AdornerDecorator.cs source code in C# .NET

Source code for the .NET framework in C#

                        

Code:

/ 4.0 / 4.0 / untmp / DEVDIV_TFS / Dev10 / Releases / RTMRel / wpf / src / Framework / System / Windows / Documents / AdornerDecorator.cs / 1305600 / AdornerDecorator.cs

                            //---------------------------------------------------------------------------- 
//
// 
//    Copyright (C) Microsoft Corporation.  All rights reserved.
//  
//
// 
// Description: 
//              AdornerDecorator class.
//              See spec at: http://avalon/uis/Specs/AdornerLayer%20Spec.htm 
//
// History:
//  1/29/2004 psarrett:  Created
// 
//---------------------------------------------------------------------------
using System; 
using System.Collections; 
using System.Windows;
using System.Windows.Controls; 
using System.Windows.Media;
using System.Windows.Threading;

namespace System.Windows.Documents 
{
 
    ///  
    /// This AdornerDecorator does not hookup its child in the logical tree. It's being
    /// used by PopupRoot and FixedDocument. 
    /// 
    internal class NonLogicalAdornerDecorator : AdornerDecorator
    {
        public override UIElement Child 
        {
            get 
            { 
                return IntChild;
            } 
            set
            {
                if (IntChild != value)
                { 
                    this.RemoveVisualChild(IntChild);
                    this.RemoveVisualChild(AdornerLayer); 
                    IntChild = value; 
                    if(value != null)
                    { 
                        this.AddVisualChild(value);
                        this.AddVisualChild(AdornerLayer);
                    }
 
                    InvalidateMeasure();
                } 
            } 
        }
    } 


    /// 
    /// Object which allows elements beneath it in the visual tree to be adorned. 
    /// AdornerDecorator has two children.
    /// The first child is the parent of the rest of the visual tree below the AdornerDecorator. 
    /// The second child is the AdornerLayer on which adorners are rendered. 
    ///
    /// AdornerDecorator is intended to be used as part of an object's Style. 
    /// 
    public class AdornerDecorator : Decorator
    {
        //----------------------------------------------------- 
        //
        //  Constructors 
        // 
        //-----------------------------------------------------
 
        #region Constructors

        /// 
        /// Constructor 
        /// 
        public AdornerDecorator() : base() 
        { 
            _adornerLayer = new AdornerLayer();
        } 

        #endregion Constructors

        //------------------------------------------------------ 
        //
        //  Public Methods 
        // 
        //-----------------------------------------------------
 
        //------------------------------------------------------
        //
        //  Public Properties
        // 
        //------------------------------------------------------
 
        #region Public Properties 

        ///  
        /// AdornerLayer on which adorners are rendered.
        /// 
        public AdornerLayer AdornerLayer
        { 
            get
            { 
                return _adornerLayer; 
            }
        } 

        #endregion Public Properties

        //----------------------------------------------------- 
        //
        //  Protected Methods 
        // 
        //------------------------------------------------------
 
        #region Protected Methods

        /// 
        /// Measurement override. Implement your size-to-content logic here. 
        /// 
        ///  
        /// Sizing constraint. 
        /// 
        protected override Size MeasureOverride(Size constraint) 
        {
                Size desiredSize = base.MeasureOverride(constraint);
                if (VisualTreeHelper.GetParent(_adornerLayer) != null)
                { 
                    // We don't really care about the size of the AdornerLayer-- we'll
                    // always just make the AdornerDecorator the full desiredSize.  But 
                    // we need to measure it anyway, to make sure Adorners render. 
                    _adornerLayer.Measure(constraint);
                } 
                return desiredSize;
        }

        ///  
        /// Override for 
        ///  
        /// The size reserved for this element by the parent 
        /// The actual ink area of the element, typically the same as finalSize
        protected override Size ArrangeOverride(Size finalSize) 
        {
                Size inkSize = base.ArrangeOverride(finalSize);

                if (VisualTreeHelper.GetParent(_adornerLayer) != null) 
                {
                    _adornerLayer.Arrange(new Rect(finalSize)); 
                } 

                return (inkSize); 
        }


        ///  
        /// Gets or sets the child of the AdornerDecorator.
        ///  
        public override UIElement Child 
        {
            get 
            {
                return base.Child;
            }
            set 
            {
                Visual old = base.Child; 
 
                if (old == value)
                { 
                    return;
                }

                if (value == null) 
                {
                    base.Child = null; 
                    RemoveVisualChild(_adornerLayer); 
                }
                else 
                {
                    base.Child = value;
                    if (null == old)
                    { 
                        AddVisualChild(_adornerLayer);
                    } 
                } 
            }
        } 

        /// 
        /// Returns the Visual children count.
        ///  
        protected override int VisualChildrenCount
        { 
            get 
            {
                if (base.Child != null) 
                {
                    return 2; // One for the child and one for the adorner layer.
                }
                else 
                {
                    return 0; 
                } 
            }
        } 

        /// 
        /// Returns the child at the specified index.
        ///  
        protected override Visual GetVisualChild(int index)
        { 
            if (base.Child == null) 
            {
                throw new ArgumentOutOfRangeException("index", index, SR.Get(SRID.Visual_ArgumentOutOfRange)); 
            }
            else
            {
                switch (index) 
                {
                    case 0: 
                        return base.Child; 

                    case 1: 
                        return _adornerLayer;

                    default:
                        throw new ArgumentOutOfRangeException("index", index, SR.Get(SRID.Visual_ArgumentOutOfRange)); 
                }
            } 
        } 

        #endregion Protected Methods 

        //-----------------------------------------------------
        //
        //  Private Members 
        //
        //----------------------------------------------------- 
 
        #region Private Members
 
        //
        //  This property
        //  1. Finds the correct initial size for the _effectiveValues store on the current DependencyObject
        //  2. This is a performance optimization 
        //
        internal override int EffectiveValuesInitialSize 
        { 
            get { return 6; }
        } 

        readonly AdornerLayer _adornerLayer;

        #endregion Private Members 

    } 
} 

 



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

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