我在使用 Xamarin 的 Android 上進行本地通知時遇到問題。每次應用程式在前臺或打開時都會顯示本地通知。如果我重新啟動，通知不會顯示。有一個RECEIVE_BOOT_COMPLETED BroadcastReceiver，但我不知道它是否在重新啟動時觸發。
我無法弄清楚出了什么問題。我把所有東西都檢查了三倍，感覺好像少了一些小東西。
編輯：我想我已經解決了應用程式關閉的通知，這要歸功于這個執行緒：應用程式關閉時廣播接收器不作業。本質上，如果除錯，應用程式需要在關閉后重新打開，以便呼叫接收器。
我使用此檔案設定本地通知：https ://docs.microsoft.com/en-us/xamarin/xamarin-forms/app-fundamentals/local-notifications
AndroidManifest.cs
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android" android:versionCode="5" android:versionName="1.0.2.1" package="com.business.myapp" android:installLocation="preferExternal">
<uses-sdk android:minSdkVersion="21" android:targetSdkVersion="31" />
<application android:label="MyApp" android:theme="@style/MainTheme" android:supportsRtl="true" android:icon="@mipmap/icon"></application>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
<uses-permission android:name="com.android.alarm.permission.SET_ALARM" />
</manifest>
報警處理器.cs
using Android.Content;
using MyApp.Business.Services;
using MyApp.Global;
using MyApp.Utils;
using Serilog;
using System;
namespace MyApp.Droid
{
/// <summary>
/// Handle notification receiving.
///
/// https://github.com/xamarin/xamarin-forms-samples/blob/main/LocalNotifications/LocalNotifications/LocalNotifications.Android/AlarmHandler.cs
/// </summary>
[BroadcastReceiver(
Enabled = true,
Exported = true,
Label = "Local Notifications Broadcast Receiver")]
public class AlarmHandler : BroadcastReceiver
{
/// <summary>
/// Called when a notification is shown.
/// </summary>
/// <param name="context"></param>
/// <param name="intent"></param>
public override void OnReceive(Context context, Intent intent)
{
// if (intent?.Extras != null)
// {
if (!Settings.DailyNotificationEnabled) return;
// do not show notification if it is not time based on the settings time value.
// this handles cases where the user changes the notification time multiple times.
/* Disabled on 3/6/2022 to see if this helps notifications.
var timeSpan = DateTime.Now - NotificationDateTime.GetDailyNotificationDateTime();
var absTotalSeconds = Math.Abs(timeSpan.TotalSeconds);
if (absTotalSeconds > 59 && absTotalSeconds < 86399) return;
*/
string title = intent.GetStringExtra(AndroidNotificationManager.TitleKey);
string message = intent.GetStringExtra(AndroidNotificationManager.MessageKey);
title = Constants.NotificationOffllineTitle;
message = Constants.NotificationOffllineMessage;
try
{
var votdHttpRequest = new VotdHttpRequest();
var votdApiDto = votdHttpRequest.MakeApiCall(DateTime.Now, Settings.TwoLetterISOLanguageName);
title = $"{DateTime.Now.ToShortDateString()} {votdApiDto.@ref} ({votdApiDto.ver.ToUpper()})";
var scripture = Settings.DisplayKjvVersion ? votdApiDto.en_scrip_kjv : votdApiDto.en_scrip;
message = Remove.RecursiveHtmlDecode(scripture);
}
catch (Exception ex)
{
Log.Error(ex, "Failed recieving notification.");
}
AndroidNotificationManager manager = AndroidNotificationManager.Instance ?? new AndroidNotificationManager();
manager.Show(title, message);
// }
}
}
}
AndroidNotificationManager.cs
using System;
using Android.App;
using Android.Content;
using Android.Graphics;
using Android.OS;
using AndroidX.Core.App;
using MyApp.Notifications;
using Xamarin.Forms;
using AndroidApp = Android.App.Application;
[assembly: Dependency(typeof(MyApp.Droid.AndroidNotificationManager))]
namespace MyApp.Droid
{
/// <summary>
/// Daily notification manager.
/// </summary>
public class AndroidNotificationManager : INotificationManager
{
#region Private Fields
const string channelId = "default";
const string channelName = "Default";
const string channelDescription = "The default channel for notifications.";
bool channelInitialized = false;
int messageId = 0;
int pendingIntentId = 0;
NotificationManager manager;
#endregion
#region Public Properties
public const string TitleKey = "title";
public const string MessageKey = "message";
public event EventHandler NotificationReceived;
public static AndroidNotificationManager Instance { get; private set; }
public AndroidNotificationManager() => Initialize();
#endregion
#region Constructor
#endregion
#region Private Methods
/// <summary>
/// Create the notification channel.
/// </summary>
void CreateNotificationChannel()
{
manager = (NotificationManager)AndroidApp.Context.GetSystemService(AndroidApp.NotificationService);
if (Build.VERSION.SdkInt >= BuildVersionCodes.O)
{
var channelNameJava = new Java.Lang.String(channelName);
var channel = new NotificationChannel(channelId, channelNameJava, NotificationImportance.Default)
{
Description = channelDescription
};
manager.CreateNotificationChannel(channel);
}
channelInitialized = true;
}
/// <summary>
/// Get the time of notification in UTC ticks.
/// </summary>
/// <param name="notifyTime"></param>
/// <returns></returns>
long GetNotifyTime(DateTime notifyTime)
{
DateTime utcTime = TimeZoneInfo.ConvertTimeToUtc(notifyTime);
double epochDiff = (new DateTime(1970, 1, 1) - DateTime.MinValue).TotalSeconds;
long utcAlarmTime = utcTime.AddSeconds(-epochDiff).Ticks / 10000;
return utcAlarmTime; // milliseconds
}
#endregion
#region Public Methods
/// <summary>
/// Initialize the notification channel
/// </summary>
public void Initialize()
{
if (Instance == null)
{
CreateNotificationChannel();
Instance = this;
}
}
/// <summary>
/// Schedule a notification.
/// </summary>
/// <param name="title"></param>
/// <param name="message"></param>
/// <param name="notifyTime">Time of notification.</param>
public void SendNotification(string title, string message, int id, DateTime? notifyTime = null)
{
if (!channelInitialized)
{
CreateNotificationChannel();
}
if (notifyTime != null)
{
var intent = CreateIntent(id);
intent.PutExtra(TitleKey, title);
intent.PutExtra(MessageKey, message);
intent.SetIdentifier(id.ToString());
PendingIntent pendingIntent = PendingIntent.GetBroadcast(
AndroidApp.Context,
pendingIntentId ,
intent,
PendingIntentFlags.Immutable);
long triggerTime = GetNotifyTime(notifyTime.Value);
long millisecondsRepeating = AlarmManager.IntervalDay;
AlarmManager alarmManager = AndroidApp.Context.GetSystemService(Context.AlarmService) as AlarmManager;
alarmManager.SetRepeating(AlarmType.RtcWakeup, triggerTime, millisecondsRepeating, pendingIntent);
}
else
{
Show(title, message);
}
}
/// <summary>
/// Called when a notifiation is received.
/// </summary>
/// <param name="title"></param>
/// <param name="message"></param>
public void ReceiveNotification(string title, string message)
{
var args = new NotificationEventArgs()
{
Title = title,
Message = message,
};
NotificationReceived?.Invoke(null, args);
}
/// <summary>
/// Display the notification in the notification area.
/// </summary>
/// <param name="title"></param>
/// <param name="message"></param>
public void Show(string title, string message)
{
Intent intent = new Intent(AndroidApp.Context, typeof(MainActivity));
intent.PutExtra(TitleKey, title);
intent.PutExtra(MessageKey, message);
PendingIntent pendingIntent = PendingIntent.GetActivity(
AndroidApp.Context,
pendingIntentId ,
intent,
PendingIntentFlags.UpdateCurrent | PendingIntentFlags.Immutable);
var textStyle = new NotificationCompat.BigTextStyle();
textStyle.BigText(message);
textStyle.SetSummaryText(title);
NotificationCompat.Builder builder = new NotificationCompat.Builder(AndroidApp.Context, channelId)
.SetContentIntent(pendingIntent)
// .SetContentTitle(title) // not required with big text style
// .SetContentText(message) // not required with big text style
.SetLargeIcon(BitmapFactory.DecodeResource(AndroidApp.Context.Resources, Resource.Drawable.icon_votd))
.SetSmallIcon(Resource.Drawable.icon_votd)
.SetDefaults((int)NotificationDefaults.Sound | (int)NotificationDefaults.Vibrate)
.SetStyle(textStyle);
if (Build.VERSION.SdkInt >= BuildVersionCodes.Lollipop)
builder.SetVisibility((int)NotificationVisibility.Public);
Notification notification = builder.Build();
notification.Flags = NotificationFlags.AutoCancel;
manager.Notify(messageId , notification);
}
/// <summary>
/// Delete a notification.
/// </summary>
/// <param name="id"></param>
public void DeleteNotification(int id)
{
Intent intent = new Intent(AndroidApp.Context, typeof(AlarmHandler));
PendingIntent pendingIntent = PendingIntent.GetBroadcast(
AndroidApp.Context,
id, intent,
PendingIntentFlags.CancelCurrent | PendingIntentFlags.Immutable);
AlarmManager alarmManager = AndroidApp.Context.GetSystemService(Context.AlarmService) as AlarmManager;
alarmManager.Cancel(pendingIntent);
}
private Intent CreateIntent(int id)
{
return new Intent(Android.App.Application.Context, typeof(AlarmHandler)).SetAction("LocalNotifierIntent" id);
}
public void CancelAlarm(int id)
{
var intent = CreateIntent(id);
var pendingIntent = PendingIntent.GetBroadcast(
Android.App.Application.Context,
0,
intent,
PendingIntentFlags.UpdateCurrent | PendingIntentFlags.Immutable);
var alarmManager = GetAlarmManager();
alarmManager.Cancel(pendingIntent);
var notificationManager = NotificationManagerCompat.From(Android.App.Application.Context);
notificationManager.CancelAll();
notificationManager.Cancel(id);
}
private AlarmManager GetAlarmManager()
{
var alarmManager = Android.App.Application.Context.GetSystemService(Context.AlarmService) as AlarmManager;
return alarmManager;
}
#endregion
}
}
引導接收器.cs
using Android.App;
using Android.Content;
using MyApp.Notifications;
using MyApp.Utils;
using System;
using Xamarin.Forms;
namespace MyApp.Droid.Notifications
{
/// <summary>
/// Used to reschedule notifications on boot. Android notifications are deleted when the OS is rebooted.
/// </summary>
[BroadcastReceiver(
Enabled = true,
Label = "Reboot complete receiver",
Exported = true)]
[IntentFilter(new[] { Android.Content.Intent.ActionBootCompleted })]
public class BootReceiver : BroadcastReceiver
{
/// <summary>
/// Called on boot.
/// </summary>
/// <param name="context"></param>
/// <param name="intent"></param>
public override void OnReceive(Context context, Intent intent)
{
//if (intent.Action == "android.intent.action.BOOT_COMPLETED")
//{
// ScheduleDailyNotification();
//}
ScheduleDailyNotification();
}
/// <summary>
/// Schedule the daily notification.
/// </summary>
private void ScheduleDailyNotification()
{
if (Settings.DailyNotificationEnabled)
{
var notificationManager = DependencyService.Get<INotificationManager>();
var notificationDateTime = NotificationDateTime.GetDailyNotificationDateTime();
notificationManager.SendNotification(
Global.Constants.NotificationOffllineTitle,
Global.Constants.NotificationOffllineMessage,
Global.Constants.DailyNotificationId,
//DateTime.Now.AddSeconds(60));
notificationDateTime);
}
}
}
}
uj5u.com熱心網友回復：
我討厭從互聯網上洗掉一個問題。
收到的啟動問題是在啟動接收器中使用依賴注入。例外：You must call Xamarin.Forms.Forms.Init(); prior to using this property.我只是實體化了該類，而不是為此實體使用 DI。
在關閉應用程式時未顯示通知的問題上，這對我有用：https ://stackoverflow.com/a/60197247/814891
在清單中靜態注冊我的 BroadcastReceiver (BR)，應用適當的意圖過濾器，使用 JobIntentService（并在清單中注冊）處理從我的 BR 呼叫的作業后，我仍然得到不一致的結果。
完成我上面列出的所有操作后，即使應用程式已關閉，您也應該能夠發送 ADB 命令來激活您的廣播并處理您的服務中的作業。這在某些時候對我有用，但不是所有時候。
本文介紹了對 BR 的限制。“從 Android 3.1 開始，如果用戶從未啟動過相應的應用程式或用戶通過 Android 選單明確停止了應用程式，Android 系統默認將所有接收者排除在接收意圖之外”（AKA 用戶執行強制停止）
當我通過除錯啟動應用程式，然后在我的設備上將其關閉時，我的 ADB 命令永遠不會激活我的 BR。但是，在我的除錯會話結束后，當我在我的設備上打開應用程式并將其關閉時，我可以通過 ADB 命令激活我的 BR。
發生這種情況是因為當您除錯應用程式，然后在設備上手動將其關閉時，Android 認為這是強制停止，因此為什么我的 BR 無法激活，直到我重新打開設備上的應用程式而不進行除錯。
在互聯網上搜索了幾個小時，但找不到我的解決方案，所以我想我會把它貼在這里，以防萬一一些可憐的不幸的靈魂遇到了我曾經遇到的同樣奇怪的功能。
快樂編碼:)
轉載請註明出處，本文鏈接：https://www.uj5u.com/caozuo/449252.html
標籤：xamarin xamarin.forms xamarin.android 通知 安卓通知