iOS学习 - 23 加载本地 txt文件，NSMutableParagraphStyle 段落格式，缩放动画

Posted 2020-08-09

思路：

　　1.new 一个 Empty 后缀为 .txt 文件，内容随笔拷贝一段

　　2.用 NSString 接收本地文件，再用一个标题拼接字符串

　　3.创建一个 NSMutableParagraphStyle 实例，设置标题居中、标题距离正文间隔

　　4.创建一个 NSMutableParagraphStyle 实例，设置正文左对齐、每段开头缩进 10

　　5.创建一个基础动画的实例，用代理监听动画结束

话不多说上代码

#pragma mark -- 拼接字符
- (void)loadData:(NSString *)filename {
    
    //第一个段落
    NSMutableParagraphStyle *first = [[NSMutableParagraphStyle alloc]init];
    first.alignment = NSTextAlignmentCenter;
    first.lineSpacing = 10;
    
    //第二个段落
    NSMutableParagraphStyle *second = [[NSMutableParagraphStyle alloc]init];
    //从左开始写
    second.alignment = NSTextAlignmentLeft;
    //首行缩进
    second.firstLineHeadIndent = 10;
    //间距
    second.lineSpacing = 10;
    
    UIFont *titleFont = [UIFont systemFontOfSize:16];
    UIFont *contextFont = [UIFont systemFontOfSize:13];
    
    NSMutableAttributedString *str1 = [[NSMutableAttributedString alloc]initWithString:@"游戏许可及服务协议" attributes:@{NSParagraphStyleAttributeName:first,NSFontAttributeName:titleFont}];
    
    //标题拼接正文，正文前加换行符
    NSString *str = [NSString stringWithFormat:@"\n%@",filename];
    
    NSMutableAttributedString *str2 = [[NSMutableAttributedString alloc]initWithString:str attributes:@{NSParagraphStyleAttributeName:second,NSFontAttributeName:contextFont}];
    
    [str1 appendAttributedString:str2];
    _textView.attributedText = str1;
}

#pragma mark -- 关闭动画
- (void)closeAniamtion:(UIView *)view {
    CABasicAnimation *animation = [CABasicAnimation animation];
    animation.keyPath = @"transform.scale";
    animation.toValue = @0.9;
    animation.duration = 0.4;
    animation.delegate = self;
    animation.removedOnCompletion = NO;
    animation.fillMode = kCAFillModeForwards;
    [view.layer addAnimation:animation forKey:@"closeAnimation"];
}

#pragma mark -- 本地 txt 文件内容
- (NSString *)filename {
    //本地 txt 文件
    NSString *path = [[NSBundle mainBundle]pathForResource:@"浅遇时光，静好无恙.txt" ofType:nil];
    //取出内容
    NSString *filename = [[NSString alloc]initWithContentsOfFile:path encoding:NSUTF8StringEncoding error:nil];
    return filename;
}

#pragma mark -- 代理监听动画停止
- (void)animationDidStop:(CAAnimation *)anim finished:(BOOL)flag {

    if ([_bgView.layer animationForKey:@"closeAnimation"] == anim) {
        [_bgView removeFromSuperview];
    }
}

完整代码在 github 上，点我下载