轉(zhuǎn)：http://www.cnblogs.com/YouXianMing/p/4187996.html
這個鏈接中的代碼也實現(xiàn)了這種效果
https://github.com/cbpowell/MarqueeLabel
最終效果如下:
原理如下:
1. 獲取文本
2. 計算文本寬度
3. 將這個Label放入ScrollView中
4. 將ScrollView的contentSize的寬度設置與文本寬度一致
5. 做動畫
*6. 邊緣的漸隱效果請使用帶透明像素的PNG圖片
//
//RootViewController.m
//
//Copyright (c) 2014年 Y.X. All rights reserved.
//
#import"RootViewController.h"
#import"YXKit.h"
#import"FontPool.h"
@interfaceRootViewController ()
@end
@implementationRootViewController
- (void)viewDidLoad
{
[super viewDidLoad];
self.view.backgroundColor=[UIColor blackColor];//注冊字體
REGISTER_FONT(bundleFont(@"新蒂小丸子體.ttf"),@"新蒂小丸子體");//獲取文本
NSString *string=@"喜歡這首情思幽幽的曲子，仿佛多么遙遠，在感嘆著前世的情緣，又是那么柔軟，在祈愿著來世的纏綿?！渡彽男氖隆罚闼屏鹆б粯拥木К?，柔柔地撥動我多情的心弦。我，蓮的心事，有誰知？我，蓮的矜持，又有誰懂？";
//初始化label
UILabel *label? ? ? = [UILabelnew];
label.text=string;
label.numberOfLines=0;
label.textColor=[UIColor cyanColor];
label.font= [UIFont fontWithName:CUSTOM_FONT(@"新蒂小丸子體",0)
size:20.f];
//計算尺寸
CGSize size? ? ? ? = [label boundingRectWithSize:CGSizeMake(0,0)];
label.frame=(CGRect){CGPointZero, size};
//初始化
ScrollViewUIScrollView *showView =\
[[UIScrollView alloc] initWithFrame:CGRectMake(0,90,320, size.height)];
showView.contentSize=size;
showView.showsHorizontalScrollIndicator=NO;
[showView addSubview:label];
[self.view addSubview:showView];
//形成邊緣的遮罩
UIImageView *imageView =\
[[UIImageView alloc] initWithFrame:CGRectMake(0,90,320, size.height)];
imageView.image= [UIImage imageNamed:@"bg"];
[self.view addSubview:imageView];
//動畫
[UIView animateKeyframesWithDuration:10delay:7options:UIViewKeyframeAnimationOptionAllowUserInteraction
animations:^{
//計算移動的距離
CGPoint point =showView.contentOffset;
point.x= size.width -320.f;
showView.contentOffset=point;
}
completion:^(BOOL finished) {
}];
}@end
