pageViewController实现多视图（控制器）滑动切换
先看一下效果动画
类似的界面做过不少，，在几个APP中都有用到过，，再次之前不了解uipageViewController 曾经的思路有两个现在想想都觉得繁琐，，
之前的思路1：使用嵌套，collectionview嵌套，每个item中添加内容
之前的思路2：使用scrollview 在上面创建一个一个的controller 实现左右滑动
这两个思路无疑是可以实现的 并且可以实现每个页面的重用，，滑动等都可以 唯独一点不好就是当停留在第一页的时候 点击标题栏第五页，，那么平移的过程就是第一页到第五页，，所有的页面从屏幕快速闪过，，并且看到现在很多APP都是这样的。。在此之前我是用的思路2，，为了避免跨页面切换出现的中间几个页面闪过的过程，，直接把平移动画关闭了。。直到使用了uipageViewController，，赶紧把项目中的给换掉了
代码不多150行以内
#import "ViewController.h"/// 当前controller
#import "MyViewController.h" /// 复用的controller 适用于每个控制器布局相同的情况下，，布局不同就创建不同的controller添加进来
#import "TitleCollectionViewCell.h"/// 标题栏使用的collectionviewcell
@interface ViewController ()<UIPageViewControllerDelegate,UIPageViewControllerDataSource,UICollectionViewDelegate,UICollectionViewDataSource>{
//// 记录当前页 当前标题位置
NSInteger ld_currentIndex;
}
@property (nonatomic, strong) UIPageViewController *pageViewController;
@property (nonatomic, strong) NSMutableArray *controllersArr;/// 控制器数组
@property (nonatomic, strong) NSMutableArray *titleArray; /// 标题数组
@property (nonatomic, strong) UICollectionView *titleCollectionView; /// 标题collectionview
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
self.view.backgroundColor = [UIColor whiteColor];
self.navigationController.navigationBar.translucent = NO;
self.controllersArr = [NSMutableArray array];
self.titleArray = [NSMutableArray array];
//// 如果controller布局相同则循环创建MyViewController 添加进数组，，如果controller 布局不同 那就创建多个不同controller依次添加数组
for (int i = 0; i < 10; i++) {
MyViewController *con = [[MyViewController alloc]init];
[self.controllersArr addObject:con];
NSString *str = [NSString stringWithFormat:@"第 %d 页", i+1];
con.titlestring = str;
[self.titleArray addObject:str];
}
[self createCollectionView];
[self createPageViewController];
[self setTheFirstPage];
}
/// 创建标题collectionview
- (void)createCollectionView{
UICollectionViewFlowLayout *lay = [[UICollectionViewFlowLayout alloc] init];
lay.itemSize = CGSizeMake(60, 30);
lay.minimumLineSpacing = 0;
lay.minimumInteritemSpacing = 0;
lay.scrollDirection = UICollectionViewScrollDirectionHorizontal;
self.titleCollectionView = [[UICollectionView alloc] initWithFrame:CGRectMake(0, 34, 375, 30) collectionViewLayout:lay];
self.titleCollectionView.showsHorizontalScrollIndicator = NO;
self.titleCollectionView.backgroundColor = [UIColor whiteColor];
self.titleCollectionView.delegate = self;
self.titleCollectionView.dataSource = self;
[self.titleCollectionView registerClass:[TitleCollectionViewCell class] forCellWithReuseIdentifier:@"titleReuse"];
[self.navigationController.view addSubview:self.titleCollectionView];
}
//// 标题collectionview的协议方法
- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section{
return self.titleArray.count;
}
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath {
TitleCollectionViewCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"titleReuse" forIndexPath:indexPath];
cell.titleLabel.text = self.titleArray[indexPath.row];
if (indexPath.row == ld_currentIndex) {
cell.titleLabel.textColor = [UIColor orangeColor];
}else{
cell.titleLabel.textColor = [UIColor blackColor];
}
return cell;
}
//// 点击标题左右切换视图控制器------------再也不用看到好几个中间页面从屏幕快速闪过了------
- (void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath{
UIViewController *vc = [self.controllersArr objectAtIndex:indexPath.row];
if (indexPath.row > ld_currentIndex) {
[self.pageViewController setViewControllers:@[vc] direction:UIPageViewControllerNavigationDirectionForward animated:YES completion:^(BOOL finished) {
}];
} else {
[self.pageViewController setViewControllers:@[vc] direction:UIPageViewControllerNavigationDirectionReverse animated:YES completion:^(BOOL finished) {
}];
}
ld_currentIndex = indexPath.row;
NSIndexPath *path = [NSIndexPath indexPathForRow:ld_currentIndex inSection:0];
[self.titleCollectionView scrollToItemAtIndexPath:path atScrollPosition:UICollectionViewScrollPositionCenteredHorizontally animated:YES];
[self.titleCollectionView reloadData];
}
/// 创建pageViewController
- (void)createPageViewController {
NSDictionary *option = [NSDictionary dictionaryWithObject:[NSNumber numberWithInteger:0] forKey:UIPageViewControllerOptionInterPageSpacingKey];
_pageViewController = [[UIPageViewController alloc]initWithTransitionStyle:UIPageViewControllerTransitionStyleScroll navigationOrientation:UIPageViewControllerNavigationOrientationHorizontal options:option];
_pageViewController.delegate = self;
_pageViewController.dataSource = self;
[self addChildViewController:_pageViewController];
[self.view addSubview:_pageViewController.view];
}
/// 展示上一页
- (nullable UIViewController *)pageViewController:(UIPageViewController *)pageViewController viewControllerBeforeViewController:(UIViewController *)viewController {
NSInteger index = [self.controllersArr indexOfObject:viewController];
if (index == 0 || (index == NSNotFound)) {
return nil;
}
index--;
return [self.controllersArr objectAtIndex:index];
}
/// 展示下一页
- (nullable UIViewController *)pageViewController:(UIPageViewController *)pageViewController viewControllerAfterViewController:(UIViewController *)viewController {
NSInteger index = [self.controllersArr indexOfObject:viewController];
if (index == self.controllersArr.count - 1 || (index == NSNotFound)) {
return nil;
}
index++;
return [self.controllersArr objectAtIndex:index];
}
/// 将要滑动切换的时候
- (void)pageViewController:(UIPageViewController *)pageViewController willTransitionToViewControllers:(NSArray<UIViewController *> *)pendingViewControllers {
UIViewController *nextVC = [pendingViewControllers firstObject];
NSInteger index = [self.controllersArr indexOfObject:nextVC];
ld_currentIndex = index;
}
/// 滑动结束后
- (void)pageViewController:(UIPageViewController *)pageViewController didFinishAnimating:(BOOL)finished previousViewControllers:(NSArray<UIViewController *> *)previousViewControllers transitionCompleted:(BOOL)completed {
if (completed) {
NSIndexPath *path = [NSIndexPath indexPathForRow:ld_currentIndex inSection:0];
[self.titleCollectionView scrollToItemAtIndexPath:path atScrollPosition:UICollectionViewScrollPositionCenteredHorizontally animated:YES];
[self.titleCollectionView reloadData];
NSLog(@">>>>>>>>> %ld", (long)ld_currentIndex);
}
}
/// 设置默认显示的是哪个页面（controller）
- (void)setTheFirstPage{
UIViewController *vc = [self.controllersArr objectAtIndex:ld_currentIndex];
[self.pageViewController setViewControllers:@[vc] direction:UIPageViewControllerNavigationDirectionReverse animated:YES completion:nil];
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
TitleCollectionViewCell
@implementation TitleCollectionViewCell
- (instancetype)initWithFrame:(CGRect)frame{
self = [super initWithFrame:frame];
if (self) {
[self createView];
}
return self;
}
- (void)createView{
self.titleLabel = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, self.contentView.frame.size.width, self.contentView.frame.size.height)];
[self.contentView addSubview:self.titleLabel];
self.titleLabel.font = [UIFont systemFontOfSize:14];
}
@end