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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.
using System.Drawing;
using Windows.Win32.System.Variant;
using Windows.Win32.UI.Accessibility;
namespace System.Windows.Forms;
public partial class TabPage
{
internal sealed class TabPageAccessibleObject : ControlAccessibleObject
{
public TabPageAccessibleObject(TabPage owningTabPage) : base(owningTabPage) { }
internal override Rectangle BoundingRectangle => this.IsOwnerHandleCreated(out TabPage? owner) ?
owner.GetPageRectangle() : Rectangle.Empty;
public override AccessibleStates State => SystemIAccessible.TryGetState(GetChildId());
internal override IRawElementProviderFragmentRoot.Interface? FragmentRoot => OwningTabControl?.AccessibilityObject;
private TabControl? OwningTabControl =>
this.TryGetOwnerAs(out TabPage? owningTabPage) ? owningTabPage.ParentInternal as TabControl : null;
public override AccessibleObject? GetChild(int index)
{
if (!this.IsOwnerHandleCreated(out TabPage? owningTabPage))
{
return null;
}
if (index < 0 || index > owningTabPage.Controls.Count - 1)
{
return null;
}
return owningTabPage.Controls[index].AccessibilityObject;
}
private protected override bool IsInternal => true;
public override int GetChildCount()
=> this.IsOwnerHandleCreated(out TabPage? owningTabPage) ? owningTabPage.Controls.Count : -1;
internal override IRawElementProviderFragment.Interface? FragmentNavigate(NavigateDirection direction)
{
if (!this.IsOwnerHandleCreated(out TabPage? _) || OwningTabControl is null)
{
return null;
}
return direction switch
{
NavigateDirection.NavigateDirection_Parent => OwningTabControl?.AccessibilityObject,
NavigateDirection.NavigateDirection_NextSibling => GetNextSibling(),
NavigateDirection.NavigateDirection_PreviousSibling => null,
_ => base.FragmentNavigate(direction)
};
}
internal override int GetChildId() => 0;
internal override VARIANT GetPropertyValue(UIA_PROPERTY_ID propertyID)
=> propertyID switch
{
UIA_PROPERTY_ID.UIA_HasKeyboardFocusPropertyId => (VARIANT)(this.TryGetOwnerAs(out TabPage? owningTabPage) && owningTabPage.Focused),
UIA_PROPERTY_ID.UIA_IsKeyboardFocusablePropertyId
// This is necessary for compatibility with MSAA proxy:
// IsKeyboardFocusable = true regardless the control is enabled/disabled.
=> VARIANT.True,
_ => base.GetPropertyValue(propertyID)
};
internal override bool IsPatternSupported(UIA_PATTERN_ID patternId)
=> patternId switch
{
UIA_PATTERN_ID.UIA_ValuePatternId => false,
_ => base.IsPatternSupported(patternId)
};
private TabAccessibleObject? GetNextSibling()
{
if (!this.TryGetOwnerAs(out TabPage? owningTabPage) || OwningTabControl is null || owningTabPage != OwningTabControl.SelectedTab)
{
return null;
}
return OwningTabControl.TabPages.Count > 0 ? OwningTabControl.TabPages[0].TabAccessibilityObject : null;
}
}
}
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