UICollisionBehavior с iOS9, кажется, останавливается на 1,5 пункта от границы: моя ошибка или Apple?

Question

В моем приложении я использую UIKit Dynamics, включая UICollisionBehavior, чтобы отсканировать меню при его открытии и при закрытии. Код, который я использую для этого, приведен ниже. Это отлично работает для iOS8. Однако с iOS9 (включая только что выпущенную бета-версию iOS9.1) я обнаружил странную проблему. На первый взгляд меню, которое я подпрыгиваю от этой анимации, не было закрыто после открытия, а затем закрыло его. Более внимательно, я нахожу, что границы для UICollisionBehavior вычисляются с одинаковыми значениями в iOS8 и iOS9.

Открытие границы открытия окна: (798,330) to (1024,330) Что представляет собой линию на экране, где нижняя часть меню должна окончательно отдохнуть после открытия и подпрыгивания.

Граница закрытия меню: (798,-280) to (1024,-280) Что представляет собой линию, за пределами экрана, где верхняя часть меню должна окончательно отдыхать после закрытия и подпрыгивания.

Проблема возникает в iOS9, где меню UIView на самом деле не заканчивается окончательно на этих границах. После открытия, рама меню выглядит следующим образом с iOS9:

(798, -1.5; 226, 330) [Это: (х, у, ш, ч)]

и после закрытия, рамка меню выглядит следующим образом:

(798, -278.5; 226, 330)

НО, это должно быть на самом деле:

(798, 0; 226, 330) (после открытия)

(798, -280; 226, 330) (после закрытия)

Кто-нибудь еще видел эти вопросы с iOS9 и столкновения поведения?

Я собираюсь положить хак в свой код (ищите «HACK» ниже), который я сделаю выборочным для iOS9, но мне действительно не нравятся эти хаки!

BounceAnimation.h

// 
// BounceAnimation.h 
// Petunia 
// 
// Created by Christopher Prince on 12/18/14. 
// Copyright (c) 2014 Spastic Muffin, LLC. All rights reserved. 
// 

// Animates an object through a straight line path, up, down, left or right until it lands, after which it bounces. This requires iOS8 or later. 

#import <Foundation/Foundation.h> 

@interface BounceAnimation : NSObject 

// distnace is for the viewToAnimate to travel until it lands and bounces, in points. You must set this before calling run. 
- (instancetype) initWithReferenceView: (UIView *) referenceView viewToAnimate: (UIView *) viewToAnimate andDistance: (CGFloat) distance; 

// Direction and distance will be obtained from animateToPoint, and should be consistent with the constraints for the direction property below. I.e., the animateToPoint should be down, left, right, or up from the origin of the viewToAnimate. 
- (instancetype) initWithReferenceView: (UIView *) referenceView viewToAnimate: (UIView *) viewToAnimate andFinalPoint: (CGPoint) animateToPoint; 

// One shot animation. You can only call run once. 
- (void) run; 

// Called when animation completes, if given. Called when all the bouncing is done. 
@property (nonatomic, strong) void (^completion)(void); 

// Called when first contact is made with the boundary, just as the first bounce is about to begin. 
@property (nonatomic, strong) void (^firstImpactCallback)(void); 

// Only keeps weak references to the views passed in the init method. 
@property (nonatomic, weak, readonly) UIView *referenceView; 
@property (nonatomic, weak, readonly) UIView *viewToAnimate; 

// Rate at which the object accelerates towards the boundary. Same units as magnitude for UIGravityBehavior. Defaults to 1.0. 
@property (nonatomic) CGFloat accelerationRate; 

// Defaults to 0. Units are points per second. 
@property (nonatomic) CGFloat initialVelocity; 

// This is a unit vector. 
// dx (first component) is rightwards; e.g., dx=0, no right/left; dx=-1, is left one unit 
// dy (second component) is downwards; e.g., dy=1, down one unit. 
// Defaults to (0, 1), downwards. 
// Right now, dx and dy can be 0, 1, or -1. One of dx and dy must be 0. 
@property (nonatomic, readonly) CGVector direction; 

@end 

BounceAnimation.m

// 
// BounceAnimation.m 
// Petunia 
// 
// Created by Christopher Prince on 12/18/14. 
// Copyright (c) 2014 Spastic Muffin, LLC. All rights reserved. 
// 

#import "BounceAnimation.h" 
#import "Vector.h" 
#import "UIDevice+Extras.h" 

@interface BounceAnimation()<UIDynamicAnimatorDelegate, UICollisionBehaviorDelegate> 
{ 
    UIDynamicAnimator *_animator; 
    UIGravityBehavior *_gravityBehavior; 
    UICollisionBehavior *_collision; 
    UIDynamicItemBehavior *_velocity; 
    CGPoint _linearVelocity; 
    CGFloat _distanceInPoints; 
    BOOL _calledFirstImpactCallback; 
} 

@property (nonatomic, weak) UIView *referenceView; 
@property (nonatomic, weak) UIView *viewToAnimate; 
@property (nonatomic) CGVector direction; 

@end 

#define INITIAL_GRAVITY_MAGNITUDE 1.0 

@implementation BounceAnimation 

- (void) setupWithReferenceView: (UIView *) referenceView andViewToAnimate: (UIView *) viewToAnimate; 
{ 
    AssertIf([UIDevice ios7OrEarlier], @"Don't have at least iOS8!"); 

    self.referenceView = referenceView; 
    self.viewToAnimate = viewToAnimate; 

    _animator = [[UIDynamicAnimator alloc] initWithReferenceView:referenceView]; 
    _animator.delegate = self; 

    _gravityBehavior = [[UIGravityBehavior alloc] initWithItems:@[viewToAnimate]]; 
    _gravityBehavior.magnitude = INITIAL_GRAVITY_MAGNITUDE; 

    _velocity = [[UIDynamicItemBehavior alloc] initWithItems:@[viewToAnimate]]; 
} 

// referenceView is just the view on top of which we're doing our animation. E.g., it could be self.view of a view controller. viewToAnimate must be a subview of the reference view. 
- (instancetype) initWithReferenceView: (UIView *) referenceView viewToAnimate: (UIView *) viewToAnimate andDistance: (CGFloat) distanceInPoints; 
{ 
    self = [super init]; 
    if (self) { 
     AssertIf(distanceInPoints <= 0.0, @"Invalid distance: %f", _distanceInPoints); 
     _distanceInPoints = distanceInPoints; 
     [self setupWithReferenceView:referenceView andViewToAnimate:viewToAnimate]; 
     [self setDirection:CGVectorMake(0.0, 1.0)]; 
    } 

    return self; 
} 

- (instancetype) initWithReferenceView: (UIView *) referenceView viewToAnimate: (UIView *) viewToAnimate andFinalPoint: (CGPoint) animateToPoint; 
{ 
    self = [super init]; 
    if (self) { 
     // Need to compute distance and direction. 
     CGVector direction = [Vector subFirst:[Vector fromPoint:animateToPoint] from:[Vector fromPoint:viewToAnimate.frameOrigin]]; 
     SPASLogDetail(@"direction after subtraction: %@", NSStringFromCGVector(direction)); 

     // Special case: No direction because same start and finish. 
     if (direction.dy + direction.dx == 0.0) { 
      _distanceInPoints = 0.0; 
     } 
     else { 
      direction = [Vector normalize:direction]; // vectorNormalize(direction); 
      _distanceInPoints = [Vector distanceFromPoint:viewToAnimate.frameOrigin toPoint:animateToPoint]; 
     } 

     SPASLogDetail(@"finalPoint: %@, direction: %@, distance: %f", NSStringFromCGPoint(animateToPoint), NSStringFromCGVector(direction), _distanceInPoints); 

     [self setupWithReferenceView:referenceView andViewToAnimate:viewToAnimate]; 
     [self setDirection:direction]; 
    } 

    return self; 
} 

- (void) setInitialVelocity:(CGFloat)initialVelocity; 
{ 
    _initialVelocity = initialVelocity; 
    // Only positive speeds in the velocity are relevant. Negative speeds reduce the velocity, they don't go the other direction. 
    _linearVelocity = 
     CGPointMake(initialVelocity * fabs(_direction.dx), 
        initialVelocity * fabs(_direction.dy)); 
} 

- (void) setAccelerationRate:(CGFloat)accelerationRate; 
{ 
    _accelerationRate = accelerationRate; 
    _gravityBehavior.magnitude = accelerationRate; 

} 

// I'm only doing left, right, up, down animations because of the problem of rotating the viewToAnimate. I'm not sure I'll ever have a case where I want a rotated animated view. (Hmmm. If I want to do some kind of continuous animation, arbitrary direction with non-rotated objects could be cool!) 
- (void) setDirection:(CGVector)direction; 
{ 
    if (_collision) { 
     [_animator removeBehavior:_collision]; 
     _collision = nil; 
    } 

    if (_distanceInPoints == 0.0) { 
     // Why bother? 
     SPASLogDetail(@"Zero distance"); 
     return; 
    } 

    // 9/24/15; HACK 
    //_distanceInPoints += 1.5; 

    // Since we're doing vector operations with one of the init methods above, the following seems risky! 
    //AssertIf(direction.dy != 0.0 && direction.dy != -1.0 && direction.dy != 1.0, @"Invalid dy: %f", direction.dy); 
    //AssertIf(direction.dx != 0.0 && direction.dx != -1.0 && direction.dx != 1.0, @"Invalid dx: %f", direction.dx); 

    _direction = direction; 
    _gravityBehavior.gravityDirection = direction; 

    _collision = [[UICollisionBehavior alloc] initWithItems:@[self.viewToAnimate]]; 
    _collision.collisionDelegate = self; 

    CGPoint startBoundary; 
    CGPoint endBoundary; 

#define SMALL_VALUE 0.05 
    BOOL (^closeToZero)(CGFloat) = ^(CGFloat value) { 
     if (value > -SMALL_VALUE && value < SMALL_VALUE) { 
      return YES; 
     } 
     else { 
      return NO; 
     } 
    }; 

    if (closeToZero(direction.dx)) { 
     // Vertical motion. 
     CGFloat yBoundary = direction.dy * _distanceInPoints + self.viewToAnimate.frameY; 
     if (direction.dy > 0.0) { 
      // If we're going down, then we need to add the height of the self.viewToAnimate to our boundary. This is because the origin coords are in the *upper*, left of the viewToAnimate. 
      yBoundary += self.viewToAnimate.frameHeight; 
     } 

     startBoundary = CGPointMake(self.viewToAnimate.frameX, yBoundary); 
     endBoundary = CGPointMake(self.viewToAnimate.frameX + self.viewToAnimate.frameWidth, yBoundary); 
    } 
    else { 
     // Horizontal motion. 
     CGFloat xBoundary = direction.dx * _distanceInPoints + self.viewToAnimate.frameX; 
     if (direction.dx > 0.0) { 
      // If we're going to the right, then we need to add the width of the self.viewToAnimate to our boundary. This is because the origin coords are in the upper, *left* of the viewToAnimate. 
      xBoundary += self.viewToAnimate.frameWidth; 
     } 

     startBoundary = CGPointMake(xBoundary, self.viewToAnimate.frameY); 
     endBoundary = CGPointMake(xBoundary, self.viewToAnimate.frameY + self.viewToAnimate.frameHeight); 
    } 

    SPASLog(@"startBoundary: %@, endBoundary: %@", NSStringFromCGPoint(startBoundary), NSStringFromCGPoint(endBoundary)); 

    [_collision addBoundaryWithIdentifier:@"barrier" 
           fromPoint:startBoundary 
            toPoint:endBoundary]; 

    [_animator addBehavior:_collision]; 
} 

- (void) run; 
{ 
    if (_collision) { 
     [_animator addBehavior:_gravityBehavior]; 
     [_velocity addLinearVelocity:_linearVelocity forItem:self.viewToAnimate]; 
     [_animator addBehavior:_velocity]; 
    } 
    else { 
     if (self.completion) { 
      self.completion(); 
     } 
    } 
} 

#pragma mark - UIDynamicAnimatorDelegate methods 

- (void)dynamicAnimatorDidPause:(UIDynamicAnimator*)animator; 
{ 
    if (self.completion) { 
     self.completion(); 
    } 
} 

#pragma mark - 

#pragma mark - UICollisionBehaviorDelegate methods 

// This isn't the method that gets called in our case. 
//- (void)collisionBehavior:(UICollisionBehavior*)behavior beganContactForItem:(id <UIDynamicItem>)item1 withItem:(id <UIDynamicItem>)item2 atPoint:(CGPoint)p; 

- (void)collisionBehavior:(UICollisionBehavior*)behavior beganContactForItem:(id <UIDynamicItem>)item withBoundaryIdentifier:(id <NSCopying>)identifier atPoint:(CGPoint)p; 
{ 
    if (!_calledFirstImpactCallback) { 
     _calledFirstImpactCallback = YES; 
     if (self.firstImpactCallback) { 
      self.firstImpactCallback(); 
     } 
    } 
} 

#pragma mark - 


@end 

Answer 1

Я работаю в Swift, и я вижу такое же поведение, как и вы с 1,5 очками офсетных. Кажется, что он не связан с разрешением устройства (1x, 2x или 3x), все имеют сдвиг в 1,5 точки.

Однако, используя в пути на основе API, проблема, кажется, не быть там больше:

let collisionBehavior: UICollisionBehavior = ... 
let topLeft: CGPoint = ... 
let bottomLeft: CGPoint = ... 

let path = CGPathCreateMutable() 
CGPathMoveToPoint(path, nil, topLeft.x, topLeft.y) 
CGPathAddLineToPoint(path, nil, bottomLeft.x, bottomLeft.y) 
let bezierPath = UIBezierPath(CGPath: path) 
collisionBehavior.addBoundaryWithIdentifier("myID", forPath: bezierPath) 

Преобразование это Objective-C достаточно легко:

UICollisionBehavior *collisionBehavior = ... 
CGPoint topLeft = ... 
CGPoint bottomLeft = ... 

CGMutablePathRef path = CGPathCreateMutable(); 
CGPathMoveToPoint(path, nil, topLeft.x, topLeft.y); 
CGPathAddLineToPoint(path, nil, bottomLeft.x, bottomLeft.y); 
UIBezierPath *bezierPath = [UIBezierPath bezierPathWithCGPath: path]; 
[collisionBehavior addBoundaryWithIdentifier: @"myID" forPath: path];