我有一个函数scheduleFutureLocalNotifications()
在Swift代码中创建64 UILocalNotification
将在未来触发。调度导致滞后和延迟用户界面的UILocalNotification
最初的功能是在viewDidLoad()
处调用的,但是这会在启动应用程序时造成延迟。
接下来,该函数在活动应用程序期间被调用,但是这导致了不可预知的用户界面的暂停或滞后。
最后,当应用程序在收到UIApplicationDidEnterBackground
通知后转换到背景时,该功能被移动以触发,但这会导致iOS短暂滞后,因为本地通知在后台准备好。这在旧设备上显得更为明显。
问:
1 - 如何减少延迟,提高用户界面响应 创建本地通知?
2 - 可以采用哪些更好的技术来安排64 通知?
3 - 函数
scheduleFutureLocalNotifications()
可以调用哪个更好的时间?
代码:
import UIKit
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
scheduleFutureLocalNotifications()
}
func scheduleFutureLocalNotifications() {
// Remove all previous local notifications
let application = UIApplication.sharedApplication()
application.cancelAllLocalNotifications()
// Set new local notifications to fire over the coming 64 days
for nextLocalNotification in 1...64 {
// Add calendar day
let addDayComponent = NSDateComponents()
addDayComponent.day = nextLocalNotification
let calendar = NSCalendar.currentCalendar()
let nextDate = calendar.dateByAddingComponents(addDayComponent, toDate: NSDate(), options: [])
// Set day components for next fire date
let nextLocalNotificationDate = NSCalendar.currentCalendar()
let components = nextLocalNotificationDate.components([.Year, .Month, .Day], fromDate: nextDate!)
let year = components.year
let month = components.month
let day = components.day
// Set notification fire date
let componentsFireDate = NSDateComponents()
componentsFireDate.year = year
componentsFireDate.month = month
componentsFireDate.day = day
componentsFireDate.hour = 0
componentsFireDate.minute = 0
componentsFireDate.second = 5
let fireDateLocalNotification = calendar.dateFromComponents(componentsFireDate)!
// Schedule local notification
let localNotification = UILocalNotification()
localNotification.fireDate = fireDateLocalNotification
localNotification.alertBody = ""
localNotification.alertAction = ""
localNotification.timeZone = NSTimeZone.defaultTimeZone()
localNotification.repeatInterval = NSCalendarUnit(rawValue: 0)
localNotification.applicationIconBadgeNumber = nextLocalNotification
application.scheduleLocalNotification(localNotification)
}
}
}
通过在'dispatch_async' – Paulw11
包裹调用'scheduleFutureLocalNotifications'分派代码到后台线程谢谢@ Paulw11你能解释一下吗?你是否打算做以下事情? dispatch_get_global_queue(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_BACKGROUND,0),{() - > void self.scheduleFutureLocalNotifications()}) – user4806509
你能解释一下更多关于到底是什么吗? – user4806509