[Xamarin] 用Service 來製作一個Notification的時鐘 (转帖)

這篇利用來製作一個會出現在Notification的時鐘,來敘述一下 Service,在你製作的App被關閉時,可以透過Service繼續運行你想處理的部分,當然Service 也有其生命周期

01_-_StartedServiceLifecycle
接下來我們來介紹一下今天的案例:
shot_000013

當按下開始報時服務按鈕時,就會啟動Service,並且更新Notification 如下:
shot_000016

之後就算離開APP他的秒數也是會繼續跑的跟現在時間同步,之後按下停止報時服務才會將其終結..
1.首先我們得在專案裡面建立一個 RemindService.cs 當然這是自己命名的 ,他必須繼承Service

namespace XamarinServiceTest
{
    //此 attribute 一定要加
    [Service]
    public class RemindService : Service
    {
    ...

之後因為方便我對Notification 更新資料,我在這 ReminService 寫一個專門更新 Notification的method :

/// <summary>
/// 簡單包裝Notification 
/// 詳情可以參考 
/// http://no2don.blogspot.com/2013/07/xamarin-notification.html
/// </summary>
/// <param name="id">Notify id</param>
/// <param name="content">Notify content</param>
private void NotiSomething(int id, string content)
{
    NotificationCompat.Builder builder = new NotificationCompat.Builder(this)
       .SetContentTitle(content)
       .SetSmallIcon(Resource.Drawable.Icon2);
 
 
    var notificationManager = (NotificationManager)GetSystemService(Context.NotificationService);
    //都用同一組id
    notificationManager.Notify(id, builder.Build());
}

因為每秒更新,所以我必須 宣告一隻 Timer

private System.Timers.Timer TimerMainTask { get; set; }

在Service 開始時,只要複寫 OnStartCommand 即可,在內容我就寫啟動 TimerMainTask讓TimerMainTask每一秒鐘都去更新Notification資訊

 
/// <summary>
/// 開始Service 開始時呼叫
/// </summary>
/// <param name="intent"></param>
/// <param name="flags"></param>
/// <param name="startId"></param>
/// <returns></returns>
public override StartCommandResult OnStartCommand(Android.Content.Intent intent, StartCommandFlags flags, int startId)
{
    TimerMainTask = new System.Timers.Timer(1000);
    TimerMainTask.Elapsed += TimerMainTask_Elapsed;
    TimerMainTask.Start();
    NotiSomething(4, "開始進入" + System.DateTime.Now.ToString("hh:mm:ss"));
 
    return StartCommandResult.Sticky;
}
 
/// <summary>
/// 每次timer 做的事情
/// 設計為一秒跑一次 
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
void TimerMainTask_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
{
    NotiSomething(1, "當麻報時-" + System.DateTime.Now.ToString("hh:mm:ss"));
}

再來就是當Service 停止時,必須要將TimerMainTask關掉:

/// <summary>
/// 當Service 停止時呼叫
/// </summary>
public override void OnDestroy()
{
    NotiSomething(4, "已停止" + System.DateTime.Now.ToString("hh:mm:ss"));
    TimerMainTask.Stop();
    base.OnDestroy();
}

2.第一步完成後,接下來就是在AndroidManifest.xml 加入Service服務

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.donma.xamarin.servicetest" android:installLocation="auto">
    <uses-sdk android:minSdkVersion="8" android:targetSdkVersion="8" />
    <application android:label="XamarinServiceTest"></application>
  <service android:name="XamarinServiceTest.RemindService"></service>
</manifest>

就是加入 <service android:name="XamarinServiceTest.RemindService"></service>

3. 主程式中將RemindService 呼叫起來:

var btnStart = FindViewById<Button>(Resource.Id.btnStart);
btnStart.Click += delegate
{
    StartService(new Intent(this, typeof(RemindService)));
    Toast.MakeText(this, "開始Service", ToastLength.Short).Show();
};

關閉RemindService

var btnEnd = FindViewById<Button>(Resource.Id.btnEnd);
btnEnd.Click += delegate
    {
        StopService(new Intent(this, typeof(RemindService)));
        Toast.MakeText(this, "停止Service", ToastLength.Short).Show();
    };

結果:

shot_000013
shot_000016

shot_000014
shot_000015

reference :

http://docs.xamarin.com/guides/android/application_fundamentals/services/part_1_-_started_services

https://developer.android.com/training/run-background-service/index.html

posted on 2013-11-27 01:15  王员外王爷  阅读(337)  评论(0编辑  收藏  举报

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