我在我的应用程序中使用推送通知服务。当应用程序在后台时,我能够在通知屏幕上看到通知(当我们从iOS设备顶部向下滑动时显示的屏幕)。但如果应用程序是在前台的委托方法
- (void)application:(UIApplication*)application didReceiveRemoteNotification:(NSDictionary*)userInfo
正在被调用,但通知屏幕上没有显示通知。
我想在通知屏幕上显示通知,不管应用程序是在后台还是前台。我厌倦了寻找解决办法。任何帮助都非常感激。
iOS 14 +
下面这个答案有一个不同之处,.alert已弃用,使用.banner:
class AppDelegate: NSObject, UIApplicationDelegate, UNUserNotificationCenterDelegate {
func application(
_ application: UIApplication,
didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey : Any]? = nil
) -> Bool {
UNUserNotificationCenter.current().delegate = self
return true
}
func userNotificationCenter(
_ center: UNUserNotificationCenter,
willPresent notification: UNNotification,
withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void
) {
completionHandler([.banner, .badge, .sound])
}
}
也适用于iOS 14+,不需要手动处理任何警报或视图,只需让iOS做它的事情
在里面,我们重新收到通知替换如下代码
func userNotificationCenter(
_ center: UNUserNotificationCenter,
willPresent notification: UNNotification,
withCompletionHandler completionHandler:
@escaping (UNNotificationPresentationOptions) -> Void
) {
if (UIApplication.shared.applicationState == .inactive || UIApplication.shared.applicationState == .background) {
if #available(iOS 14.0, *) {
completionHandler([[.banner, .sound]])
} else {
completionHandler([.alert, .sound])
}
} else {
if #available(iOS 14.0, *) {
completionHandler([[.banner]])
} else {
completionHandler([.alert])
}
}
}
要注意的主要事情是不要使用声音,而在前景,它不会显示横幅
当应用程序在前台显示横幅消息时,使用以下方法。
iOS 10, Swift 3/4:
// This method will be called when app received push notifications in foreground
func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void)
{
completionHandler([.alert, .badge, .sound])
}
iOS 10, Swift 2.3:
@available(iOS 10.0, *)
func userNotificationCenter(center: UNUserNotificationCenter, willPresentNotification notification: UNNotification, withCompletionHandler completionHandler: (UNNotificationPresentationOptions) -> Void)
{
//Handle the notification
completionHandler(
[UNNotificationPresentationOptions.Alert,
UNNotificationPresentationOptions.Sound,
UNNotificationPresentationOptions.Badge])
}
你还必须将你的应用委托注册为通知中心的委托:
import UserNotifications
// snip!
class AppDelegate : UIResponder, UIApplicationDelegate, UNUserNotificationCenterDelegate
// snip!
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
// set the delegate in didFinishLaunchingWithOptions
UNUserNotificationCenter.current().delegate = self
...
}
Swift 5
1)使用UNUserNotificationCenterDelegate确认委托到AppDelegate
2)在didFinishLaunch中UNUserNotificationCenter.current().delegate = self
3)在AppDelegate中实现如下方法。
func userNotificationCenter(_ center: UNUserNotificationCenter,
willPresent notification: UNNotification,
withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) {
print("Push notification received in foreground.")
completionHandler([.alert, .sound, .badge])
}
就是这样!
添加completionHandler行委托方法为我解决了同样的问题:
//Called when a notification is delivered to a foreground app.
@available(iOS 10.0, *)
func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) {
completionHandler([.alert, .badge, .sound])
}