iOS设计中在视图中显示滚动汉字

 

代码实现如下：

 

 

ViewController.m

#import "ViewController.h"
//导入类方法头文件
#import “BBFlashCtntLabel.h”   
@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    //初始化类对象
    BBFlashCtntLabel *label=[[BBFlashCtntLabel alloc]init];
    //背景色
    label.backgroundColor=[UIColor greenColor];
    //位置
    label.frame=CGRectMake(50, 100, 300, 50);
    label.speed=BBFlashCtntSpeedMild;
    NSString *str=@"贵州人民欢迎您来到贵州旅游O(∩_∩)O哈哈~";
    NSMutableAttributedString *att=[[NSMutableAttributedString alloc]initWithString:str];
    [att addAttribute:NSFontAttributeName value:[UIFont systemFontOfSize:30] range:NSMakeRange(0, 22)];//字体大小(长度)
    [att addAttribute:NSBackgroundColorAttributeName value:[UIColor whiteColor] range:NSMakeRange(0, 22)];//字体背景颜色
    [att addAttribute:NSForegroundColorAttributeName value:[UIColor purpleColor] range:NSMakeRange(0, 22)];//字体颜色
    label .attributedText=att;
    [self.view addSubview:label];
 
   
}

 

 

 

 

 

第三方类文件：

代码如下：（以下为带三方内库代码，可以到网络上下载）

 BBFlashCtntLabel.h
//  DebugTest
//
//  Created by iXcoder on 15/3/2.
//  Copyright (c) 2015年 iXcoder. All rights reserved.
//

#import <UIKit/UIKit.h>

typedef NS_ENUM(NSInteger, BBFlashCtntSpeed) {
    BBFlashCtntSpeedSlow = -1,
    BBFlashCtntSpeedMild,
    BBFlashCtntSpeedFast
};

@interface BBFlashCtntLabel : UIView

@property (nonatomic, strong) NSString *text;
@property (nonatomic, strong) UIFont *font;         // 默认:system(15)
@property (nonatomic, strong) UIColor *textColor;

@property (nonatomic, strong) NSAttributedString *attributedText;

@property (nonatomic, assign) BBFlashCtntSpeed speed;

// 循环滚动次数(为0时无限滚动)
@property (nonatomic, assign) NSUInteger repeatCount;

@property (nonatomic, assign) CGFloat leastInnerGap;

- (void)reloadView;

@end

BBFlashCtntLabel.m
//  DebugTest
//
//  Created by iXcoder on 15/3/2.
//  Copyright (c) 2015年 iXcoder. All rights reserved.
//

#import "BBFlashCtntLabel.h"

@interface BBFlashCtntLabel()
{
    BOOL seted;
    
    BOOL moveNeed;
    
    CGFloat rate;
}

@property (nonatomic, strong) UIView *innerContainer;

@end

@implementation BBFlashCtntLabel

- (void)awakeFromNib
{
    [super awakeFromNib];
    self.font = [UIFont systemFontOfSize:15];
    self.textColor = [UIColor blackColor];
    self.speed = BBFlashCtntSpeedMild;
    self.repeatCount = 0;
    self.leastInnerGap = 10.f;
    self.clipsToBounds = YES;
    rate = 80.f;
    [self setup];
}

- (instancetype)initWithFrame:(CGRect)frame
{
    if (self = [super initWithFrame:frame]) {
        self.font = [UIFont systemFontOfSize:15];
        self.textColor = [UIColor blackColor];
        self.speed = BBFlashCtntSpeedMild;
        self.repeatCount = 0;
        self.leastInnerGap = 10.f;
        self.clipsToBounds = YES;
        [self setup];
    }
    return self;
}

- (void)setSpeed:(BBFlashCtntSpeed)speed
{
    _speed = speed;
    switch (_speed) {
        case BBFlashCtntSpeedFast:
            rate = 90.;
            break;
        case BBFlashCtntSpeedMild:
            rate = 75;
            break;
        case BBFlashCtntSpeedSlow:
            rate = 40.;
            break;
        default:
            break;
    }
    [self reloadView];
}

- (void)setLeastInnerGap:(CGFloat)leastInnerGap
{
    _leastInnerGap = leastInnerGap;
    [self reloadView];
}

- (void)setText:(NSString *)text
{
    _text = text;
    _attributedText = nil;
    [self reloadView];
}

- (void)setAttributedText:(NSAttributedString *)attributedText
{
    _attributedText = [self setAttributedTextDefaultFont:attributedText];
    _text = nil;
    [self reloadView];
}

- (NSAttributedString *)setAttributedTextDefaultFont:(NSAttributedString *)attrText
{
    NSMutableAttributedString *rtn = [[NSMutableAttributedString alloc] initWithAttributedString:attrText];
    void (^enumerateBlock)(id, NSRange, BOOL *) = ^(id value, NSRange range, BOOL *stop) {
        if (!value || [value isKindOfClass:[NSNull class]]) {
           
            [rtn addAttribute:NSFontAttributeName
                        value:self.font
                        range:range];
        }
    };
    [rtn enumerateAttribute:NSFontAttributeName
                    inRange:NSMakeRange(0, rtn.string.length)
                    options:0
                 usingBlock:enumerateBlock];
    return rtn;
}

- (void)setFont:(UIFont *)font
{
    _font = font;
    [self reloadView];
}

- (void)setTextColor:(UIColor *)textColor
{
    _textColor = textColor;
    [self reloadView];
}

- (void)setup
{
    if (seted) {
        return ;
    }
    self.innerContainer = [[UIView alloc] initWithFrame:self.bounds];
    self.innerContainer.backgroundColor = [UIColor clearColor];
    self.innerContainer.autoresizingMask = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth;
    
    [self addSubview:self.innerContainer];
    
    seted = YES;
}

- (void)reloadView
{
    [self.innerContainer.layer removeAnimationForKey:@"move"];
    for (UIView *sub in self.innerContainer.subviews) {
        if ([sub isKindOfClass:[UILabel class]]) {
            [sub removeFromSuperview];
        }
    }
    CGFloat width = [self evaluateContentWidth];
    moveNeed = width > self.bounds.size.width;
    CGRect f = CGRectMake(0, 0, width, self.bounds.size.height);
    UILabel *label = [[UILabel alloc] initWithFrame:f];
    label.backgroundColor = [UIColor clearColor];
    if (self.text) {
        label.text = self.text;
        label.textColor = self.textColor;
        label.font = self.font;
    } else {
        label.attributedText = self.attributedText;
    }
    
    [self.innerContainer addSubview:label];
    if (moveNeed) {
        CGRect f1 = CGRectMake(width + self.leastInnerGap, 0, width, f.size.height);
        UILabel *next = [[UILabel alloc] initWithFrame:f1];
        next.backgroundColor = [UIColor clearColor];
        if (self.text) {
            next.text = self.text;
            next.textColor = self.textColor;
            next.font = self.font;
        } else {
            next.attributedText = self.attributedText;
        }
        
        [self.innerContainer addSubview:next];
        
        CAKeyframeAnimation *moveAnimation = [CAKeyframeAnimation animationWithKeyPath:@"transform.translation.x"];
        moveAnimation.keyTimes = @[@0., @0.191, @0.868, @1.0];
        moveAnimation.duration = width / rate;
        moveAnimation.values = @[@0, @0., @(- width - self.leastInnerGap)];
        moveAnimation.repeatCount = self.repeatCount == 0 ? INT16_MAX : self.repeatCount;
        moveAnimation.timingFunction = [CAMediaTimingFunction functionWithName:@"linear"];
        [self.innerContainer.layer addAnimation:moveAnimation forKey:@"move"];
    }
}

- (CGFloat)evaluateContentWidth
{
    CGFloat width = 0.f;
    NSStringDrawingOptions options = NSStringDrawingTruncatesLastVisibleLine |
    NSStringDrawingUsesLineFragmentOrigin |
    NSStringDrawingUsesFontLeading;
    if (_text.length > 0) {
        NSDictionary *attr = @{NSFontAttributeName : self.font};
        CGSize size = [_text boundingRectWithSize:CGSizeMake(CGFLOAT_MAX, self.bounds.size.height) options:options attributes:attr context:nil].size;
        width = size.width;
        
    } else if (_attributedText.length > 0) {
        CGSize size = [_attributedText boundingRectWithSize:CGSizeMake(CGFLOAT_MAX, self.bounds.size.height) options:options context:nil].size;
        width = size.width;
    }
    
    return width;
}

@end