UIScrollView视差效果动画

UIScrollView视差效果动画

效果

源码

https://github.com/YouXianMing/Animations

//
//  ScrollImageViewController.m
//  Animations
//
//  Created by YouXianMing on 15/11/24.
//  Copyright © 2015年 YouXianMing. All rights reserved.
//

#import "ScrollImageViewController.h"
#import "MoreInfoView.h"
#import "UIView+SetRect.h"
#import "Math.h"

static int type    = ;
static int viewTag = 0x11;

@interface ScrollImageViewController () <UIScrollViewDelegate>

@property (nonatomic, strong) NSArray       *picturesArray;
@property (nonatomic, strong) UIScrollView  *scrollView;
@property (nonatomic, strong) Math          *onceLinearEquation;

@end

@implementation ScrollImageViewController

- (void)viewDidLoad {

    [super viewDidLoad];
}

- (void)setup {

    [super setup];

    MATHPoint pointA;
    MATHPoint pointB;

    // Type.
    if (type %  == ) {

        pointA = MATHPointMake(, -);
        pointB = MATHPointMake(self.view.width,  - );

    } else if (type %  == ) {

        pointA = MATHPointMake(, -);
        pointB = MATHPointMake(self.view.width,  - );

    } else if (type %  == ) {

        pointA = MATHPointMake(, -);
        pointB = MATHPointMake(self.view.width,  + );

    } else if (type %  == ) {

        pointA = MATHPointMake(, -);
        pointB = MATHPointMake(self.view.width,  + );
    }

    self.onceLinearEquation = [Math mathOnceLinearEquationWithPointA:pointA PointB:pointB];

    type++;

    // Init pictures data.
    self.picturesArray = @[[UIImage imageNamed:@""],
                           [UIImage imageNamed:@""],
                           [UIImage imageNamed:@""],
                           [UIImage imageNamed:@""],
                           [UIImage imageNamed:@""]];

    // Init scrollView.
    CGFloat height = self.view.height;
    CGFloat width  = self.view.width;

    _scrollView = [[UIScrollView alloc] initWithFrame:self.view.bounds];
    _scrollView.delegate                       = self;
    _scrollView.pagingEnabled                  = YES;
    _scrollView.backgroundColor                = [UIColor blackColor];
    _scrollView.showsHorizontalScrollIndicator = NO;
    _scrollView.bounces                        = NO;
    _scrollView.contentSize                    = CGSizeMake(self.picturesArray.count * width, height);
    [self.view addSubview:_scrollView];

    // Init moreInfoViews.
    for (int i = ; i < self.picturesArray.count; i++) {

        MoreInfoView *show   = [[MoreInfoView alloc] initWithFrame:CGRectMake(i * width, , width, height)];
        show.imageView.image = self.picturesArray[i];
        show.tag             = viewTag + i;

        [_scrollView addSubview:show];
    }

    [self bringTitleViewToFront];
}

- (void)scrollViewDidScroll:(UIScrollView *)scrollView {

    CGFloat X = scrollView.contentOffset.x;

    for (int i = ; i < self.picturesArray.count; i++) {

        MoreInfoView *show = [scrollView viewWithTag:viewTag + i];
        show.imageView.x   = _onceLinearEquation.k * (X - i * self.view.width) + _onceLinearEquation.b;
    }
}

@end

细节