修改ios7状态栏字体颜色

 [[UIApplication sharedApplication]setStatusBarStyle:UIStatusBarStyleLightContent];

View controller-based status bar appearance   配置info.plist中

-(void)viewWillAppear:(BOOL)animated{
    [super
viewWillAppear:animated];
//    [UIApplication sharedApplication].statusBarStyle = UIStatusBarStyleLightContent;
}

-(void)viewWillDisappear:(BOOL)animated{
    [super
viewWillDisappear:animated];
//    [UIApplication sharedApplication].statusBarStyle = UIStatusBarStyleDefault;
}