Sicherung

FSI.Lib/NLogViewer/Extensions/DependencyObjectExtensions.cs

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+using System.Collections.Generic;
+using System.Windows;
+using System.Windows.Media;
+
+namespace DJ.Extensions
+{
+    public static class DependencyObjectExtensions
+    {
+        /// <summary>
+        /// Analyzes both visual and logical tree in order to find all elements of a given
+        /// type that are descendants of the <paramref name="source"/> item.
+        /// </summary>
+        /// <typeparam name="T">The type of the queried items.</typeparam>
+        /// <param name="source">The root element that marks the source of the search. If the
+        /// source is already of the requested type, it will not be included in the result.</param>
+        /// <param name="uid">The UID of the <see cref="UIElement"/></param>
+        /// <returns>All descendants of <paramref name="source"/> that match the requested type.</returns>
+        public static T FindChildByUid<T>(this DependencyObject source, string uid) where T : UIElement
+        {
+            if (source != null)
+            {
+                var childs = GetChildObjects(source);
+                foreach (DependencyObject child in childs)
+                {
+                    //analyze if children match the requested type
+                    if (child != null && child is T dependencyObject && dependencyObject.Uid.Equals(uid))
+                    {
+                        return dependencyObject;
+                    }
+                    
+                    var descendant = FindChildByUid<T>(child, uid);
+                    if (descendant != null)
+                        return descendant;
+                }
+            }
+
+            return null;
+        }
+        
+        /// <summary>
+        /// This method is an alternative to WPF's
+        /// <see cref="VisualTreeHelper.GetChild"/> method, which also
+        /// supports content elements. Keep in mind that for content elements,
+        /// this method falls back to the logical tree of the element.
+        /// </summary>
+        /// <param name="parent">The item to be processed.</param>
+        /// <returns>The submitted item's child elements, if available.</returns>
+        public static IEnumerable<DependencyObject> GetChildObjects(this DependencyObject parent)
+        {
+            if (parent == null) yield break;
+
+            if (parent is ContentElement || parent is FrameworkElement)
+            {
+                //use the logical tree for content / framework elements
+                foreach (object obj in LogicalTreeHelper.GetChildren(parent))
+                {
+                    var depObj = obj as DependencyObject;
+                    if (depObj != null) yield return (DependencyObject) obj;
+                }
+            }
+            else
+            {
+                //use the visual tree per default
+                int count = VisualTreeHelper.GetChildrenCount(parent);
+                for (int i = 0; i < count; i++)
+                {
+                    yield return VisualTreeHelper.GetChild(parent, i);
+                }
+            }
+        }
+    }
+}