非转场动画,动画效果

#import <UIKit/UIKit.h>

@interface UIView (Debris)

/*
 pop返回碎片动画
 @property  调用示例
 
 [[UIApplication sharedApplication].keyWindow addSubview:self.view];
 [self.view fragmenttationAnimation];
 [self.navigationController popViewControllerAnimated:NO];
 
 */
- (void)fragmenttationAnimation;

@end

#import "UIView+Debris.h"

@implementation UIView (Debris)

- (void)fragmenttationAnimation {
    // 先截图
    UIView *snapView = [self snapshotViewAfterScreenUpdates:YES];
    // 隐藏容器中的子控件
    for (UIView *view in self.subviews) {
        view.hidden = YES;
    }
    
    // 保存x坐标的数组
    NSMutableArray *xArray = [[NSMutableArray alloc] init];
    // 保存y坐标
    NSMutableArray *yArray = [[NSMutableArray alloc] init];
    
    for (NSInteger i = 0; i < self.bounds.size.width; i = i + 10) {
        @autoreleasepool{
            [xArray addObject:@(i)];
        }
    }
    for (NSInteger i = 0; i < self.bounds.size.height; i = i + 10) {
        @autoreleasepool{
            [yArray addObject:@(i)];
        }
    }
    
    //这个保存所有的碎片
    NSMutableArray *snapshots = [[NSMutableArray alloc] init];
    for (NSNumber *x in xArray) {
        for (NSNumber *y in yArray) {
            @autoreleasepool{
                CGRect snapshotRegion = CGRectMake([x doubleValue], [y doubleValue], 10, 10);
                // resizableSnapshotViewFromRect 这个方法就是根据frame 去截图
                UIView *snapshot      = [snapView resizableSnapshotViewFromRect:snapshotRegion afterScreenUpdates:NO withCapInsets:UIEdgeInsetsZero];
                snapshot.frame        = snapshotRegion;
                [self addSubview:snapshot];
                [snapshots         addObject:snapshot];
            }
        }
    }
    
    [UIView animateWithDuration:1.5
                          delay:0
                        options:UIViewAnimationOptionCurveLinear
                     animations:^{
        for (UIView *view in snapshots) {
            @autoreleasepool{
                view.frame = CGRectOffset(view.frame, [self randomRange:200 offset:-100], [self randomRange:200 offset:self.frame.size.height/2]);
                self.alpha = 0.1;
            }
        }
    }completion:^(BOOL finished) {
        for (UIView *view in snapshots) {
            [view removeFromSuperview];
        }
        [self removeFromSuperview];
    }];
}

- (CGFloat)randomRange:(NSInteger)range offset:(NSInteger)offset {
    return (CGFloat)(arc4random()%range + offset);
}

@end

#define Main_Width [UIScreen mainScreen].bounds.size.width
#define Main_Height [UIScreen mainScreen].bounds.size.height

#import "ViewController.h"
#import "SecondViewController.h"

@interface ViewController ()

@property (nonatomic, strong) UIImageView * bgImageView;

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    
    self.title = @"主视图";
    [self.view addSubview:self.bgImageView];
}

- (UIImageView *)bgImageView {
    if (!_bgImageView) {
        _bgImageView = [[UIImageView alloc]init];
        _bgImageView.image = [UIImage imageNamed:@"m8.jpg"];
        _bgImageView.center = CGPointMake(Main_Width/2, Main_Height/2);
        _bgImageView.bounds = CGRectMake(0, 0, 300, 300);
        _bgImageView.contentMode = UIViewContentModeScaleAspectFill;
        _bgImageView.userInteractionEnabled = YES;
        UITapGestureRecognizer * tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(pushNextVC)];
        [_bgImageView addGestureRecognizer:tap];
    }
    return _bgImageView;
}

- (void)pushNextVC {
    SecondViewController * vc = [[SecondViewController alloc]init];
    [self.navigationController pushViewController:vc animated:YES];
}

@end

#define Main_Width [UIScreen mainScreen].bounds.size.width
#define Main_Height [UIScreen mainScreen].bounds.size.height

#import "SecondViewController.h"
#import "UIView+Debris.h"

@interface SecondViewController ()

@property (nonatomic, strong) UIImageView * debrisAnimationImageView;

@end

@implementation SecondViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    
    self.title = @"碎片动画返回效果";
    [self.view addSubview:self.debrisAnimationImageView];
    self.automaticallyAdjustsScrollViewInsets = NO;
}

- (UIImageView *)debrisAnimationImageView{
    if (!_debrisAnimationImageView) {
        _debrisAnimationImageView = [[UIImageView alloc]init];
        _debrisAnimationImageView.frame = CGRectMake(0, 64, Main_Width, Main_Height-64);
        _debrisAnimationImageView.contentMode = UIViewContentModeScaleAspectFill;
        _debrisAnimationImageView.image = [UIImage imageNamed:@"we.jpeg"];
        _debrisAnimationImageView.userInteractionEnabled = YES;
        UITapGestureRecognizer * tap = [[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(didSelectDebrisImageView)];
        [_debrisAnimationImageView addGestureRecognizer:tap];
    }
    return _debrisAnimationImageView;
}

- (void)didSelectDebrisImageView {
    [[UIApplication sharedApplication].keyWindow addSubview:self.view];
    [self.view fragmenttationAnimation];
    [self.navigationController popViewControllerAnimated:NO];
}

@end