//
//  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labelUILabel *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