xamarin forms listview auto refresh - xamarin.forms

Question

I'm new to Xamarin.Forms and I'm making a Listview that needs to update every time I insert new information in the database, so far I can display the info of my list and add it via a PHP file but I can't make it refresh automatically.
namespace Proyect
{
[XamlCompilation(XamlCompilationOptions.Compile)]
public partial class Alarms : ContentPage
{
public Alarms ()
{
InitializeComponent();
AlarmsList.ItemTemplate = new DataTemplate(typeof(Cells.AlarmsCell)); //Template of the Alarms
this.LoadAlarms();
}
private async void LoadAlarms()
{
try
{
HttpClient client = new HttpClient();
client.BaseAddress = new Uri("Http://192.168.0.13");
string url = string.Format("/Proyect/alarmscode.php?");
var response = await client.GetAsync(url);
var result = response.Content.ReadAsStringAsync().Result;
var jsonalarms = JsonConvert.DeserializeObject<ObservableCollection<GetAlarms>>(result);
AlarmsList.ItemsSource = jsonalarms;
}
catch (Exception e)
{
await DisplayAlert("ERROR", e + "", "OK");
return;
}
}
}
}

Answer 1

Can you try to keep the same ObservableCollection and update its content instead of setting a new ObservableCollection every time?
namespace Proyect
{
[XamlCompilation(XamlCompilationOptions.Compile)]
public partial class Alarms : ContentPage
{
private ObservableCollection<GetAlarms> _itemsSource = null;
public Alarms()
{
InitializeComponent();
AlarmsList.ItemTemplate = new DataTemplate(typeof(Cells.AlarmsCell)); //Template of the Alarms
_itemsSource = new ObservableCollection<GetAlarms>();
AlarmsList.ItemsSource = _itemsSource;
this.LoadAlarms();
}
private async void LoadAlarms()
{
try
{
HttpClient client = new HttpClient();
client.BaseAddress = new Uri("Http://192.168.0.13");
string url = string.Format("/Proyect/alarmscode.php?");
var response = await client.GetAsync(url);
var result = response.Content.ReadAsStringAsync().Result;
var jsonalarms = JsonConvert.DeserializeObject<ObservableCollection<GetAlarms>>(result);
_itemsSource.Clear();
foreach (var alarm in jsonalarms)
{
_itemsSource.Add(alarm);
}
}
catch (Exception e)
{
await DisplayAlert("ERROR", e + "", "OK");
return;
}
}
}
}

Answer 2

Device.StartTimer (new TimeSpan (0, 0, 10), () => {
// do something every 10 seconds
return true; // runs again, or false to stop
});