| File: System\Windows\Automation\ItemContainerPattern.cs | Web Access |
| Project: src\wpf\src\Microsoft.DotNet.Wpf\src\UIAutomation\UIAutomationClient\UIAutomationClient.csproj (UIAutomationClient) |
// Licensed to the .NET Foundation under one or more agreements. // The .NET Foundation licenses this file to you under the MIT license. // Description: Client-side wrapper for ItemContainer Pattern using MS.Internal.Automation; using System.Globalization; namespace System.Windows.Automation { /// <summary> /// Represents Containers that maintains items and support item look up by propety value. /// </summary> #if (INTERNAL_COMPILE) internal class ItemContainerPattern: BasePattern #else public class ItemContainerPattern: BasePattern #endif { //------------------------------------------------------ // // Constructors // //------------------------------------------------------ #region Constructors private ItemContainerPattern(AutomationElement el, SafePatternHandle hPattern) : base(el, hPattern) { _hPattern = hPattern; } #endregion Constructors //------------------------------------------------------ // // Public Constants / Readonly Fields // //------------------------------------------------------ #region Public Constants and Readonly Fields /// <summary>ItemContainer pattern</summary> public static readonly AutomationPattern Pattern = ItemContainerPatternIdentifiers.Pattern; #endregion Public Constants and Readonly Fields //------------------------------------------------------ // // Public Methods // //------------------------------------------------------ #region Public Methods /// <summary> /// Find item by specified property/value. It will return /// placeholder which depending upon it's virtualization state may /// or may not have the information of the complete peer/Wrapper. /// /// Throws ArgumentException if the property requested is not one that the /// container supports searching over. Supports Name property, AutomationId, /// IsSelected and ControlType. /// /// This method is expected to be relatively slow, since it may need to /// traverse multiple objects in order to find a matching one. /// When used in a loop to return multiple items, no specific order is /// defined so long as each item is returned only once (ie. loop should /// terminate). This method is also item-centric, not UI-centric, so items /// with multiple UI representations need only be returned once. /// /// A special propertyId of 0 means ‘match all items’. This can be used /// with startAfter=NULL to get the first item, and then to get successive /// items. /// </summary> /// <param name="startAfter">this represents the item after which the container wants to begin search</param> /// <param name="property">corresponds to property for whose value it want to search over.</param> /// <param name="value">value to be searched for, for specified property</param> /// <returns>The first item which matches the searched criterion, if no item matches, it returns null </returns> public AutomationElement FindItemByProperty(AutomationElement startAfter, AutomationProperty property, object value) { SafeNodeHandle hNode; // Invalidate the "value" passed against the "property" before passing it to UIACore, Don't invalidate if search is being done for "null" property // FindItemByProperty supports find for null property. if (property != null) { value = PropertyValueValidateAndMap(property, value); } if (startAfter != null) { if (property != null) hNode = UiaCoreApi.ItemContainerPattern_FindItemByProperty(_hPattern, startAfter.RawNode, property.Id, value); else hNode = UiaCoreApi.ItemContainerPattern_FindItemByProperty(_hPattern, startAfter.RawNode, 0, null); } else { if (property != null) hNode = UiaCoreApi.ItemContainerPattern_FindItemByProperty(_hPattern, new SafeNodeHandle(), property.Id, value); else hNode = UiaCoreApi.ItemContainerPattern_FindItemByProperty(_hPattern, new SafeNodeHandle(), 0, null); } AutomationElement wrappedElement = AutomationElement.Wrap(hNode); return wrappedElement; } #endregion Public Methods //------------------------------------------------------ // // Private Methods // //------------------------------------------------------ #region Private Methods private object PropertyValueValidateAndMap(AutomationProperty property, object value) { AutomationPropertyInfo info; if (!Schema.GetPropertyInfo(property, out info)) { throw new ArgumentException(SR.UnsupportedProperty); } // Check type is appropriate: NotSupported is allowed against any property, // null is allowed for any reference type (ie not for value types), otherwise // type must be assignable from expected type. Type expectedType = info.Type; if (value != AutomationElement.NotSupported && ((value == null && expectedType.IsValueType) || (value != null && !expectedType.IsAssignableFrom(value.GetType())))) { throw new ArgumentException(SR.Format(SR.PropertyConditionIncorrectType, property.ProgrammaticName, expectedType.Name)); } // Some types are handled differently in managed vs unmanaged - handle those here... if (value is AutomationElement) { // If this is a comparison against a Raw/LogicalElement, // save the runtime ID instead of the element so that we // can take it cross-proc if needed. value = ((AutomationElement)value).GetRuntimeId(); } else if (value is ControlType) { // If this is a control type, use the ID, not the CLR object value = ((ControlType)value).Id; } else if (value is Rect rc) { value = new double[] { rc.Left, rc.Top, rc.Width, rc.Height }; } else if (value is Point pt) { value = new double[] { pt.X, pt.Y }; } else if (value is CultureInfo) { value = ((CultureInfo)value).LCID; } return value; } #endregion Internal Methods //------------------------------------------------------ // // Internal Methods // //------------------------------------------------------ #region Internal Methods internal static object Wrap(AutomationElement el, SafePatternHandle hPattern, bool cached) { return new ItemContainerPattern(el, hPattern); } #endregion Internal Methods //------------------------------------------------------ // // Private Fields // //------------------------------------------------------ #region Private Fields private SafePatternHandle _hPattern; #endregion Private Fields } }