UILabel的混合显示动画效果

//
// MixedColorProgressViewController.m
// Animations
//
// Created by YouXianMing on 16/1/5.
// Copyright © 2016年 YouXianMing. All rights reserved.
//

#import "MixedColorProgressViewController.h"
#import "UIView&＃43;SetRect.h"
#import "GCD.h"&＃64;interface MixedColorProgressViewController ()&＃64;property (nonatomic, strong) UIView *upView;
&＃64;property (nonatomic, strong) UILabel *upLabel;
&＃64;property (nonatomic, strong) UIView *downView;
&＃64;property (nonatomic, strong) UILabel *downLabel;&＃64;property (nonatomic, strong) GCDTimer *timer;&＃64;end&＃64;implementation MixedColorProgressViewController- (void)setup {[super setup];/*给upView的frame值做动画才是label能够混色显示的核心upView(红色背景) &＃61;&＃61;&＃61;> upLabel(白色底字)| || || || |downView(白色背景) &＃61;&＃61;&＃61;> downLabel(红色底字)*/// 上面一层
{// 红色背景_upView &＃61; [[UIView alloc] initWithFrame:CGRectMake(0, 0, 220, 17)];_upView.center &＃61; self.view.center;_upView.layer.cornerRadius &＃61; 2.f;_upView.backgroundColor &＃61; [UIColor redColor];_upView.layer.masksToBounds &＃61; YES; // 核心(不让subview显示超出范围)
[self.view addSubview:_upView];// 白色底字_upLabel &＃61; [[UILabel alloc] initWithFrame:_upView.bounds];_upLabel.font &＃61; [UIFont fontWithName:&＃64;"HelveticaNeue-Thin" size:13];_upLabel.text &＃61; &＃64;"YouXianMing - iOS Programmer";_upLabel.textColor &＃61; [UIColor whiteColor];_upLabel.textAlignment &＃61; NSTextAlignmentCenter;[_upView addSubview:_upLabel];}// 下面一层
{// 白色背景_downView &＃61; [[UIView alloc] initWithFrame:CGRectMake(0, 0, 220, 17)];_downView.center &＃61; self.view.center;_downView.layer.cornerRadius &＃61; 2.f;_downView.backgroundColor &＃61; [UIColor whiteColor];[self.view addSubview:_downView];// 红色底字_downLabel &＃61; [[UILabel alloc] initWithFrame:_downView.bounds];_downLabel.textColor &＃61; [UIColor redColor];_downLabel.font &＃61; [UIFont fontWithName:&＃64;"HelveticaNeue-Thin" size:13];_downLabel.text &＃61; &＃64;"YouXianMing - iOS Programmer";_downLabel.textAlignment &＃61; NSTextAlignmentCenter;[_downView addSubview:_downLabel];}// 显示上面一层
[self.view bringSubviewToFront:_upView];// 给上面一层的frame值做动画_timer &＃61; [[GCDTimer alloc] initInQueue:[GCDQueue mainQueue]];[_timer event:^{[UIView animateWithDuration:0.5f delay:0.f usingSpringWithDamping:3.f initialSpringVelocity:0 options:0 animations:^{_upView.width &＃61; arc4random() % 220;} completion:nil];} timeInterval:NSEC_PER_SEC];[_timer start];
}&＃64;end