//

//  UIView+MotionEffect.h

//

//  Copyright (c) 2014年 Nick Jensen. All rights reserved.

//

#import <UIKit/UIKit.h>

@interface UIView (MotionEffect)

@property (nonatomic, strong) UIMotionEffectGroup  *effectGroup;

- (void)addXAxisWithValue:(CGFloat)xValue YAxisWithValue:(CGFloat)yValue;

- (void)removeSelfMotionEffect;

@end

//

//  UIView+MotionEffect.m

//

//  Copyright (c) 2014年 Nick Jensen. All rights reserved.

//

#import "UIView+MotionEffect.h"

#import <objc/runtime.h>

static char motionEffectFlag;

@implementation UIView (MotionEffect)

-(void)setEffectGroup:(UIMotionEffectGroup *)effectGroup

{

    // 清除掉关联

    objc_setAssociatedObject(self, &motionEffectFlag,

                             nil, OBJC_ASSOCIATION_RETAIN_NONATOMIC);

    // 建立关联

    objc_setAssociatedObject(self, &motionEffectFlag,

                             effectGroup, OBJC_ASSOCIATION_RETAIN_NONATOMIC);

}

-(UIMotionEffectGroup *)effectGroup

{

    // 返回关联

    return objc_getAssociatedObject(self, &motionEffectFlag);

}

- (void)addXAxisWithValue:(CGFloat)xValue YAxisWithValue:(CGFloat)yValue

{

    NSLog(@"%p", &motionEffectFlag);

    if ((xValue >= ) && (yValue >= ))

    {

        UIInterpolatingMotionEffect *xAxis = [[UIInterpolatingMotionEffect alloc] initWithKeyPath:@"center.x" type:UIInterpolatingMotionEffectTypeTiltAlongHorizontalAxis];

        xAxis.minimumRelativeValue = @(-xValue);

        xAxis.maximumRelativeValue = @(xValue);

        UIInterpolatingMotionEffect *yAxis = [[UIInterpolatingMotionEffect alloc] initWithKeyPath:@"center.y" type:UIInterpolatingMotionEffectTypeTiltAlongVerticalAxis];

        yAxis.minimumRelativeValue = @(-yValue);

        yAxis.maximumRelativeValue = @(yValue);

        // 先移除效果再添加效果

        self.effectGroup.motionEffects = nil;

        [self removeMotionEffect:self.effectGroup];

        self.effectGroup.motionEffects = @[xAxis, yAxis];

        // 给view添加效果

        [self addMotionEffect:self.effectGroup];

    }

}

- (void)removeSelfMotionEffect

{

    [self removeMotionEffect:self.effectGroup];

}

@end

- (void)viewDidLoad {

    [super viewDidLoad];

    UIImageView *imageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"show"]];

    [self.view addSubview:imageView];

    imageView.center = self.view.center;

    imageView.effectGroup = [UIMotionEffectGroup new];

    [imageView addXAxisWithValue:.f YAxisWithValue:.f];

}