Refactoring UI

Platforms/Android/MainApplication.cs

@@ -1,5 +1,6 @@
 using Android.App;
 using Android.Runtime;
+using HeartRateMonitorAndroid.Services;
 
 namespace HeartRateMonitorAndroid;
 
@@ -12,4 +13,12 @@ public class MainApplication : MauiApplication
     }
 
     protected override MauiApp CreateMauiApp() => MauiProgram.CreateMauiApp();
+
+    public override void OnCreate()
+    {
+        base.OnCreate();
+        
+        // 设置Android平台特定的服务助手
+        ServiceHelper.Current = new Platforms.Android.AndroidServiceHelper();
+    }
 }