它是活的吗？ Xamarin、C# 上的服务器连接

Question

I wold like to do a is it alive? for check for my server connection on Xamarin.Forms. If the connection breaks, it will show an alert message. When the connection is restore the alert message will desapier.

I have a http get request who checks the connection but I don't know how code the rest of the code. I need a fuction who will running on the backgound checking the connection on all the pages of my app.

This is my request:

    public async void Alive() {
        try {
            Uri uri = new Uri(Settings.basePath + "/alive");
            return await client.GetAsync(uri);
        } catch {
            return null;
        }
    }

How could I do this?

Answer 1

I wold like to do a is it alive? for check for my server connection on Xamarin.Forms. If the connection breaks, it will show an alert message. When the connection is restore the alert message will desapier.

You can create method in App.cs. every 5 second to check server connection.

IDynamicAlert alert = DependencyService.Get<IDynamicAlert>();
    public App()
    {
        InitializeComponent();

        var seconds = TimeSpan.FromSeconds(5);
        Xamarin.Forms.Device.StartTimer(seconds, () =>
            {

               
                if (CheckConnection())
                {
                    if (alert != null)
                    {
                        alert.Dismiss();
                    }

                    return true;
                }
                else
                {
                    alert.Show("alert message", "connection is break!");
                    return true;

                }
            });

        MainPage =new NavigationPage( new simplecontrol.Page26());
       
    }
   
    private bool  CheckConnection()
    {
        //check your server connection
       if ()
        {
            //connection is alive.

        }
        else
        {
            //connection is break. 
        }
    }

I create custom ALertDialog, please following code;

create interface in project share code.

 public interface IDynamicAlert
{
    void Show(string title, string message);
  
    void Dismiss();
}

Then implementing this interface in Android platform.

[assembly: Dependency(typeof(DynamicAlert))]
 namespace FormsSample.Droid
{
public  class DynamicAlert : IDynamicAlert
{
    Android.App.AlertDialog.Builder builder;
    AlertDialog alert;
    public void Dismiss()
    {
        alert.Hide();
    }

    public void Show(string title, string message)
    {
        alert.SetTitle(title);
        alert.SetMessage(message);
        alert.SetButton("OK", (sender, args) => { });
        alert.SetCancelable(false);
        alert.Show();                  
    }
  
    public DynamicAlert()
    {
        builder = new AlertDialog.Builder(MainActivity.mac);
         alert = builder.Create();
    }           
}
 }

Create static MainActivity mac im MianActivity.cs.

 public static MainActivity mac;
    protected override void OnCreate(Bundle savedInstanceState)
    {
       
        TabLayoutResource = Resource.Layout.Tabbar;
        ToolbarResource = Resource.Layout.Toolbar;
        
        base.OnCreate(savedInstanceState);
        mac = this;               
        global::Xamarin.Forms.Forms.Init(this, savedInstanceState); 
        LoadApplication(new App());
    }