默认状态下
状态栏的内容为黑色，背景色为白色
想要改变状态栏的字体，电源，运营商等内容的颜色需要
下面代码是将状态栏内容改为白色
在info.plist 文件中更改添加 View controller-based status bar appearance == NO
然后添加代码，将[UIApplication sharedApplication].statusBarStyle = UIStatusBarStyleLightContent;
想要改变状态栏背景颜色：
下面代码是将背景色改为黑色
CGFloatstatwidth = [[UIApplicationsharedApplication]statusBarFrame].size.width;
CGFloatstatheight = [[UIApplicationsharedApplication]statusBarFrame].size.height;
UIView*statusBarView=[[UIViewalloc]initWithFrame:CGRectMake(0,0, statwidth, statheight)];
statusBarView.backgroundColor=[UIColorblackColor];
