[NUI] Introduce new binding style.

src/Tizen.NUI.Components/Controls/RecyclerView/Item/RecyclerViewItem.Internal.cs

@@ -227,6 +227,7 @@ protected override void OnEnabled(bool enabled)
         protected override void OnBindingContextChanged()
         {
             PropagateBindingContext(this);
+            base.OnBindingContextChanged();
         }
 
         private void PropagateBindingContext(View parent)

src/Tizen.NUI/src/devel/Binding/BindingExtensions.cs

@@ -0,0 +1,207 @@
+using System;
+using System.ComponentModel;
+using System.Reflection;
+using Tizen.NUI.BaseComponents;
+
+namespace Tizen.NUI.Binding
+{
+    /// <summary>
+    /// Provides extension methods for binding properties of a view model to a view.
+    /// </summary>
+    [EditorBrowsable(EditorBrowsableState.Never)]
+    public static class BindingExtensions
+    {
+        /// <summary>
+        /// Sets the binding for the specified view model property.
+        /// </summary>
+        /// <typeparam name="T">The type of the view model.</typeparam>
+        /// <typeparam name="TView">The type of the view.</typeparam>
+        /// <param name="view">The view to bind to.</param>
+        /// <param name="vm">The view model to bind from.</param>
+        /// <param name="set">The action to set the view property.</param>
+        /// <param name="path">The path of the view model property.</param>
+        /// <returns>The view.</returns>
+        public static TView SetBinding<T, TView>(this TView view, BindingSession<T> vm, Action<T, TView> set, string path) where TView : View
+        {
+            _ = view ?? throw new ArgumentNullException(nameof(view));
+
+            var setter = new Action<T>(vm =>
+            {
+                set.Invoke(vm, view);
+            });
+            vm.AddBinding(setter, path);
+            return view;
+        }
+
+        /// <summary>
+        /// Sets the binding for the specified view model property.
+        /// </summary>
+        /// <typeparam name="T">The type of the view model.</typeparam>
+        /// <param name="view">The view to bind to.</param>
+        /// <param name="vm">The view model to bind from.</param>
+        /// <param name="set">The action to set the view property.</param>
+        /// <param name="path">The path of the view model property.</param>
+        /// <returns>The view.</returns>
+        public static View SetBinding<T>(this View view, BindingSession<T> vm, Action<T> set, string path)
+        {
+            vm.AddBinding(set, path);
+            return view;
+        }
+
+        /// <summary>
+        /// Sets the binding for the specified view model property.
+        /// </summary>
+        /// <typeparam name="TViewModel">The type of the view model.</typeparam>
+        /// <param name="view">The view to bind to.</param>
+        /// <param name="session">The binding session.</param>
+        /// <param name="targetPath">The path of the view property.</param>
+        /// <param name="srcPath">The path of the view model property.</param>
+        /// <returns>The view.</returns>
+        public static View SetBinding<TViewModel>(this View view, BindingSession<TViewModel> session, string targetPath, string srcPath)
+        {
+            var setter = new Action<TViewModel>(model =>
+            {
+                if (view.Disposed)
+                {
+                    return;
+                }
+                var prop = view.GetType().GetProperty(targetPath, BindingFlags.Public | BindingFlags.Instance);
+                prop.SetValue(view, session.GetValue(srcPath));
+            });
+            session.AddBinding(setter, srcPath);
+            return view;
+        }
+
+        /// <summary>
+        /// Sets the binding for the specified view model property.
+        /// </summary>
+        /// <typeparam name="TView">The type of the view.</typeparam>
+        /// <typeparam name="TViewModel">The type of the view model.</typeparam>
+        /// <typeparam name="TProperty">The type of the view property.</typeparam>
+        /// <param name="view">The view to bind to.</param>
+        /// <param name="session">The binding session.</param>
+        /// <param name="property">The view property.</param>
+        /// <param name="path">The path of the view model property.</param>
+        /// <returns>The view.</returns>
+        public static TView SetBinding<TView, TViewModel, TProperty>(this TView view, BindingSession<TViewModel> session, BindingProperty<TView, TProperty> property, string path) where TView : View
+        {
+            var setter = new Action<TViewModel>(model =>
+            {
+                if (view.Disposed)
+                {
+                    return;
+                }
+
+                var value = session.GetValue(path);
+                // need to apply convertor if type was not mached
+                if (value != null && !typeof(TProperty).IsAssignableFrom(value.GetType()))
+                {
+                    // only string type convert with ToString()
+                    if (typeof(TProperty) == typeof(string))
+                    {
+                        value = value.ToString();
+                    }
+                    else
+                    {
+                        throw new InvalidCastException($"Cannot cast {value.GetType()} to {typeof(TProperty)}");
+                    }
+                }
+                property.Setter(view, (TProperty)value);
+            });
+            session.AddBinding(setter, path);
+            return view;
+        }
+
+        /// <summary>
+        /// Sets the two-way binding for the specified view model property.
+        /// </summary>
+        /// <typeparam name="TViewModel">The type of the view model.</typeparam>
+        /// <typeparam name="TProperty">The type of the view property.</typeparam>
+        /// <param name="view">The view to bind to.</param>
+        /// <param name="session">The binding session.</param>
+        /// <param name="property">The view property.</param>
+        /// <param name="path">The path of the view model property.</param>
+        /// <returns>The view.</returns>
+        public static View SetTwoWayBinding<TViewModel, TProperty>(this View view, BindingSession<TViewModel> session, TwoWayBindingProperty<View, TProperty> property, string path)
+        {
+            var regit = new Action<Action>(act =>
+            {
+                property.AddObserver(view, act);
+            });
+            var unregit = new Action<Action>(act =>
+            {
+                property.RemoveObserver(view, act);
+            });
+            var setter = new Action<TViewModel>(model =>
+            {
+                if (view.Disposed)
+                {
+                    return;
+                }
+                property.Setter(view, (TProperty)session.GetValue(path));
+            });
+            var getter = new Func<TProperty>(() => property.Getter(view));
+            session.AddTwoWayBinding(regit, unregit, setter, getter, path);
+            return view;
+        }
+
+        /// <summary>
+        /// Sets the two-way binding for the specified view model property.
+        /// </summary>
+        /// <typeparam name="TView">The type of the view.</typeparam>
+        /// <typeparam name="TViewModel">The type of the view model.</typeparam>
+        /// <typeparam name="TProperty">The type of the view property.</typeparam>
+        /// <param name="view">The to.</param>
+        /// <param name="session">The binding session.</param>
+        /// <param name="property">The view property.</param>
+        /// <param name="path">The path of the view model property.</param>
+        /// <returns>The view.</returns>
+        public static TView SetTwoWayBinding<TView, TViewModel, TProperty>(this TView view, BindingSession<TViewModel> session, TwoWayBindingProperty<TView, TProperty> property, string path) where TView : View
+        {
+            var regit = new Action<Action>(act =>
+            {
+                property.AddObserver(view, act);
+            });
+            var unregit = new Action<Action>(act =>
+            {
+                property.RemoveObserver(view, act);
+            });
+            var setter = new Action<TViewModel>(model =>
+            {
+                if (view.Disposed)
+                {
+                    return;
+                }
+                property.Setter(view, (TProperty)session.GetValue(path));
+            });
+            var getter = new Func<TProperty>(() => property.Getter(view));
+            session.AddTwoWayBinding(regit, unregit, setter, getter, path);
+            return view;
+        }
+
+        /// <summary>
+        /// Gets the binding session for the specified view.
+        /// </summary>
+        /// <typeparam name="TViewModel">The type of the view model.</typeparam>
+        /// <param name="view">The view.</param>
+        /// <returns>The binding session.</returns>
+        public static BindingSession<TViewModel> BindingSession<TViewModel>(this View view)
+        {
+            return view.GetAttached<BindingSession<TViewModel>>();
+        }
+
+        /// <summary>
+        /// Sets the binding session for the specified view.
+        /// </summary>
+        /// <typeparam name="T">The type of the view model.</typeparam>
+        /// <typeparam name="TViewModel">The type of the view.</typeparam>
+        /// <param name="view">The view.</param>
+        /// <param name="session">The binding session.</param>
+        /// <returns>The view.</returns>
+        public static T BindingSession<T, TViewModel>(this T view, BindingSession<TViewModel> session) where T : View
+        {
+            view.SetAttached(session);
+            return view;
+        }
+    }
+}

src/Tizen.NUI/src/devel/Binding/BindingProperty.cs

@@ -0,0 +1,19 @@
+using System;
+using System.ComponentModel;
+
+namespace Tizen.NUI.Binding
+{
+    /// <summary>
+    /// The BindingProperty class represents a binding property for a view.
+    /// </summary>
+    /// <typeparam name="TView">The type of the view.</typeparam>
+    /// <typeparam name="TValue">The type of the value.</typeparam>
+    [EditorBrowsable(EditorBrowsableState.Never)]
+    public class BindingProperty<TView, TValue>
+    {
+        /// <summary>
+        /// Gets or sets the setter action for the binding property.
+        /// </summary>
+        public Action<TView, TValue> Setter { get; set; }
+    }
+}