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Source/Engine/UI/GUI/Panels/VerticalPanel.cs

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+// Copyright (c) 2012-2020 Wojciech Figat. All rights reserved.
+
+namespace FlaxEngine.GUI
+{
+    /// <summary>
+    /// This panel arranges child controls vertically.
+    /// </summary>
+    /// <seealso cref="FlaxEngine.GUI.PanelWithMargins" />
+    public class VerticalPanel : PanelWithMargins
+    {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="VerticalPanel"/> class.
+        /// </summary>
+        public VerticalPanel()
+        {
+        }
+
+        /// <inheritdoc />
+        protected override void PerformLayoutBeforeChildren()
+        {
+            base.PerformLayoutBeforeChildren();
+
+            // Pre-set width of all controls
+            float w = Width - _margin.Width;
+            for (int i = 0; i < _children.Count; i++)
+            {
+                Control c = _children[i];
+                if (c.Visible)
+                {
+                    c.Width = w;
+                }
+            }
+        }
+
+        /// <inheritdoc />
+        protected override void PerformLayoutAfterChildren()
+        {
+            // Sort controls from top to bottom
+            float y = _margin.Top;
+            float w = Width - _margin.Width;
+            bool hasAnyItem = false;
+            for (int i = 0; i < _children.Count; i++)
+            {
+                Control c = _children[i];
+                if (c.Visible)
+                {
+                    var h = c.Height;
+                    c.Bounds = new Rectangle(_margin.Left + _offset.X, y + _offset.Y, w, h);
+                    y = c.Bottom + _spacing;
+                    hasAnyItem = true;
+                }
+            }
+            if (hasAnyItem)
+                y -= _spacing;
+            y += _margin.Bottom;
+
+            // Update size
+            if (_autoSize)
+                Height = y;
+        }
+    }
+}