Ios NSMutableAttributedString通过动画完成 -（无效）设置行程标签：（BOOL）行程标签 { _strokeLabel=strokeLabel； if（_strokeLabel）{ _计时器=[NSTimer scheduledTimerWithTimeInterval:0.4目标：自选择器：@selector（setStroketThrough）userInfo:nil repeats:NO]； }否则{ [自动取消行程]； } } -（空）定位行程 { NSMutableAttributedString*attributedString=[[NSMutableAttributedString alloc]initWithAttributedString:self.attributedText]； 对于（i=1；i

，这里有两个函数可以完成此任务。

- (void)setStrokeLabel:(BOOL)strokeLabel
{
    _strokeLabel = strokeLabel;

    if (_strokeLabel) {
        _timer = [NSTimer scheduledTimerWithTimeInterval:0.4 target:self selector:@selector(setStrokeThrough) userInfo:nil repeats:NO];
    } else {
        [self cancelStrokeThrough];
    }
}

- (void)setStrokeThrough
{
    NSMutableAttributedString *attributedString = [[NSMutableAttributedString alloc] initWithAttributedString:self.attributedText];

    for (NSUInteger i = 1; i <= [attributedString length]; i++) {
        [attributedString addAttribute:NSStrikethroughStyleAttributeName
                                 value:[NSNumber numberWithInt:1]
                                 range:NSMakeRange(0, i)];
        self.attributedText = attributedString;
    }
}

- (void)cancelStrokeThrough
{
    NSMutableAttributedString *attributedString = [[NSMutableAttributedString alloc] initWithAttributedString:self.attributedText];
    [attributedString removeAttribute:NSStrikethroughStyleAttributeName
                                range:NSMakeRange(0, [attributedString length])];
    self.attributedText = attributedString;

}

注释

为了限制动画时间，我用字符块而不是字符块来制作动画。字符串越长，字符块就越长

__块uu弱业务解释见

self-performBlock是NSObject的扩展，由和实现 也

代码假定您已定义self.label成员

---

这不是一个可设置动画的属性。你最好自己设置一个计时器，然后一个字母一个字母地写。谢谢@Borrden，尽管我为它设置了一个NSTimer，但结果并不明显。我不知道你所说的“结果不明显”是什么意思，我希望它一个字母一个字母地慢慢敲打，\u timer=[NSTimer scheduledTimerWithTimeInterval:0.5目标：自选择器：@selector（SetStroketThrough）userInfo:nil repeats:NO]；出现错误？该计时器不会重复，但您应该使用所有相关代码更新您的问题。

    BOOL setStrokethrough(UILabel *label, NSRange range)
    {
        if (range.location >= [label.attributedText length])
            return FALSE;

        if (range.location + range.length > [label.attributedText length])
            range.length = [label.attributedText length] - range.location;

        NSMutableAttributedString *attributedString = [[NSMutableAttributedString alloc] initWithAttributedString:label.attributedText];

        [attributedString addAttribute:NSStrikethroughStyleAttributeName
                                 value:@(NSUnderlineStyleSingle)
                                 range:range];

        label.attributedText = attributedString;
        return TRUE;
    }

    -(void)animateSetStrokethroughDuration:(float)duration
    {
        __block float const stepDuration = 0.1;
        float steps = duration / stepDuration;
        __block NSRange range = NSMakeRange(0, ceil((float)[self.label.attributedText length] / steps));

        void (^__block fn)();
        void (^__block __weak weakfn)();

        weakfn = fn = ^(){
            if (!setStrokethrough(self.label, range))
                return;
            range = NSMakeRange(range.location + range.length, range.length);
            [self performBlock:weakfn afterDelay:stepDuration];
        };
        fn();
    }