单的效果

    self.mySegmentControl = [[XTSegmentControl alloc] initWithFrame:CGRectMake(, , kScreen_Width, ) Items:self.titlesArray showRightButton:NO selectedBlock:^(NSInteger index) {
        weakSelf.curSelectIndex=index;
        weakCarousel.currentItemIndex=index;
        [weakSelf.myCollectionView reloadData];
    }];

效果图：

6:补充关于popover这个插件的如果有模态时，它会出现整个屏幕，如果不想要这种效果，可以自个设置一个背景视图效果，把popover模态效果关掉（self.popover.maskType=DXPopoverMaskTypeNone; //设置默认是否有模态）；下面是写的一个实例：

- (void)updateTableViewFrame {
    CGRect tableViewFrame = self.tableView.frame;
    tableViewFrame.size.width = _popoverWidth;
    self.tableView.frame = tableViewFrame;
    self.popover.contentInset = UIEdgeInsetsZero;
    self.popover.maskType=DXPopoverMaskTypeNone; //设置默认是否有模态
    self.popover.backgroundColor = [UIColor whiteColor];
}

- (void)showPopover {
    [self updateTableViewFrame];

    [self changeShowing];

    CGPoint startPoint =
        CGPointMake(CGRectGetMidX(self.btn.frame), CGRectGetMaxY(self.btn.frame) + );
    [self.popover showAtPoint:startPoint
               popoverPostion:DXPopoverPositionDown
              withContentView:self.tableView
                       inView:self.tabBarController.view];

    __weak typeof(self) weakSelf = self;
    self.popover.didDismissHandler = ^{
        [weakSelf bounceTargetView:weakSelf.btn];
    };
}

//自行增加一个背影层
- (UIView *)myTapBackgroundView{
    if (!_myTapBackgroundView) {
        _myTapBackgroundView = ({
            UIView *view = [[UIView alloc] initWithFrame:CGRectMake(, , [[UIScreen mainScreen] bounds].size.width, [[UIScreen mainScreen] bounds].size.height-)];
            view.backgroundColor = [UIColor clearColor];
            UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(changeShowing)];
            [view addGestureRecognizer:tap];
            view;
        });
    }
    return _myTapBackgroundView;
}

- (void)changeShowing{

    if (self.isShowing) {//隐藏
        [UIView animateWithDuration:0.3 animations:^{
            self.myTapBackgroundView.backgroundColor = [UIColor colorWithWhite: alpha:];
        } completion:^(BOOL finished) {
            [self.popover dismiss];
            [self.myTapBackgroundView removeFromSuperview];
            self.isShowing = NO;
        }];
    }else{//显示
        [self.view addSubview:self.myTapBackgroundView];
        [UIView animateWithDuration:0.3 animations:^{
            self.myTapBackgroundView.backgroundColor = [UIColor colorWithWhite: alpha:0.2];
        } completion:^(BOOL finished) {
            self.isShowing = YES;
        }];
    }
}