iOS：模态之蒙版设置

MZBasePresentFadeAnimationVC.h

NS_ASSUME_NONNULL_BEGIN

@interface MZBasePresentFadeAnimationVC : UIViewController

///蒙版
@property (nonatomic, strong) UIView *backgroundView;
///点击蒙版是否dismiss掉当前控制器, 默认为YES
@property (nonatomic, assign) BOOL outsideTapDismissEnable;
///dismiss结束后的回调
@property (nonatomic, copy) void (^dismissComplete)(void);

@end

NS_ASSUME_NONNULL_END

MZBasePresentFadeAnimationVC.m

#import "MZBasePresentFadeAnimationVC.h"

//MARK: - MZBaseAnimation
@interface MZBaseAnimation : NSObject

/// present or dismiss
@property (nonatomic, assign, readonly) BOOL isPresenting;

+ (instancetype)alertAnimationIsPresenting:(BOOL)isPresenting;

@end

//MARK: - MZBasePresentFadeAnimationVC
@interface MZBasePresentFadeAnimationVC ()

@property (nonatomic, weak) UITapGestureRecognizer *singleTap;

@end

@implementation MZBasePresentFadeAnimationVC

- (instancetype)init {
    if (self = [super init]) {
        [self configController];
    }
    return self;
}

- (instancetype)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil {
    if (self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]) {
        [self configController];
    }
    return self;
}

- (void)viewDidLoad {
    [super viewDidLoad];

    [self addBackgroundView];
    [self addSingleTapGesture];
}

- (void)configController {
    self.providesPresentationContextTransitionStyle = YES;
    self.definesPresentationContext = YES;
    self.modalPresentationStyle = UIModalPresentationCustom;
    self.outsideTapDismissEnable = YES;
    self.transitioningDelegate = self;
}

- (void)addBackgroundView {
    if (self.backgroundView == nil) {
        UIView *backgroundView = [[UIView alloc] initWithFrame:UIScreen.mainScreen.bounds];
        backgroundView.backgroundColor = [[UIColor blackColor] colorWithAlphaComponent:0.4];
        self.backgroundView = backgroundView;
    }
    self.backgroundView.translatesAutoresizingMaskIntoConstraints = NO;
    [self.view insertSubview:self.backgroundView atIndex:0];
}

- (void)addSingleTapGesture {
    self.view.userInteractionEnabled = YES;
    self.backgroundView.userInteractionEnabled = YES;

    UITapGestureRecognizer *singleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(onTap:)];
    singleTap.enabled = self.outsideTapDismissEnable;

    [self.backgroundView addGestureRecognizer:singleTap];
    self.singleTap = singleTap;
}

- (void)onTap:(UITapGestureRecognizer *)tapGesture {
    [self dismissViewControllerAnimated:YES];
}

- (void)dismissViewControllerAnimated:(BOOL)animated {
    [self dismissViewControllerAnimated:YES completion:self.dismissComplete];
}

@end


@implementation MZBasePresentFadeAnimationVC (TransitionAnimate)

- (id)animationControllerForPresentedController:(UIViewController *)presented presentingController:(UIViewController *)presenting sourceController:(UIViewController *)source {
    return [MZBaseAnimation alertAnimationIsPresenting:YES];
}

- (id)animationControllerForDismissedController:(UIViewController *)dismissed {
    return [MZBaseAnimation alertAnimationIsPresenting:NO];
}

@end



//MARK: - MZBaseAnimation
@interface MZBaseAnimation ()
@property (nonatomic, assign) BOOL isPresenting;
@end

@implementation MZBaseAnimation

- (instancetype)initWithIsPresenting:(BOOL)isPresenting {
    if (self = [super init]) {
        self.isPresenting = isPresenting;
    }
    return self;
}

+ (instancetype)alertAnimationIsPresenting:(BOOL)isPresenting {
    return [[self alloc]initWithIsPresenting:isPresenting];
}

- (NSTimeInterval)transitionDuration:(id)transitionContext {
    if (self.isPresenting) {
        return 0.45;
    }
    return 0.25;
}

- (void)animateTransition:(id)transitionContext {
    if (_isPresenting) {
        [self presentAnimateTransition:transitionContext];
    } else {
        [self dismissAnimateTransition:transitionContext];
    }
}

- (void)presentAnimateTransition:(id)transitionContext {
    MZBasePresentFadeAnimationVC *alertController = (MZBasePresentFadeAnimationVC *)[transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];

    alertController.backgroundView.alpha = 0.0;
    UIView *containerView = [transitionContext containerView];
    [containerView addSubview:alertController.view];

    [UIView animateWithDuration:0.25 animations:^{
        alertController.backgroundView.alpha = 1.0;
    } completion:^(BOOL finished) {
        [transitionContext completeTransition:YES];
    }];
}

- (void)dismissAnimateTransition:(id)transitionContext {
    MZBasePresentFadeAnimationVC *alertController = (MZBasePresentFadeAnimationVC *)[transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];

    [UIView animateWithDuration:0.25 animations:^{
        alertController.backgroundView.alpha = 0.0;
    } completion:^(BOOL finished) {
        [transitionContext completeTransition:YES];
    }];
}

@end

---

使用

只需要将需要模态出来的VC继承与MZBasePresentFadeAnimationVC即可。

- (IBAction)show:(id)sender {
    DetailViewController *vc = [[DetailViewController alloc] init];
    [self presentViewController:vc animated:YES completion:nil];
}