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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 Windows.Win32.System.Variant;
using Windows.Win32.UI.Accessibility;
namespace System.Windows.Forms;
public partial class ProgressBar
{
internal class ProgressBarAccessibleObject : ControlAccessibleObject
{
internal ProgressBarAccessibleObject(ProgressBar owner) : base(owner)
{
}
internal override bool IsIAccessibleExSupported() => true;
internal override bool IsPatternSupported(UIA_PATTERN_ID patternId) => patternId switch
{
UIA_PATTERN_ID.UIA_ValuePatternId or UIA_PATTERN_ID.UIA_RangeValuePatternId => true,
_ => base.IsPatternSupported(patternId),
};
internal override VARIANT GetPropertyValue(UIA_PROPERTY_ID propertyID) =>
propertyID switch
{
UIA_PROPERTY_ID.UIA_ControlTypePropertyId when this.GetOwnerAccessibleRole() == AccessibleRole.Default
// If we don't set a default role for the accessible object
// it will be retrieved from Windows.
// And we don't have a 100% guarantee it will be correct, hence set it ourselves.
=> (VARIANT)(int)UIA_CONTROLTYPE_ID.UIA_ProgressBarControlTypeId,
UIA_PROPERTY_ID.UIA_IsKeyboardFocusablePropertyId =>
// This is necessary for compatibility with MSAA proxy:
// IsKeyboardFocusable = true regardless the control is enabled/disabled.
VARIANT.True,
UIA_PROPERTY_ID.UIA_IsRangeValuePatternAvailablePropertyId => VARIANT.True,
UIA_PROPERTY_ID.UIA_IsValuePatternAvailablePropertyId => VARIANT.True,
UIA_PROPERTY_ID.UIA_RangeValueIsReadOnlyPropertyId => VARIANT.True,
UIA_PROPERTY_ID.UIA_RangeValueLargeChangePropertyId => (VARIANT)double.NaN,
UIA_PROPERTY_ID.UIA_RangeValueSmallChangePropertyId => (VARIANT)double.NaN,
_ => base.GetPropertyValue(propertyID)
};
internal override void SetValue(double newValue)
=> throw new InvalidOperationException("Progress Bar is read-only.");
internal override double LargeChange => double.NaN;
internal override double Maximum => this.TryGetOwnerAs(out ProgressBar? owner) ? owner.Maximum : 0;
internal override double Minimum => this.TryGetOwnerAs(out ProgressBar? owner) ? owner.Minimum : 0;
internal override double SmallChange => double.NaN;
internal override double RangeValue => this.TryGetOwnerAs(out ProgressBar? owner) ? owner.Value : 0;
internal override bool IsReadOnly => true;
}
}
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