iOS小知识点

• UIButton中文字位置

// 设置contentHorizontalAlignment 
button.contentHorizontalAlignment = UIControlContentHorizontalAlignmentLeft;

• stringByAppendingPathComponent和stringByAppendingString的区别

stringByAppendingPathComponent和stringByAppendingString的区别- 前者相当于自己拼接“/”+string

• 导航栏显示和隐藏

 - (void)viewWillAppear:(BOOL)animated{
 [super viewWillAppear:animated];
 // 进入这个控制器时隐藏导航栏 
[self.navigationController setNavigationBarHidden:YES animated:animated];
}

 - (void)viewWillDisappear:(BOOL)animated{ 
// 显示导航栏 
 [self.navigationController setNavigationBarHidden:NO animated:animated];}

• app内字体总体变大

 新app在iPhone6上字体明显大了好多， 后来排查原来启动图片设计标注的750的图片给成了1024的