判断iOS的推送是否打开

[[UIApplication sharedApplication] enabledRemoteNotificationTypes]

该方法返回类型为：

UIUserNotificationType

该类型是个枚举，可以判断各个推送是否打开：

typedef enum {    UIRemoteNotificationTypeNone    = 0,    UIRemoteNotificationTypeBadge   = 1 << 0,    UIRemoteNotificationTypeSound   = 1 << 1,    UIRemoteNotificationTypeAlert   = 1 << 2,    UIRemoteNotificationTypeNewsstandContentAvailability = 1 << 3,} UIRemoteNotificationType;

注：ios8改变了获取方法

UIUserNotificationType types = [[UIApplication sharedApplication] currentUserNotificationSettings].types;