MaterialTextField can't set text property

🐛 Bug Report

You can’t set the text value of the MaterialTextField, it crashes the APP. This doesn’t happen in the Simulator. Bug happening in iPhone 6S 13.3.1 and with either XF.Material 1.6.0 or 1.5.8

Expected behavior

The text value of the MaterialTextField changes.

Reproduction steps

Created a new blank Xamarin Forms solution. MainPage.xaml

<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:d="http://xamarin.com/schemas/2014/forms/design"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
             xmlns:ui="clr-namespace:XF.Material.Forms.UI;assembly=XF.Material"
             mc:Ignorable="d"
             x:Class="App1.MainPage">

    <StackLayout>
        <!-- Place new controls here -->
        <ui:MaterialTextField x:Name="txt1"></ui:MaterialTextField>
    </StackLayout>

</ContentPage>

MainPage.xaml.cs

public MainPage()
        {
            InitializeComponent();
            new Thread(new ThreadStart(() =>
            {
                Thread.Sleep(2000);
                txt1.Text = "ofdfk";
            }));
        }

Configuration

Version: 1.x

Platform:

• 📱 iOS
• 🤖 Android
• 🏁 WPF
• 🌎 UWP
• 🍎 MacOS
• 📺 tvOS
• 🐒 Xamarin.Forms

[mr-rikhamba]

We recently started getting this issue, not sure why now all of a sudden, but based on forum search it might be related to a Xamar.iOS update. So with some guidance from other users in the forum I fixed it like this:

`       
private void SetTextFieldValues(List<MaterialSetter> controls)
{
Device.BeginInvokeOnMainThread(() =>
{
controls.ForEach(x =>
{
x.MaterialTextField.Focus();
Thread.Sleep(100);
x.MaterialTextField.SetBinding(MaterialTextField.TextProperty, new Binding($"BindingContext.{x.Value}", source: this));
//x.MaterialTextField.Unfocus();
});

controls.FirstOrDefault().MaterialTextField.Focus();
});
}
class MaterialSetter
{

public MaterialSetter(MaterialTextField materialTextField, string value)
{
MaterialTextField = materialTextField;
Value = value;
}

public MaterialTextField MaterialTextField { get; }
public string Value { get; }
}
`

And this is how I call it:
`            
SetTextFieldValues(new List<MaterialSetter>
{
new MaterialSetter(FullName, "Details.FullNames"),

});
`

[martijn00]

@pedroreglero can you make a PR with the fix?