关于window
- UIWindow在显示的时候会根据UIWindowLevel进行排序的，即Level高的将排在所有Level比他低的层级的前面
- 当Level层级相同的时候，只有第一个设置为KeyWindow的显示出来，后面同级的再设置KeyWindow也不会显示
//获取到当前显示界面的controller
- (UIViewController *)getCurrentVC{
UIWindow * window = [[UIApplication sharedApplication] keyWindow];
if (window.windowLevel != UIWindowLevelNormal){
NSArray *windows = [[UIApplication sharedApplication] windows];
for(UIWindow * tmpWin in windows){
if (tmpWin.windowLevel == UIWindowLevelNormal){
window = tmpWin;
break;
}
}
}
UIViewController *result = window.rootViewController;
while (result.presentedViewController) {
result = result.presentedViewController;
}
if ([result isKindOfClass:[BasicTabBarC class]]) {
result = [(BasicTabBarC *)result selectedViewController];
}
if ([result isKindOfClass:[UINavigationController class]]) {
result = [(UINavigationController *)result topViewController];
}
return result;
}
