ios小技巧

  1. 获取app版本号
    [[[NSBundle mainBundle] infoDictionary] objectForKey:@"CFBundleShortVersionString"]; //app版本号
    [[[NSBundle mainBundle] infoDictionary] objectForKey:@"CFBundleVersion"]; //build
    
  2. 获取系统版本号
    [UIDevice currentDevice].systemVersion;
    
  3. 判断字符串是否为空
    我习惯把它定义成宏,数组字典类似。
    if (str == nil || (NSNull *)str == [NSNull null] || str.length == 0)
    {}
    
  4. 打印沙盒路径
    NSLog(@"app = %@",NSHomeDirectory());
    
  5. 不想让tableView显示无用的cell分割线
    self.tableView.tableFooterView = [[UIView alloc] init];
    
  6. NSLog输出NSRangeCGRect等结构体
    NSString中的方法:
    NSStringFromCGPoint(CGPoint point);
    NSStringFromCGVector(CGVector vector);
    NSStringFromCGSize(CGSize size);
    NSStringFromCGRect(CGRect rect);
    NSStringFromCGAffineTransform(CGAffineTransform transform);
    NSStringFromUIEdgeInsets(UIEdgeInsets insets);
    NSStringFromUIOffset(UIOffset offset);
    NSLog(@"%@",NSStringFromCGPoint(CGPointZero));
    
  7. 隐藏navigationBar
    有时候我们使用navigationController,需要首页隐藏导航栏其他页面显示导航栏。
    - (void)viewWillAppear:(BOOL)animated
    {
        [super viewWillAppear:animated];
        [self.navigationController setNavigationBarHidden:YES animated:YES];
    }
    - (void)viewWillDisappear:(BOOL)animated
    {
        [super viewWillDisappear:animated];
        [self.navigationController setNavigationBarHidden:NO animated:YES];
    }