辉光UIView的category

//
//  UIView+GlowView.h
//  YouXianClock
//
//  Created by YouXianMing on 14-12-21.
//  Copyright (c) 2014年 YouXianMing. All rights reserved.
//

#import <UIKit/UIKit.h>

@interface UIView (GlowView)

@property (nonatomic, strong) NSNumber *GCDTimerInterval; // 定时器的时间间隔，给float值
@property (nonatomic, strong) NSNumber *glowDuration;     // layer动画的时间长度，给float值
@property (nonatomic, strong) NSNumber *glowLayerOpacity; // 设置glowLayer的动画透明度的程度，给float值，范围在[0,1]

- (void)createGlowLayerWithColor:(UIColor *)color glowRadius:(CGFloat)radius;
- (void)startGlow;
- (void)glowToGlowLayerOnce;
- (void)glowToNormalLayerOnce;

@end

//
//  UIView+GlowView.m
//  YouXianClock
//
//  Created by YouXianMing on 14-12-21.
//  Copyright (c) 2014年 YouXianMing. All rights reserved.
//

#import "UIView+GlowView.h"
#import <objc/runtime.h>

#define GLOWVIEW_LAYER_FLAG     @"UIView+GlowView"

@interface UIView ()

@property (strong, nonatomic) dispatch_source_t  dispatchSource;
@property (strong, nonatomic) NSNumber          *glowViewShowFlag;

@end

@implementation UIView (GlowView)

#pragma mark - 动态添加了属性
static char dispatchSourceTimerFlag;
- (void)setDispatchSource:(dispatch_source_t)dispatchSource {
    objc_setAssociatedObject(self, &dispatchSourceTimerFlag, dispatchSource, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}
- (dispatch_source_t)dispatchSource {
    return objc_getAssociatedObject(self, &dispatchSourceTimerFlag);
}

static char charGlowViewShowFlag;
- (void)setGlowViewShowFlag:(NSNumber *)glowViewShowFlag {
    objc_setAssociatedObject(self, &charGlowViewShowFlag, glowViewShowFlag, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}
- (NSNumber *)glowViewShowFlag {
    return objc_getAssociatedObject(self, &charGlowViewShowFlag);
}

static char GCDTimerIntervalFlag;
- (void)setGCDTimerInterval:(NSNumber *)GCDTimerInterval {
    objc_setAssociatedObject(self, &GCDTimerIntervalFlag, GCDTimerInterval, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}
- (NSNumber *)GCDTimerInterval {
    return objc_getAssociatedObject(self, &GCDTimerIntervalFlag);
}

static char glowLayerOpacityFlag;
- (void)setGlowLayerOpacity:(NSNumber *)glowLayerOpacity {
    objc_setAssociatedObject(self, &glowLayerOpacityFlag, glowLayerOpacity, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}
- (NSNumber *)glowLayerOpacity {
    return objc_getAssociatedObject(self, &glowLayerOpacityFlag);
}

static char glowDurationFlag;
- (void)setGlowDuration:(NSNumber *)glowDuration {
    objc_setAssociatedObject(self, &glowDurationFlag, glowDuration, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}
- (NSNumber *)glowDuration {
    return objc_getAssociatedObject(self, &glowDurationFlag);
}



#pragma mark - 方法
- (void)createGlowLayerWithColor:(UIColor *)color glowRadius:(CGFloat)radius {
    UIGraphicsBeginImageContextWithOptions(self.bounds.size, NO, [UIScreen mainScreen].scale);
    [self.layer renderInContext:UIGraphicsGetCurrentContext()];
    UIBezierPath* path =     [UIBezierPath bezierPathWithRect:(CGRect){CGPointZero, CGSizeMake(self.bounds.size.width, self.bounds.size.height)}];
    [color setFill];
    [path fillWithBlendMode:kCGBlendModeSourceAtop alpha:1.0];
    
    CALayer *glowLayer      = [CALayer layer];
    glowLayer.name          = GLOWVIEW_LAYER_FLAG;
    glowLayer.frame         = self.bounds;
    glowLayer.contents      = (__bridge id)UIGraphicsGetImageFromCurrentImageContext().CGImage;
    glowLayer.shadowOpacity = 1.0f;
    glowLayer.shadowOffset  = CGSizeMake(0, 0);
    glowLayer.shadowColor   = (color == nil ? [UIColor redColor].CGColor : color.CGColor);
    glowLayer.shadowRadius  = (radius > 0 ? radius : 2.f);
    glowLayer.opacity       = 0.f; // 开始时候的透明度为0
    [self.layer addSublayer:glowLayer];

    UIGraphicsEndImageContext();
}

- (void)startGlow {
    [self.layer.sublayers enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
        CALayer *layer = obj;
        
        // 找到了layer才进行下面的操作
        if ([layer.name isEqualToString:GLOWVIEW_LAYER_FLAG]) {
            
            if (self.glowViewShowFlag == nil) {
                self.glowViewShowFlag = [NSNumber numberWithBool:NO];
            }
            
            if (self.dispatchSource == nil) {
                self.dispatchSource =                 dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER, 0, 0, dispatch_get_main_queue());
                dispatch_source_set_timer(self.dispatchSource, dispatch_time(DISPATCH_TIME_NOW, 0),
                                          NSEC_PER_SEC * (self.GCDTimerInterval == nil ? 1 : self.GCDTimerInterval.floatValue), 0);
                dispatch_source_set_event_handler(self.dispatchSource, ^{
                    if (self.glowViewShowFlag.boolValue == NO) {
                        self.glowViewShowFlag = @(YES);
                        
                        // 做动画，从透明到显示出来
                        CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:@"opacity"];
                        
                        if (self.glowLayerOpacity != nil) {
                            animation.fromValue = @(0.f);
                            animation.toValue   = [NSNumber numberWithFloat:self.glowLayerOpacity.floatValue];
                            layer.opacity       = self.glowLayerOpacity.floatValue;
                        } else {
                            animation.fromValue = @(0.f);
                            animation.toValue   = @(0.8f);
                            layer.opacity       = 0.8;
                        }
                        
                        if (self.glowDuration != nil) {
                            animation.duration = self.glowDuration.floatValue;
                        } else {
                            animation.duration = 0.8;
                        }
                        
                        [layer addAnimation:animation forKey:nil];
                    } else {
                        self.glowViewShowFlag = @(NO);
                        
                        // 做动画
                        CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:@"opacity"];
                        animation.fromValue         = [NSNumber numberWithFloat:layer.opacity];
                        animation.toValue           = @(0.f);
                        
                        if (self.glowDuration != nil) {
                            animation.duration = self.glowDuration.floatValue;
                            layer.opacity      = 0.f;
                        } else {
                            animation.duration = 0.8;
                            layer.opacity      = 0.f;
                        }
                        
                        [layer addAnimation:animation forKey:nil];
                    }
                });
                
                dispatch_resume(self.dispatchSource);
            }
        }
    }];
}

- (void)glowToGlowLayerOnce {
    [self.layer.sublayers enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
        CALayer *layer = obj;
        
        // 找到了layer才进行下面的操作
        if ([layer.name isEqualToString:GLOWVIEW_LAYER_FLAG]) {
                // 做动画，从透明到显示出来
                CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:@"opacity"];
                if (self.glowLayerOpacity != nil) {
                    animation.fromValue = @(0.f);
                    animation.toValue   = [NSNumber numberWithFloat:self.glowLayerOpacity.floatValue];
                    layer.opacity       = self.glowLayerOpacity.floatValue;
                } else {
                    animation.fromValue = @(0.f);
                    animation.toValue   = @(0.8f);
                    layer.opacity       = 0.8;
                }
                
                if (self.glowDuration != nil) {
                    animation.duration = self.glowDuration.floatValue;
                } else {
                    animation.duration = 0.8;
                }
                [layer addAnimation:animation forKey:nil];
        }
    }];
}

- (void)glowToNormalLayerOnce {
    [self.layer.sublayers enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
        CALayer *layer = obj;
        
        // 做动画
        CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:@"opacity"];
        animation.fromValue         = [NSNumber numberWithFloat:layer.opacity];
        animation.toValue           = @(0.f);
        
        if (self.glowDuration != nil) {
            animation.duration = self.glowDuration.floatValue;
            layer.opacity      = 0.f;
        } else {
            animation.duration = 0.8;
            layer.opacity      = 0.f;
        }
        
        [layer addAnimation:animation forKey:nil];
    }];
}

@end

//
//  ViewController.m
//  Glow
//
//  Created by YouXianMing on 14/12/21.
//  Copyright (c) 2014年 YouXianMing. All rights reserved.
//

#import "ViewController.h"
#import "UIView+GlowView.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
 
    self.view.backgroundColor = [UIColor blackColor];
    
    // 普通label
    UILabel *label      = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, 320, 100)];
    label.center        = self.view.center;
    label.font          = [UIFont fontWithName:@"HelveticaNeue-UltraLight" size:50.f];
    label.textAlignment = NSTextAlignmentCenter;
    label.text          = @"YouXianMing";
    label.textColor     = [UIColor redColor];
    
    
    label.GCDTimerInterval = @(2.f);
    label.glowDuration     = @(1.f);
    label.glowLayerOpacity = @(0.8f);

    [label createGlowLayerWithColor:[UIColor yellowColor] glowRadius:4.f];
    [label startGlow];
    
    [self.view addSubview:label];
    
}

@end