Triggering Activity Indicator in Xamarin Forms

Question

I have an icon on my Xamarin.Forms app, which when it is clicked, I would like to change it to an activity indicator. It looks as though I should use a Trigger, Event Trigge

Answer 1

James' answer is correct, however, I prefer to use the page's own IsBusy property, for two reasons:

1. I'm lazy and I don't want to set-up INotifyPropertyChanged implementation if I don't have to
2. XF is suppossed to use that property to display a notification by default. This doesn't appear to be working, but if it ever does, this approach will already have us covered to take advantage of it

The only difference with James' answer (besides deleting the INPC implementation) is that you need to give the page a name (x:Name="myPage") and then declare the binding using a reference to it using {Binding Source={x:Reference myPage}, Path=IsBusy} for the ActivityIndicator's IsVisible and IsRunning values.

i.e.:

MainPage.xaml:

    ...
    
    ...

MainPage.xaml.cs:

...
async void OnDoSomethingLong(...)
{
    if (!this.IsBusy)
    {
        try
        {
            this.IsBusy = true;

            //await long operation here, i.e.:
            await Task.Run(() => {/*your long code*/});
        }
        finally
        {
            this.IsBusy = false;
        }
    }
}
...