DataGridBoundColumn.cs source code in C# .NET

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Code:

/ 4.0 / 4.0 / untmp / DEVDIV_TFS / Dev10 / Releases / RTMRel / wpf / src / Framework / System / Windows / Controls / DataGridBoundColumn.cs / 1305600 / DataGridBoundColumn.cs

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

using System; 
using System.Collections.ObjectModel; 
using System.ComponentModel;
using System.Diagnostics; 
using System.Windows;
using System.Windows.Data;
using System.Windows.Input;
 
namespace System.Windows.Controls
{ 
    ///  
    ///     A base class for specifying column definitions for certain standard
    ///     types that do not allow arbitrary templates. 
    /// 
    public abstract class DataGridBoundColumn : DataGridColumn
    {
        #region Constructors 

        static DataGridBoundColumn() 
        { 
            SortMemberPathProperty.OverrideMetadata(typeof(DataGridBoundColumn), new FrameworkPropertyMetadata(null, OnCoerceSortMemberPath));
        } 

        #endregion

        #region Binding 

        private static object OnCoerceSortMemberPath(DependencyObject d, object baseValue) 
        { 
            var column = (DataGridBoundColumn)d;
            var sortMemberPath = (string)baseValue; 

            if (string.IsNullOrEmpty(sortMemberPath))
            {
                var bindingSortMemberPath = DataGridHelper.GetPathFromBinding(column.Binding as Binding); 
                if (!string.IsNullOrEmpty(bindingSortMemberPath))
                { 
                    sortMemberPath = bindingSortMemberPath; 
                }
            } 

            return sortMemberPath;
        }
 
        /// 
        ///     The binding that will be applied to the generated element. 
        ///  
        /// 
        ///     This isn't a DP because if it were getting the value would evaluate the binding. 
        /// 
        public virtual BindingBase Binding
        {
            get 
            {
                return _binding; 
            } 

            set 
            {
                if (_binding != value)
                {
                    BindingBase oldBinding = _binding; 
                    _binding = value;
                    CoerceValue(IsReadOnlyProperty); 
                    CoerceValue(SortMemberPathProperty); 
                    OnBindingChanged(oldBinding, _binding);
                } 
            }
        }

        protected override bool OnCoerceIsReadOnly(bool baseValue) 
        {
            if (DataGridHelper.IsOneWay(_binding)) 
            { 
                return true;
            } 

            // only call the base if we dont want to force IsReadOnly true
            return base.OnCoerceIsReadOnly(baseValue);
        } 

        ///  
        ///     Called when Binding changes. 
        /// 
        ///  
        ///     Default implementation notifies the DataGrid and its subtree about the change.
        /// 
        /// The old binding.
        /// The new binding. 
        protected virtual void OnBindingChanged(BindingBase oldBinding, BindingBase newBinding)
        { 
            NotifyPropertyChanged("Binding"); 
        }
 
        /// 
        ///     Assigns the Binding to the desired property on the target object.
        /// 
        internal void ApplyBinding(DependencyObject target, DependencyProperty property) 
        {
            BindingBase binding = Binding; 
            if (binding != null) 
            {
                BindingOperations.SetBinding(target, property, binding); 
            }
            else
            {
                BindingOperations.ClearBinding(target, property); 
            }
        } 
 
        #endregion
 
        #region Styling

        /// 
        ///     A style that is applied to the generated element when not editing. 
        ///     The TargetType of the style depends on the derived column class.
        ///  
        public Style ElementStyle 
        {
            get { return (Style)GetValue(ElementStyleProperty); } 
            set { SetValue(ElementStyleProperty, value); }
        }

        ///  
        ///     The DependencyProperty for the ElementStyle property.
        ///  
        public static readonly DependencyProperty ElementStyleProperty = 
            DependencyProperty.Register(
                "ElementStyle", 
                typeof(Style),
                typeof(DataGridBoundColumn),
                new FrameworkPropertyMetadata(null, new PropertyChangedCallback(DataGridColumn.NotifyPropertyChangeForRefreshContent)));
 
        /// 
        ///     A style that is applied to the generated element when editing. 
        ///     The TargetType of the style depends on the derived column class. 
        /// 
        public Style EditingElementStyle 
        {
            get { return (Style)GetValue(EditingElementStyleProperty); }
            set { SetValue(EditingElementStyleProperty, value); }
        } 

        ///  
        ///     The DependencyProperty for the EditingElementStyle property. 
        /// 
        public static readonly DependencyProperty EditingElementStyleProperty = 
            DependencyProperty.Register(
                "EditingElementStyle",
                typeof(Style),
                typeof(DataGridBoundColumn), 
                new FrameworkPropertyMetadata(null, new PropertyChangedCallback(DataGridColumn.NotifyPropertyChangeForRefreshContent)));
 
        ///  
        ///     Assigns the ElementStyle to the desired property on the given element.
        ///  
        internal void ApplyStyle(bool isEditing, bool defaultToElementStyle, FrameworkElement element)
        {
            Style style = PickStyle(isEditing, defaultToElementStyle);
            if (style != null) 
            {
                element.Style = style; 
            } 
        }
 
        private Style PickStyle(bool isEditing, bool defaultToElementStyle)
        {
            Style style = isEditing ? EditingElementStyle : ElementStyle;
            if (isEditing && defaultToElementStyle && (style == null)) 
            {
                style = ElementStyle; 
            } 

            return style; 
        }

        #endregion
 
        #region Clipboard Copy/Paste
 
        ///  
        /// If base ClipboardContentBinding is not set we use Binding.
        ///  
        public override BindingBase ClipboardContentBinding
        {
            get
            { 
                return base.ClipboardContentBinding ?? Binding;
            } 
 
            set
            { 
                base.ClipboardContentBinding = value;
            }
        }
 
        #endregion
 
        #region Property Changed Handler 

        ///  
        /// Override which rebuilds the cell's visual tree for Binding change
        /// 
        /// 
        ///  
        protected internal override void RefreshCellContent(FrameworkElement element, string propertyName)
        { 
            DataGridCell cell = element as DataGridCell; 
            if (cell != null)
            { 
                bool isCellEditing = cell.IsEditing;
                if ((string.Compare(propertyName, "Binding", StringComparison.Ordinal) == 0) ||
                    (string.Compare(propertyName, "ElementStyle", StringComparison.Ordinal) == 0 && !isCellEditing) ||
                    (string.Compare(propertyName, "EditingElementStyle", StringComparison.Ordinal) == 0 && isCellEditing)) 
                {
                    cell.BuildVisualTree(); 
                    return; 
                }
            } 

            base.RefreshCellContent(element, propertyName);
        }
 
        #endregion
 
        #region Data 

        private BindingBase _binding; 

        #endregion
    }
} 

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


                        

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