整理一下项目文件

AIStudio.Wpf.DiagramDesigner/Helpers/ControlMouseLeftButtonDownCommandBehavior.cs

@@ -0,0 +1,184 @@
+using Microsoft.Xaml.Behaviors;
+using System;
+using System.Windows;
+using System.Windows.Input;
+
+namespace AIStudio.Wpf.DiagramDesigner
+{
+    public class ControlMouseLeftButtonDownCommandBehavior : Behavior<FrameworkElement>
+    {
+        #region Overrides
+        protected override void OnAttached()
+        {
+
+            base.OnAttached();
+            AssociatedObject.PreviewMouseLeftButtonDown += AssociatedObject_PreviewMouseLeftButtonDown;
+            EnableDisableElement();
+        }
+
+        protected override void OnDetaching()
+        {
+            AssociatedObject.PreviewMouseLeftButtonDown -= AssociatedObject_PreviewMouseLeftButtonDown;
+        }
+        #endregion
+
+        #region Private Methods
+        private void AssociatedObject_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
+        {
+            //Get the ItemsControl and then get the item, and check there
+            //is an actual item, as if we are using a ListView we may have clicked the
+            //headers which are not items
+            //ItemsControl listView = sender as ItemsControl;
+            //DependencyObject originalSender = e.OriginalSource as DependencyObject;
+            //if (listView == null || originalSender == null) return;
+
+            //DependencyObject container =
+            //    ItemsControl.ContainerFromElement
+            //    (sender as ItemsControl, e.OriginalSource as DependencyObject);
+
+            //if (container == null ||
+            //    container == DependencyProperty.UnsetValue) return;
+
+            //// found a container, now find the item.
+            //object activatedItem =
+            //    listView.ItemContainerGenerator.ItemFromContainer(container);
+
+            //if (activatedItem != null)
+            //{
+            //    Invoke(activatedItem, e);
+            //}
+
+            FrameworkElement control = sender as FrameworkElement;
+            DependencyObject originalSender = e.OriginalSource as DependencyObject;
+            if (control == null || originalSender == null) return;
+
+            Invoke(control, e);
+        }
+
+        private static void OnCommandChanged(ControlMouseLeftButtonDownCommandBehavior thisBehaviour,
+            DependencyPropertyChangedEventArgs e)
+        {
+            if (thisBehaviour == null)
+            {
+                return;
+            }
+
+            if (e.OldValue != null)
+            {
+                ((ICommand)e.OldValue).CanExecuteChanged -= thisBehaviour.OnCommandCanExecuteChanged;
+            }
+
+            ICommand command = (ICommand)e.NewValue;
+
+            if (command != null)
+            {
+                command.CanExecuteChanged += thisBehaviour.OnCommandCanExecuteChanged;
+            }
+
+            thisBehaviour.EnableDisableElement();
+        }
+
+        private bool IsAssociatedElementDisabled()
+        {
+            return AssociatedObject != null && !AssociatedObject.IsEnabled;
+        }
+
+        private void EnableDisableElement()
+        {
+            if (AssociatedObject == null || Command == null)
+            {
+                return;
+            }
+
+            AssociatedObject.IsEnabled = Command.CanExecute(this.CommandParameter);
+        }
+
+        private void OnCommandCanExecuteChanged(object sender, EventArgs e)
+        {
+            EnableDisableElement();
+        }
+
+        #endregion
+
+        #region Protected Methods
+        /// <param name="parameter">The EventArgs of the fired event.</param>
+        protected void Invoke(object clickedItem, MouseButtonEventArgs parameter)
+        {
+            if (IsAssociatedElementDisabled())
+            {
+                return;
+            }
+
+            ICommand command = Command;
+            if (command != null && command.CanExecute(CommandParameter))
+            {
+                command.Execute(new EventToCommandArgs(clickedItem, command,
+                    CommandParameter, (EventArgs)parameter));
+            }
+        }
+        #endregion
+
+        #region DPs
+
+        #region CommandParameter
+        /// <summary>
+        /// Identifies the <see cref="CommandParameter" /> dependency property
+        /// </summary>
+        public static readonly DependencyProperty CommandParameterProperty = DependencyProperty.Register(
+            "CommandParameter", typeof(object), typeof(ControlMouseLeftButtonDownCommandBehavior),
+            new PropertyMetadata(null,
+                (s, e) =>
+                {
+                    ControlMouseLeftButtonDownCommandBehavior sender = s as ControlMouseLeftButtonDownCommandBehavior;
+                    if (sender == null)
+                    {
+                        return;
+                    }
+
+                    if (sender.AssociatedObject == null)
+                    {
+                        return;
+                    }
+
+                    sender.EnableDisableElement();
+                }));
+
+
+        /// <summary>
+        /// Gets or sets an object that will be passed to the <see cref="Command" />
+        /// attached to this trigger. This is a DependencyProperty.
+        /// </summary>
+        public object CommandParameter
+        {
+            get { return (Object)GetValue(CommandParameterProperty); }
+            set { SetValue(CommandParameterProperty, value); }
+        }
+
+        #endregion
+
+        #region Command
+        /// <summary
+        /// >
+        /// Identifies the <see cref="Command" /> dependency property
+        /// </summary>
+        public static readonly DependencyProperty CommandProperty = DependencyProperty.Register(
+            "Command", typeof(ICommand), typeof(ControlMouseLeftButtonDownCommandBehavior),
+            new PropertyMetadata(null,
+                (s, e) => OnCommandChanged(s as ControlMouseLeftButtonDownCommandBehavior, e)));
+
+
+        /// <summary>
+        /// Gets or sets the ICommand that this trigger is bound to. This
+        /// is a DependencyProperty.
+        /// </summary>
+        public ICommand Command
+        {
+            get { return (ICommand)GetValue(CommandProperty); }
+            set { SetValue(CommandProperty, value); }
+        }
+        #endregion
+
+        #endregion
+
+    }
+}