ToolBarPanel.cs source code in C# .NET

Source code for the .NET framework in C#

                        
Code:

                         / DotNET / DotNET / 8.0 / untmp / WIN_WINDOWS / lh_tools_devdiv_wpf / Windows / wcp / Framework / System / Windows / Controls / Primitives / ToolBarPanel.cs / 1 / ToolBarPanel.cs
                        

                        
                            //---------------------------------------------------------------------------- 
//
// Copyright (C) Microsoft Corporation.  All rights reserved.
//
//--------------------------------------------------------------------------- 

using MS.Internal; 
using MS.Internal.KnownBoxes; 
using MS.Utility;
 
using System;
using System.Collections;
using System.Collections.Generic;
using System.Collections.Specialized; 
using System.ComponentModel;
using System.Diagnostics; 
using System.Windows.Controls.Primitives; 
using System.Windows.Data;
using System.Windows.Media; 
using System.Windows.Threading;

namespace System.Windows.Controls.Primitives
{ 
    /// 
    /// ToolBarPanel is used to arrange children within the ToolBar. It is used in the ToolBar style as items host. 
    ///  
    public class ToolBarPanel : StackPanel
    { 
        //-------------------------------------------------------------------
        //
        //  Constructors
        // 
        //-------------------------------------------------------------------
 
        #region Constructors 

        ///  
        /// Default constructor.
        /// 
        public ToolBarPanel()
        { 
        }
 
        #endregion Constructors 

        #region Override methods 

        /// 
        ///   Derived class must implement to support Visual children. The method must return
        ///    the child at the specified index. Index must be between 0 and GetVisualChildrenCount-1. 
        ///
        ///    By default a Visual does not have any children. 
        /// 
        ///  Remark:
        ///       Need to lock down Visual tree during the callbacks. 
        ///       During this virtual call it is not valid to modify the Visual tree.
        /// 
        protected override Visual GetVisualChild(int index)
        { 
            if(index < 0 || index >= VisualChildrenCount)
            { 
                throw new ArgumentOutOfRangeException("index", index, SR.Get(SRID.Visual_ArgumentOutOfRange)); 
            }
 
            return _uiElementCollection != null ? _uiElementCollection[index] : base.GetVisualChild(index);
        }

        ///  
        ///  Derived classes override this property to enable the Visual code to enumerate
        ///  the Visual children. Derived classes need to return the number of children 
        ///  from this method. 
        ///
        ///    By default a Visual does not have any children. 
        ///
        ///  Remark: During this virtual method the Visual tree must not be modified.
        /// 
        protected override int VisualChildrenCount 
        {
            get 
            { 
                return _uiElementCollection != null ? _uiElementCollection.Count : base.VisualChildrenCount;
            } 
        }


 
        /// 
        /// Measure the content and store the desired size of the content 
        ///  
        /// 
        ///  
        protected override Size MeasureOverride(Size constraint)
        {
            GenerateItems();
 
            if (IsItemsHost)
            { 
                // Clear the current visual collection 
                _uiElementCollection.Clear();
                // Clear the ToolBarOverflowPanel collection 
                ToolBarOverflowPanel tbop = ToolBarOverflowPanel;
                if (tbop != null)
                    tbop.Children.Clear();
 
                ToolBar toolBar = ToolBar;
 
                bool calcMinSizeMode = !toolBar.IsValidMinLength; 
                bool calcMaxSizeMode = !calcMinSizeMode && !toolBar.IsValidMaxLength;
 
                for (int i = 0; i < _generatedItemsCollection.Count; i++)
                {
                    UIElement uiElement = _generatedItemsCollection[i];
                    bool addElement = false; 
                    OverflowMode overflowMode = ToolBar.GetOverflowMode(uiElement);
 
                    // In case we measure minimum toolbar size - add only Never items 
                    if (calcMinSizeMode)
                    { 
                        addElement = overflowMode == OverflowMode.Never;
                    }
                    // In case we measure maximum toolbar size - add Never and AsNeeded items
                    else if (calcMaxSizeMode) 
                    {
                        addElement = overflowMode != OverflowMode.Always; 
                    } 
                    else // place only the items that fit
                    { 
                        // For now we add all items different from OverflowMode.Always
                        // then we measure them we remove those don't fit
                        addElement = overflowMode != OverflowMode.Always;
                    } 

                    // place in the main panel (this) 
                    if (addElement) 
                    {
                        _uiElementCollection.Add(uiElement); 
                        ToolBar.SetIsOverflowItem(uiElement, BooleanBoxes.FalseBox);
                    }
                    // place in the overflow panel (ToolBarOverflowPanel)
                    else 
                    {
                        // We only generate the items but they are not attached to the visual tree at this point 
                        // When overflow panel measures it adds all items which set this property: 
                        ToolBar.SetIsOverflowItem(uiElement, BooleanBoxes.TrueBox);
                    } 
                }
            }

            UIElementCollection children = _uiElementCollection; 
            Size stackDesiredSize = new Size();
            Size layoutSlotSize = constraint; 
            bool fHorizontal = (Orientation == Orientation.Horizontal); 
            double logicalAvailableWidth, logicalDesiredWidth;
 
            //
            // Initialize child sizing and iterator data
            // Allow children as much size as they want along the stack.
            // 
            if (fHorizontal)
            { 
                layoutSlotSize.Width = Double.PositiveInfinity; 
                logicalAvailableWidth = constraint.Width;
            } 
            else
            {
                layoutSlotSize.Height = Double.PositiveInfinity;
                logicalAvailableWidth = constraint.Height; 
            }
 
            // 
            //  Iterate through children.
            // 
            for (int i = 0, count = children.Count; i < count; ++i)
            {
                // Get next child.
                UIElement child = (UIElement)children[i]; 

                // Measure the child. 
                child.Measure(layoutSlotSize); 
                Size childDesiredSize = child.DesiredSize;
 
                // Accumulate child size.
                if (fHorizontal)
                {
                    stackDesiredSize.Width += childDesiredSize.Width; 
                    stackDesiredSize.Height = Math.Max(stackDesiredSize.Height, childDesiredSize.Height);
                } 
                else 
                {
                    stackDesiredSize.Width = Math.Max(stackDesiredSize.Width, childDesiredSize.Width); 
                    stackDesiredSize.Height += childDesiredSize.Height;
                }

            } 

            logicalDesiredWidth = fHorizontal ? stackDesiredSize.Width : stackDesiredSize.Height; 
 
            // After we measure all the children - if they don't fit within constraint size
            // - we need to remove AsNeeded items from the end of the collection 
            if (logicalDesiredWidth > logicalAvailableWidth)
            {
                for (int i = children.Count - 1; i >= 0; i--)
                { 
                    UIElement uiElement = (UIElement)children[i];
                    OverflowMode overflowMode = ToolBar.GetOverflowMode(uiElement); 
                    if (overflowMode == OverflowMode.AsNeeded) 
                    {
                        logicalDesiredWidth -= fHorizontal ? uiElement.DesiredSize.Width : uiElement.DesiredSize.Height; 
                        ToolBar.SetIsOverflowItem(uiElement, BooleanBoxes.TrueBox); // Marked for overflow
                        children.Remove(uiElement);

                        // If the rest of the items fit - exit the loop 
                        if (logicalDesiredWidth <= logicalAvailableWidth)
                            break; 
                    } 
                }
                logicalDesiredWidth = Math.Max(logicalDesiredWidth, 0d); 

                if (fHorizontal)
                {
                    stackDesiredSize.Width = logicalDesiredWidth; 
                }
                else 
                { 
                    stackDesiredSize.Height = logicalDesiredWidth;
                } 

            }

            // Update ToolBar.HasOverflowItemsProperty depend on number of overflow children 
            ToolBar tb = ToolBar;
            if (tb != null) 
            { 
                tb.SetValue(ToolBar.HasOverflowItemsPropertyKey, tb.Items.Count > children.Count);
            } 

            return stackDesiredSize;
        }
 
        /// 
        /// Content arrangement. 
        ///  
        /// Arrange size
        protected override Size ArrangeOverride(Size arrangeSize) 
        {
            UIElementCollection children = _uiElementCollection;
            bool fHorizontal = (Orientation == Orientation.Horizontal);
            Rect rcChild = new Rect(arrangeSize); 
            double previousChildSize = 0.0d;
 
            // 
            // Arrange and Position Children.
            // 
            for (int i = 0, count = children.Count; i < count; ++i)
            {
                UIElement child = (UIElement)children[i];
 
                if (fHorizontal)
                { 
                    rcChild.X += previousChildSize; 
                    previousChildSize = child.DesiredSize.Width;
                    rcChild.Width = previousChildSize; 
                    rcChild.Height = Math.Max(arrangeSize.Height, child.DesiredSize.Height);
                }
                else
                { 
                    rcChild.Y += previousChildSize;
                    previousChildSize = child.DesiredSize.Height; 
                    rcChild.Height = previousChildSize; 
                    rcChild.Width = Math.Max(arrangeSize.Width, child.DesiredSize.Width);
                } 

                child.Arrange(rcChild);
            }
 
            return arrangeSize;
        } 
 
        /// 
        /// ToolBarPanel sets bindings a on its Orientation property to its TemplatedParent if the 
        /// property is not already set.
        /// 
        internal override void OnPreApplyTemplate()
        { 
            base.OnPreApplyTemplate();
 
            if (TemplatedParent is ToolBar && !HasNonDefaultValue(OrientationProperty)) 
            {
                Binding binding = new Binding(); 
                binding.RelativeSource = RelativeSource.TemplatedParent;
                binding.Path = new PropertyPath(ToolBar.OrientationProperty);
                SetBinding(OrientationProperty, binding);
            } 
        }
 
        #endregion Override methods 

        // ItemsControl needs to access this collection for removing children 
        internal UIElementCollection UIElementCollection
        {
            get
            { 
                if (_uiElementCollection == null)
                { 
                    GenerateItems(); 
                }
                return _uiElementCollection; 
            }
        }

        #region private implementation 
        private void OnItemsChanged(object sender, ItemsChangedEventArgs args)
        { 
            switch (args.Action) 
            {
                case NotifyCollectionChangedAction.Add: 
                case NotifyCollectionChangedAction.Remove:
                case NotifyCollectionChangedAction.Reset:
                    _childrenGenerated = false;
                    GenerateItems(); 
                    break;
            } 
 
            InvalidateMeasure();
        } 

        // Items generation is executed when we call this method for the first time
        // or if items collection changes
        // All generated items are cached in _generatedItemsCollection 
        private void GenerateItems()
        { 
            // If items have been generated already 
            if (_childrenGenerated)
                return; 

            ToolBar toolBar = ToolBar;
            if (IsItemsHost && toolBar != null)
            { 
                if (_itemUIGenerator == null)
                { 
                    _itemUIGenerator = ((IItemContainerGenerator)toolBar.ItemContainerGenerator).GetItemContainerGeneratorForPanel(this); 
                    _itemUIGenerator.ItemsChanged += new ItemsChangedEventHandler(OnItemsChanged);
                } 
                IItemContainerGenerator generator = (IItemContainerGenerator)_itemUIGenerator;
                generator.RemoveAll();

                if (_uiElementCollection == null) 
                    _uiElementCollection = CreateUIElementCollection(null);
                else 
                    _uiElementCollection.Clear(); 

                GeneratedItemsCollection.Clear(); 

                // Clear the ToolBarOverflowPanel collection
                ToolBarOverflowPanel tbop = ToolBarOverflowPanel;
                if (tbop != null) 
                    tbop.Children.Clear();
 
                // Generate all items and keep them in _generatedItemsCollection 
                using (generator.StartAt(new GeneratorPosition(-1, 0), GeneratorDirection.Forward))
                { 
                    UIElement uiElement;
                    while ((uiElement = generator.GenerateNext() as UIElement) != null)
                    {
                        _generatedItemsCollection.Add(uiElement); 
                        _uiElementCollection.Add(uiElement);
                        ToolBar.SetIsOverflowItem(uiElement, BooleanBoxes.FalseBox); 
                        generator.PrepareItemContainer(uiElement); 
                    }
                } 

                _childrenGenerated = true;

            } 
            else
            { 
                _uiElementCollection = InternalChildren; 
            }
        } 

        private ToolBar ToolBar
        {
            get { return TemplatedParent as ToolBar; } 
        }
 
        private ToolBarOverflowPanel ToolBarOverflowPanel 
        {
            get 
            {
                ToolBar tb = ToolBar;
                return tb == null ? null : tb.ToolBarOverflowPanel;
            } 
        }
 
        internal List GeneratedItemsCollection 
        {
            get 
            {
                if (_generatedItemsCollection == null)
                    _generatedItemsCollection = new List(5);
                return _generatedItemsCollection; 
            }
 
        } 

        #endregion private implementation 

        #region private data
        private List _generatedItemsCollection;
        private UIElementCollection _uiElementCollection; 
        private ItemContainerGenerator _itemUIGenerator;
        private bool _childrenGenerated; 
        #endregion private data 

    } 
}


// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.

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