一些常用合集

** 好记性不如烂笔头 记录一些自己在开发中经常用到的一些琐碎代码片段 会经常更新 .. **

1、目前iOS项目中要求导航栏的返回按钮只保留那个箭头，去掉后边的文字，在网上查了一些资料，最简单且没有副作用的方法就是

[UIBarButtonItem appearance]setBackButtonTitlePositionAdjustment:UIOffsetMake(0,-60)] for BarMetrics:UIBarMetricsDefault];

2、简单实现一个导航栏的下的提示视图 效果如下

- (void)showNewStatusesCount:(NSInteger)nums{

    UILabel *label = [[UILabel alloc] init];
    label.font = [UIFont systemFontOfSize:12];
    
    if (nums) {
        label.text = [NSString stringWithFormat:@"新%ld条数据", count];
    } else {
        label.text = @"暂无新数据";
    }
    
    label.backgroundColor = [UIColor colorWithRed:0/255.0  green:174/255.0 blue:22/255.0 alpha:1.0];
    label.textAlignment = NSTextAlignmentCenter;
    label.textColor = [UIColor whiteColor];
    
    label.width = self.view.frame.size.width;
    label.height = 35;
    label.x = 0;
    label.y = CGRectGetMaxY([self.navigationController navigationBar].frame) - label.frame.size.height;
    
    [self.navigationController.view insertSubview:label belowSubview:self.navigationController.navigationBar];

    [UIView animateWithDuration:.8f; animations:^{

        label.transform = CGAffineTransformMakeTranslation(0, label.frame.size.height);

    } completion:^(BOOL finished) { /
       
        [UIView animateWithDuration:duration delay:.8f options:UIViewAnimationOptionCurveEaseInOut animations:^{
            
            label.transform = CGAffineTransformIdentity;
            
        } completion:^(BOOL finished) {
           
            [label removeFromSuperview];
        }];
    }];
}

3、平时有用到更改label的行间距 使其排版看起来更美观