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Gents,
in short, I'm surprised how can I update GUI from another thread started by a Task? See below example.
Sure that is a fake Async implementation but ignore that now...
Question how that works well even I expected Exceptions as GUI updated not from the GUI thread?
So, could somebody confirm is it a good way, and what makes that work?
Thanks!

What I have tried:

the binding:

<textblock text="{Binding Name}">

the view:

class Person : INotifyPropertyChanged
    {
        private string _name;
        public void Run()
        {
            //do something long...
            Name = "karoly";
        }
        public string Name
        {
            get
            {
                return _name;
            }
            set
            {
                _name = value;
                OnPropertyChanged("Name");
            }
        }
        public event PropertyChangedEventHandler PropertyChanged;
        private void OnPropertyChanged(string propertyName)
        {
            if (PropertyChanged != null)
            {
                PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
            }
        }
    }


the application:


Person person;
       public MainWindow()
       {
           InitializeComponent();
           person= new Person();
           this.DataContext = person;
           person.Name = "unknown";

       }

       private async void RunButton_Click(object sender, RoutedEventArgs e)
       {
           Task t = new Task(person.Run);
           t.Start();
           await t;

       }
Posted
Updated 15-Feb-21 9:10am
Comments
[no name] 12-Feb-21 7:42am
   
I think this will answer your question, see accepted answer:
multithreading - WPF Databinding thread safety? - Stack Overflow[^]
Member 11704751 12-Feb-21 8:11am
   
thanks embarkadero
some comments really suggests that data automatically marshalled to GUI , but not for collcetions...
[no name] 12-Feb-21 10:07am
   

1 solution

as Embarkadero suggested , Microsoft say that supported by WPF:
Quote:
Accessing collections on non-UI Threads
WPF enables you to access and modify data collections on threads other than the one that created the collection. This enables you to use a background thread to receive data from an external source, such as a database, and display the data on the UI thread. By using another thread to modify the collection, your user interface remains responsive to user interaction.


Thanks Embarkadero!
   

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