喷枪打字

实现原理比较简单,这里不做过多介绍.

[objc] view
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#import "ViewController.h"

@interface ViewController ()

@property (weak, nonatomic) IBOutlet UILabel *titleLabel;

@property (copy , nonatomic)NSString *contentStr;

@end

[objc] view
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- (void)viewDidLoad

{

[super viewDidLoad];

NSThread *thread = [[NSThread alloc]initWithTarget:self selector:@selector(animationLabel) object:nil];

[thread start];

self.contentStr = @"人生最宝贵的是生命，生命属于人只有一次。一个人的生命应当这样度过：当他回忆往事的时候，他不致因虚度年华而悔恨，也不致因碌碌无为而羞愧；在临死的时候，他能够说：“我的整个生命和全部精力，都已献给世界上最壮丽的事业——为人类的解放而斗争。”";

}

[objc] view
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- (void)animationLabel

{

for (NSInteger i = 0; i < self.contentStr.length; i++)

{

[self performSelectorOnMainThread:@selector(refreshUIWithContentStr:) withObject:[self.contentStr substringWithRange:NSMakeRange(0, i+1)] waitUntilDone:YES];

[NSThread sleepForTimeInterval:0.3];

}

}

[objc] view
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- (void)refreshUIWithContentStr:(NSString *)contentStr

{

self.titleLabel.text = contentStr;

}

最终效果: