效果图
实现代码
//.h 文件
@class LXBPageView;
@protocol LXBPageViewDataSource <NSObject>
///页面数量
- (NSInteger)subViewsNumberOfPageView:(LXBPageView *)pageView;
/// 某个位置的字视图
/// @param pageView 分页视图
/// @param index 索引
- (UIView *)subViewForPageView:(LXBPageView *)pageView
atIndex:(NSInteger)index;
@end
@protocol LXBPageViewDelegate <NSObject>
/// 分页视图中的滚动视图滚动
/// @param pageView 分页视图
/// @param scrollView scrollView
- (void)scrollViewInPageView:(LXBPageView *)pageView
didScroll:(UIScrollView *)scrollView;
/// 分页视图滚动到某个index
/// @param pageView 分页视图
/// @param index 索引
- (void)scrollViewInPageView:(LXBPageView *)pageView
didScrollToIndex:(NSInteger)index;
@end
@interface LXBPageView : UIView
///数据源
@property (nonatomic, weak) id <LXBPageViewDataSource> dataSource;
///代理
@property (nonatomic, weak) id <LXBPageViewDelegate> delegate;
@property (nonatomic, assign) NSInteger currentIndex;
- (void)reloadData;
///展示某个index
- (void)showSubViewWithIndex:(NSInteger)index;
@end
//.m 代码
@interface LXBPageView () <UIScrollViewDelegate>
@property (nonatomic, strong) UIScrollView *scrollView;
@end
@implementation LXBPageView
- (instancetype)initWithFrame:(CGRect)frame
{
if (self = [super initWithFrame:frame]) {
[self setUpUI];
[self setUpContraints];
}
return self;
}
- (void)setUpUI
{
[self addSubview:self.scrollView];
}
- (void)setUpContraints
{
[self.scrollView mas_makeConstraints:^(MASConstraintMaker *make) {
make.edges.mas_equalTo(UIEdgeInsetsZero);
}];
}
#pragma mark - public
- (void)reloadData
{
NSInteger numberOfSubViews = 0;
if (self.dataSource &&
[self.dataSource respondsToSelector:@selector(subViewsNumberOfPageView:)]) {
numberOfSubViews = [self.dataSource subViewsNumberOfPageView:self];
}
CGFloat width = CGRectGetWidth(self.scrollView.frame);
self.scrollView.contentSize = CGSizeMake(width * numberOfSubViews, 0);
[self showSubViewWithIndex:self.currentIndex];
}
- (void)showSubViewWithIndex:(NSInteger)index
{
CGFloat width = CGRectGetWidth(self.scrollView.frame);
[self.scrollView setContentOffset:CGPointMake(width * index, 0) animated:NO];
[self _showSubViewAtIndex:index];
if (self.delegate &&
[self.delegate respondsToSelector:@selector(scrollViewInPageView:didScrollToIndex:)]) {
[self.delegate scrollViewInPageView:self didScrollToIndex:index];
}
}
#pragma mark - UIScrollViewDelegate
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
if (self.delegate &&
[self.delegate respondsToSelector:@selector(scrollViewInPageView:didScroll:)]) {
[self.delegate scrollViewInPageView:self didScroll:scrollView];
}
}
- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView
{
CGFloat width = CGRectGetWidth(self.scrollView.frame);
NSInteger index = (scrollView.contentOffset.x + 0.5) / width;
[self _showSubViewAtIndex:index];
if (self.delegate &&
[self.delegate respondsToSelector:@selector(scrollViewInPageView:didScrollToIndex:)]) {
[self.delegate scrollViewInPageView:self didScrollToIndex:index];
}
}
#pragma mark - private
- (void)_showSubViewAtIndex:(NSInteger)index
{
UIView *view = [self.dataSource subViewForPageView:self atIndex:index];
if (![self.scrollView.subviews containsObject:view]) {
CGFloat width = CGRectGetWidth(self.scrollView.frame);
CGFloat height = CGRectGetHeight(self.scrollView.bounds);
view.frame = CGRectMake(index * width, 0, width, height);
[self.scrollView addSubview:view];
}
}
#pragma mark - lazy load
- (UIScrollView *)scrollView
{
if (!_scrollView) {
_scrollView = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 0, CGRectGetWidth(self.frame), CGRectGetHeight(self.frame))];
_scrollView.delegate = self;
_scrollView.pagingEnabled = YES;
_scrollView.showsHorizontalScrollIndicator = NO;
}
return _scrollView;
}
@end
使用方法
pod 'LXBPageView'
- (LXBPageView *)pageView
{
if (!_pageView) {
_pageView = [[LXBPageView alloc] init];
_pageView.dataSource = self;
_pageView.delegate = self;
}
return _pageView;
}
// 实现协议方法
#pragma mark - LBPageViewDelegate, LBPageViewDataSource
- (NSInteger)subViewsNumberOfPageView:(LXBPageView *)pageView
{
return self.contentArray.count;
}
- (UIView *)subViewForPageView:(LXBPageView *)pageView atIndex:(NSInteger)index
{
NSString *key = [NSString stringWithFormat:@"%ld",index];
LBContentView *view = [self.pageViewDic valueForKey:key];
if (view) {
return view;
} else {
view = [[LBContentView alloc] init];
view.backgroundColor = self.colorArray[index];
view.content = self.contentArray[index];
self.pageViewDic[key] = view;
return view;
}
}
- (void)scrollViewInPageView:(LXBPageView *)pageView didScroll:(UIScrollView *)scrollView
{
}
- (void)scrollViewInPageView:(LXBPageView *)pageView didScrollToIndex:(NSInteger)index
{
}