bhaveshdhaduk/ltinfinitescrollview

An infinite scrollview allowing easily applying animation

Demo

1. You can apply animation to each view during the scroll:

2. The iOS 9 task switcher animation can be implemented in ten minutes with the support of this lib:

3. The fancy menu can also be implemented easily:

Usage

Create the scroll view by:

self.scrollView = [[LTInfiniteScrollView alloc]initWithFrame:CGRectMake(0, 0, CGRectGetWidth(self.view.bounds), 200)];
[self.view addSubview:self.scrollView];
self.scrollView.dataSource = self;
[self.scrollView reloadData];

Then implement LTInfiniteScrollViewDataSource protocol:

@protocol LTInfiniteScrollViewDataSource <NSObject>
- (UIView *)viewAtIndex:(NSInteger)index reusingView:(UIView *)view;
- (NSInteger)numberOfViews;
- (NSInteger)numberOfVisibleViews;
@end

Sample code:

- (NSInteger)numberOfViews
{
    // you can set it to a very big number to mimic the infinite behavior, no performance issue here
    return 9999; 
}

- (NSInteger)numberOfVisibleViews
{
    return 5;
}

- (UIView *)viewAtIndex:(NSInteger)index reusingView:(UIView *)view;
{
    if (view) {
        ((UILabel*)view).text = [NSString stringWithFormat:@"%ld", index];
        return view;
    }
    
    UILabel *aView = [[UILabel alloc]initWithFrame:CGRectMake(0, 0, 64, 64)];
    aView.backgroundColor = [UIColor blackColor];
    aView.layer.cornerRadius = 32;
    aView.layer.masksToBounds = YES;
    aView.backgroundColor = [UIColor colorWithRed:0/255.0 green:175/255.0 blue:240/255.0 alpha:1];
    aView.textColor = [UIColor whiteColor];
    aView.textAlignment = NSTextAlignmentCenter;
    aView.text = [NSString stringWithFormat:@"%ld", index];
    return aView;
}

LTInfinitedScrollView interface:

@interface LTInfiniteScrollView : UIView
@property (nonatomic) NSInteger currentIndex;
@property (nonatomic,weak) id<LTInfiniteScrollViewDataSource> dataSource;
@property (nonatomic,weak) id<LTInfiniteScrollViewDelegate> delegate;
@property (nonatomic) BOOL scrollEnabled;
@property (nonatomic) BOOL pagingEnabled;
@property (nonatomic) NSInteger maxScrollDistance; 

- (void)reloadData;
- (void)scrollToIndex:(NSInteger)index animated:(BOOL)animated;
- (UIView *)viewAtIndex:(NSInteger)index;
- (NSArray *)allViews;
@end

If you want to apply any animation during scrolling, implement LTInfiniteScrollViewDelegate protocol:

@protocol LTInfiniteScrollViewDelegate <NSObject>
- (void)updateView:(UIView *)view withProgress:(CGFloat)progress scrollDirection:(ScrollDirection)direction;
@end

The value of progress dependends on the position of that view, if there are 5 visible views, the value will be ranged from -2 to 2:

|                  |
|-2  -1   0   1   2|
|                  |

You can clone the project and investigate the example for details.