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// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
// Description: Client-side wrapper for Selection Pattern
using MS.Internal.Automation;
namespace System.Windows.Automation
{
/// <summary>
/// Class representing containers that manage selection.
/// </summary>
#if (INTERNAL_COMPILE)
internal class SelectionPattern: BasePattern
#else
public class SelectionPattern: BasePattern
#endif
{
//------------------------------------------------------
//
// Constructors
//
//------------------------------------------------------
#region Constructors
private SelectionPattern(AutomationElement el, SafePatternHandle hPattern, bool cached)
: base(el, hPattern)
{
_hPattern = hPattern;
_cached = cached;
}
#endregion Constructors
//------------------------------------------------------
//
// Public Constants / Readonly Fields
//
//------------------------------------------------------
#region Public Constants and Readonly Fields
/// <summary>Selection pattern</summary>
public static readonly AutomationPattern Pattern = SelectionPatternIdentifiers.Pattern;
/// <summary>Get the currently selected elements</summary>
public static readonly AutomationProperty SelectionProperty = SelectionPatternIdentifiers.SelectionProperty;
/// <summary>Indicates whether the control allows more than one element to be selected</summary>
public static readonly AutomationProperty CanSelectMultipleProperty = SelectionPatternIdentifiers.CanSelectMultipleProperty;
/// <summary>Indicates whether the control requires at least one element to be selected</summary>
public static readonly AutomationProperty IsSelectionRequiredProperty = SelectionPatternIdentifiers.IsSelectionRequiredProperty;
/// <summary>
/// Event ID: SelectionInvalidated - indicates that selection changed in a selection conainer.
/// sourceElement refers to the selection container
/// </summary>
public static readonly AutomationEvent InvalidatedEvent = SelectionPatternIdentifiers.InvalidatedEvent;
#endregion Public Constants and Readonly Fields
//------------------------------------------------------
//
// Public Methods
//
//------------------------------------------------------
#region Public Methods
// No public methods
#endregion Public Methods
//------------------------------------------------------
//
// Public Properties
//
//------------------------------------------------------
#region Public Properties
/// <summary>
/// This member allows access to previously requested
/// cached properties for this element. The returned object
/// has accessors for each property defined for this pattern.
/// </summary>
/// <remarks>
/// Cached property values must have been previously requested
/// using a CacheRequest. If you try to access a cached
/// property that was not previously requested, an InvalidOperation
/// Exception will be thrown.
///
/// To get the value of a property at the current point in time,
/// access the property via the Current accessor instead of
/// Cached.
/// </remarks>
public SelectionPatternInformation Cached
{
get
{
Misc.ValidateCached(_cached);
return new SelectionPatternInformation(_el, true);
}
}
/// <summary>
/// This member allows access to current property values
/// for this element. The returned object has accessors for
/// each property defined for this pattern.
/// </summary>
/// <remarks>
/// This pattern must be from an AutomationElement with a
/// Full reference in order to get current values. If the
/// AutomationElement was obtained using AutomationElementMode.None,
/// then it contains only cached data, and attempting to get
/// the current value of any property will throw an InvalidOperationException.
///
/// To get the cached value of a property that was previously
/// specified using a CacheRequest, access the property via the
/// Cached accessor instead of Current.
/// </remarks>
public SelectionPatternInformation Current
{
get
{
Misc.ValidateCurrent(_hPattern);
return new SelectionPatternInformation(_el, false);
}
}
#endregion Public Properties
//------------------------------------------------------
//
// Internal Methods
//
//------------------------------------------------------
#region Internal Methods
internal static object Wrap(AutomationElement el, SafePatternHandle hPattern, bool cached)
{
return new SelectionPattern(el, hPattern, cached);
}
#endregion Internal Methods
//------------------------------------------------------
//
// Private Fields
//
//------------------------------------------------------
#region Private Fields
private SafePatternHandle _hPattern;
private bool _cached;
#endregion Private Fields
//------------------------------------------------------
//
// Nested Classes
//
//------------------------------------------------------
#region Nested Classes
/// <summary>
/// This class provides access to either Cached or Current
/// properties on a pattern via the pattern's .Cached or
/// .Current accessors.
/// </summary>
public struct SelectionPatternInformation
{
//------------------------------------------------------
//
// Constructors
//
//------------------------------------------------------
#region Constructors
internal SelectionPatternInformation(AutomationElement el, bool useCache)
{
_el = el;
_useCache = useCache;
}
#endregion Constructors
//------------------------------------------------------
//
// Public Methods
//
//------------------------------------------------------
#region Public Methods
/// <summary>
/// Get the currently selected elements
/// </summary>
/// <returns>An AutomationElement array containing the currently selected elements</returns>
public AutomationElement[] GetSelection()
{
return (AutomationElement[])_el.GetPatternPropertyValue(SelectionProperty, _useCache);
}
#endregion Public Methods
//------------------------------------------------------
//
// Public Properties
//
//------------------------------------------------------
#region Public Properties
/// <summary>
/// Indicates whether the control allows more than one element to be selected
/// </summary>
/// <returns>Boolean indicating whether the control allows more than one element to be selected</returns>
/// <remarks>If this is false, then the control is a single-select ccntrol</remarks>
public bool CanSelectMultiple
{
get
{
return (bool)_el.GetPatternPropertyValue(CanSelectMultipleProperty, _useCache);
}
}
/// <summary>
/// Indicates whether the control requires at least one element to be selected
/// </summary>
/// <returns>Boolean indicating whether the control requires at least one element to be selected</returns>
/// <remarks>If this is false, then the control allows all elements to be unselected</remarks>
public bool IsSelectionRequired
{
get
{
return (bool)_el.GetPatternPropertyValue(IsSelectionRequiredProperty, _useCache);
}
}
#endregion Public Properties
//------------------------------------------------------
//
// Private Fields
//
//------------------------------------------------------
#region Private Fields
private AutomationElement _el; // AutomationElement that contains the cache or live reference
private bool _useCache; // true to use cache, false to use live reference to get current values
#endregion Private Fields
}
#endregion Nested Classes
}
}
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