Xamarin.Forms.Core 1.0.0.0 1.1.0.0 1.2.0.0 1.3.0.0 1.4.0.0 1.5.0.0 2.0.0.0 System.Enum The direction of changes propagation for bindings. The following examples shows some BindingMode use cases. (Label.TextProperty, vm => vm.Name, mode: BindingMode.OneWay); viewmodel.Name = "John Doe"; Debug.WriteLine (label.Text); //prints "John Doe" label.Text = "Foo"; Debug.WriteLine (viewmodel.Name); //prints "John Doe" //BindingMode.TwoWay label = new Label (); label.BindingContext = viewmodel = new PersonViewModel (); label.SetBinding (Label.TextProperty, vm => vm.Name, mode: BindingMode.TwoWay); viewmodel.Name = "John Doe"; Debug.WriteLine (label.Text); //prints "John Doe" label.Text = "Foo"; Debug.WriteLine (viewmodel.Name); //prints "Foo" //BindingMode.OneWayToSource label = new Label (); label.BindingContext = viewmodel = new PersonViewModel (); label.SetBinding (Label.TextProperty, vm => vm.Name, mode: BindingMode.OneWayToSource); viewmodel.Name = "John Doe"; Debug.WriteLine (label.Text); //prints "" label.Text = "Foo"; Debug.WriteLine (viewmodel.Name); //prints "Foo" ]]> Field 1.0.0.0 1.1.0.0 1.2.0.0 1.3.0.0 1.4.0.0 1.5.0.0 2.0.0.0 Xamarin.Forms.BindingMode When used in Bindings, indicates that the Binding should use the . When used in BindableProperty declaration, defaults to BindingMode.OneWay. Field 1.0.0.0 1.1.0.0 1.2.0.0 1.3.0.0 1.4.0.0 1.5.0.0 2.0.0.0 Xamarin.Forms.BindingMode Indicates that the binding should only propagates changes from source (usually the View Model) to target (the BindableObject). This is the default mode for most BindableProperty values. Field 1.0.0.0 1.1.0.0 1.2.0.0 1.3.0.0 1.4.0.0 1.5.0.0 2.0.0.0 Xamarin.Forms.BindingMode Indicates that the binding should only propagates changes from target (the BindableObject) to source (usually the View Model). This is mainly used for read-only BindableProperty values. Field 1.0.0.0 1.1.0.0 1.2.0.0 1.3.0.0 1.4.0.0 1.5.0.0 2.0.0.0 Xamarin.Forms.BindingMode Indicates that the binding should propagates changes from source (usually the View Model) to target (the BindableObject) in both directions.