设置电池状态栏为白色

1、首先需要再info.plist中添加一项View controller-based status bar appearance为no

2、在需要的地方添加代码

• (void)viewWillAppear:(BOOL)animated
  {
  [super viewWillAppear:animated];
  [[UIApplication sharedApplication] setStatusBarStyle:UIStatusBarStyleLightContent animated:NO];
  }
• (void)viewWillDisappear:(BOOL)animated
  {
  [super viewWillDisappear:animated];
  [[UIApplication sharedApplication] setStatusBarStyle:UIStatusBarStyleDefault animated:NO];
  }