Basic Xamarin.iOS Screen Manipulation

Question

I am new to Xamarin.iOS programming, so forgive me if this is obvious.

I have a Timer that runs in the Main Application. Among other things, I need it to update fields in the Main.storyboard

In Main.cs:

public static void StartTimer()
{
    DateTime startTime;
    startTime = DateTime.UtcNow;
    var dispatcherTimer = new System.Threading.Timer(DispatcherTimer_Tick, startTime, 0, 100);
}

public static void DispatcherTimer_Tick(object state)
{
    GetTime();
    ViewController.SetFieldsTick(Vars.dcounter));
}

In the ViewController, I have a routine that updates the screen:

public static  void SetFieldsTick(int tick)
{
    switch (tick)
    {
        case 0:     // Display the Time data
        {
            UTC_Data.Text = Vars.DateStrZ;
       }
    }
}

If I declare SetFieldsTick as static, then I get the message

An object reference is required for the non-static field …

for each of the labels that I am trying to update.

If I don't declare it static, then it can refer to the labels, but I get the same error message when calling it in the Main.cs file.

Any suggestions on how to resolve this problem?

Thanks, Dan

Answer 1

I guess ViewController isn't static that's why you can't call a function from it like that, anyway your code is a bit difficult to understand, if you want to build an application with a clock or just displaying time take a look at this Xamarin.Forms example:

https://docs.microsoft.com/en-us/xamarin/xamarin-forms/xaml/xaml-basics/data-bindings-to-mvvm

Thanks to DataBinding you don't need to set the UI manually, you should try.