File: System\Windows\Forms\AccessibleObjects\VScrollBar.ScrollBarFirstPageButtonAccessibleObjectTests.cs
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Project: src\src\System.Windows.Forms\tests\UnitTests\System.Windows.Forms.Tests.csproj (System.Windows.Forms.Tests)
// 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 System.Windows.Forms.TestUtilities;
using Windows.Win32.UI.Accessibility;
using static System.Windows.Forms.ScrollBar;
 
namespace System.Windows.Forms.Tests.AccessibleObjects;
 
public class VScrollBar_ScrollBarFirstPageButtonAccessibleObjectTests
{
    [WinFormsTheory]
    [CommonMemberData(typeof(ScrollBarTestHelper), nameof(ScrollBarTestHelper.ScrollBarAccessibleObject_TestData))]
    public void VScrollBarFirstPageButtonAccessibleObject_GetChild_ReturnNull(bool createControl, RightToLeft rightToLeft, int minimum, int maximum, int value)
    {
        using VScrollBar scrollBar = GetVScrollBar(createControl, rightToLeft, minimum, maximum, value);
        ScrollBarFirstPageButtonAccessibleObject accessibleObject = GetFirstPageButton(scrollBar);
 
        Assert.Null(accessibleObject.GetChild(-1));
        Assert.Null(accessibleObject.GetChild(0));
        Assert.Null(accessibleObject.GetChild(1));
        Assert.Equal(createControl, scrollBar.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [CommonMemberData(typeof(ScrollBarTestHelper), nameof(ScrollBarTestHelper.ScrollBarAccessibleObject_TestData))]
    public void VScrollBarFirstPageButtonAccessibleObject_GetChildCount_ReturnMinusOne(bool createControl, RightToLeft rightToLeft, int minimum, int maximum, int value)
    {
        using VScrollBar scrollBar = GetVScrollBar(createControl, rightToLeft, minimum, maximum, value);
        ScrollBarFirstPageButtonAccessibleObject accessibleObject = GetFirstPageButton(scrollBar);
 
        Assert.Equal(-1, accessibleObject.GetChildCount());
        Assert.Equal(createControl, scrollBar.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [CommonMemberData(typeof(ScrollBarTestHelper), nameof(ScrollBarTestHelper.ScrollBarAccessibleObject_WithoutCreateControl_TestData))]
    public void VScrollBarFirstPageButtonAccessibleObject_Bounds_ReturnEmptyRectangle_HandleIsNotCreated(RightToLeft rightToLeft, int minimum, int maximum, int value)
    {
        using VScrollBar scrollBar = GetVScrollBar(createControl: false, rightToLeft, minimum, maximum, value);
        ScrollBarFirstPageButtonAccessibleObject accessibleObject = GetFirstPageButton(scrollBar);
 
        Assert.Equal(Rectangle.Empty, accessibleObject.Bounds);
        Assert.False(scrollBar.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [CommonMemberData(typeof(ScrollBarTestHelper), nameof(ScrollBarTestHelper.VScrollBarAccessibleObject_FirstPageButtonIsHidden_TestData))]
    public void VScrollBarFirstPageButtonAccessibleObject_Bounds_ReturnEmptyRectangle_FirstPageButtonIsHidden(RightToLeft rightToLeft, int minimum, int maximum, int value)
    {
        using VScrollBar scrollBar = GetVScrollBar(createControl: false, rightToLeft, minimum, maximum, value);
        ScrollBarFirstPageButtonAccessibleObject accessibleObject = GetFirstPageButton(scrollBar);
 
        Assert.Equal(Rectangle.Empty, accessibleObject.Bounds);
        Assert.False(scrollBar.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [CommonMemberData(typeof(ScrollBarTestHelper), nameof(ScrollBarTestHelper.ScrollBarAccessibleObject_WithoutCreateControl_TestData))]
    public void VScrollBarFirstPageButtonAccessibleObject_DefaultAction_ReturnNotNull_HandleIsCreated(RightToLeft rightToLeft, int minimum, int maximum, int value)
    {
        using VScrollBar scrollBar = GetVScrollBar(createControl: true, rightToLeft, minimum, maximum, value);
        ScrollBarFirstPageButtonAccessibleObject accessibleObject = GetFirstPageButton(scrollBar);
 
        Assert.NotEmpty(accessibleObject.DefaultAction);
        Assert.True(scrollBar.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [CommonMemberData(typeof(ScrollBarTestHelper), nameof(ScrollBarTestHelper.ScrollBarAccessibleObject_WithoutCreateControl_TestData))]
    public void VScrollBarFirstPageButtonAccessibleObject_DefaultAction_ReturnNull_HandleIsNotCreated(RightToLeft rightToLeft, int minimum, int maximum, int value)
    {
        using VScrollBar scrollBar = GetVScrollBar(createControl: false, rightToLeft, minimum, maximum, value);
        ScrollBarFirstPageButtonAccessibleObject accessibleObject = GetFirstPageButton(scrollBar);
 
        Assert.Null(accessibleObject.DefaultAction);
        Assert.False(scrollBar.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [CommonMemberData(typeof(ScrollBarTestHelper), nameof(ScrollBarTestHelper.ScrollBarAccessibleObject_WithoutCreateControl_TestData))]
    public void VScrollBarFirstPageButtonAccessibleObject_Description_ReturnNotNull_HandleIsCreated(RightToLeft rightToLeft, int minimum, int maximum, int value)
    {
        using VScrollBar scrollBar = GetVScrollBar(createControl: true, rightToLeft, minimum, maximum, value);
        ScrollBarFirstPageButtonAccessibleObject accessibleObject = GetFirstPageButton(scrollBar);
 
        Assert.NotEmpty(accessibleObject.Description);
        Assert.True(scrollBar.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [CommonMemberData(typeof(ScrollBarTestHelper), nameof(ScrollBarTestHelper.ScrollBarAccessibleObject_WithoutCreateControl_TestData))]
    public void VScrollBarFirstPageButtonAccessibleObject_Description_ReturnNull_HandleIsNotCreated(RightToLeft rightToLeft, int minimum, int maximum, int value)
    {
        using VScrollBar scrollBar = GetVScrollBar(createControl: false, rightToLeft, minimum, maximum, value);
        ScrollBarFirstPageButtonAccessibleObject accessibleObject = GetFirstPageButton(scrollBar);
 
        Assert.Null(accessibleObject.Description);
        Assert.False(scrollBar.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [CommonMemberData(typeof(ScrollBarTestHelper), nameof(ScrollBarTestHelper.ScrollBarAccessibleObject_WithoutCreateControl_TestData))]
    public void VScrollBarFirstPageButtonAccessibleObject_Name_ReturnNotNull_HandleIsCreated(RightToLeft rightToLeft, int minimum, int maximum, int value)
    {
        using VScrollBar scrollBar = GetVScrollBar(createControl: true, rightToLeft, minimum, maximum, value);
        ScrollBarFirstPageButtonAccessibleObject accessibleObject = GetFirstPageButton(scrollBar);
 
        Assert.NotEmpty(accessibleObject.Name);
        Assert.True(scrollBar.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [CommonMemberData(typeof(ScrollBarTestHelper), nameof(ScrollBarTestHelper.ScrollBarAccessibleObject_WithoutCreateControl_TestData))]
    public void VScrollBarFirstPageButtonAccessibleObject_Name_ReturnNull_HandleIsNotCreated(RightToLeft rightToLeft, int minimum, int maximum, int value)
    {
        using VScrollBar scrollBar = GetVScrollBar(createControl: false, rightToLeft, minimum, maximum, value);
        ScrollBarFirstPageButtonAccessibleObject accessibleObject = GetFirstPageButton(scrollBar);
 
        Assert.Null(accessibleObject.Name);
        Assert.False(scrollBar.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [CommonMemberData(typeof(ScrollBarTestHelper), nameof(ScrollBarTestHelper.ScrollBarAccessibleObject_TestData))]
    public void VScrollBarFirstPageButtonAccessibleObject_Role_ReturnNotNull(bool createControl, RightToLeft rightToLeft, int minimum, int maximum, int value)
    {
        using VScrollBar scrollBar = GetVScrollBar(createControl, rightToLeft, minimum, maximum, value);
        ScrollBarFirstPageButtonAccessibleObject accessibleObject = GetFirstPageButton(scrollBar);
        AccessibleRole expectedRole = createControl ? AccessibleRole.PushButton : AccessibleRole.None;
 
        Assert.Equal(expectedRole, accessibleObject.Role);
        Assert.Equal(createControl, scrollBar.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [CommonMemberData(typeof(ScrollBarTestHelper), nameof(ScrollBarTestHelper.ScrollBarAccessibleObject_WithoutCreateControl_TestData))]
    public void VScrollBarFirstPageButtonAccessibleObject_State_ReturnNone_IfHandleIsNotCreated(RightToLeft rightToLeft, int minimum, int maximum, int value)
    {
        using VScrollBar scrollBar = GetVScrollBar(createControl: false, rightToLeft, minimum, maximum, value);
        ScrollBarFirstPageButtonAccessibleObject accessibleObject = GetFirstPageButton(scrollBar);
 
        Assert.Equal(AccessibleStates.None, accessibleObject.State);
        Assert.False(scrollBar.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [CommonMemberData(typeof(ScrollBarTestHelper), nameof(ScrollBarTestHelper.ScrollBarAccessibleObject_TestData))]
    public void VScrollBarFirstPageButtonAccessibleObject_InvokePattern_Supported(bool createControl, RightToLeft rightToLeft, int minimum, int maximum, int value)
    {
        using VScrollBar scrollBar = GetVScrollBar(createControl, rightToLeft, minimum, maximum, value);
        ScrollBarFirstPageButtonAccessibleObject accessibleObject = GetFirstPageButton(scrollBar);
 
        Assert.Equal(createControl, accessibleObject.IsPatternSupported(UIA_PATTERN_ID.UIA_InvokePatternId));
        Assert.Equal(createControl, scrollBar.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [CommonMemberData(typeof(ScrollBarTestHelper), nameof(ScrollBarTestHelper.VScrollBarAccessibleObject_FirstPageButtonIsDisplayed_TestData))]
    public void VScrollBarFirstPageButtonAccessibleObject_FragmentNavigate_ReturnsExpected_ButtonIsDisplayed(RightToLeft rightToLeft, int minimum, int maximum, int value)
    {
        using VScrollBar scrollBar = GetVScrollBar(createControl: true, rightToLeft, minimum, maximum, value);
        var scrollBarAccessibleObject = (ScrollBar.ScrollBarAccessibleObject)scrollBar.AccessibilityObject;
        ScrollBarFirstPageButtonAccessibleObject accessibleObject = GetFirstPageButton(scrollBar);
 
        AccessibleObject thumb = scrollBarAccessibleObject.ThumbAccessibleObject;
        AccessibleObject lineButton = scrollBarAccessibleObject.FirstLineButtonAccessibleObject;
        Assert.Equal(scrollBarAccessibleObject, accessibleObject.FragmentNavigate(NavigateDirection.NavigateDirection_Parent));
        Assert.Equal(thumb, accessibleObject.FragmentNavigate(NavigateDirection.NavigateDirection_NextSibling));
        Assert.Equal(lineButton, accessibleObject.FragmentNavigate(NavigateDirection.NavigateDirection_PreviousSibling));
        Assert.Null(accessibleObject.FragmentNavigate(NavigateDirection.NavigateDirection_FirstChild));
        Assert.Null(accessibleObject.FragmentNavigate(NavigateDirection.NavigateDirection_LastChild));
        Assert.True(scrollBar.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [CommonMemberData(typeof(ScrollBarTestHelper), nameof(ScrollBarTestHelper.VScrollBarAccessibleObject_FirstPageButtonIsHidden_TestData))]
    public void VScrollBarFirstPageButtonAccessibleObject_FragmentNavigate_ReturnsNull_ButtonIsHidden(RightToLeft rightToLeft, int minimum, int maximum, int value)
    {
        using VScrollBar scrollBar = GetVScrollBar(createControl: true, rightToLeft, minimum, maximum, value);
        var scrollBarAccessibleObject = (ScrollBar.ScrollBarAccessibleObject)scrollBar.AccessibilityObject;
        ScrollBarFirstPageButtonAccessibleObject accessibleObject = GetFirstPageButton(scrollBar);
 
        Assert.Equal(scrollBarAccessibleObject, accessibleObject.FragmentNavigate(NavigateDirection.NavigateDirection_Parent));
        Assert.Null(accessibleObject.FragmentNavigate(NavigateDirection.NavigateDirection_NextSibling));
        Assert.Null(accessibleObject.FragmentNavigate(NavigateDirection.NavigateDirection_PreviousSibling));
        Assert.Null(accessibleObject.FragmentNavigate(NavigateDirection.NavigateDirection_FirstChild));
        Assert.Null(accessibleObject.FragmentNavigate(NavigateDirection.NavigateDirection_LastChild));
        Assert.True(scrollBar.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [CommonMemberData(typeof(ScrollBarTestHelper), nameof(ScrollBarTestHelper.ScrollBarAccessibleObject_MinimumEqualsMaximum_TestData))]
    public void VScrollBarFirstPageButtonAccessibleObject_FragmentNavigate_ReturnsNull_MinimumEqualsMaximum(RightToLeft rightToLeft, int minimum, int maximum, int value)
    {
        using VScrollBar scrollBar = GetVScrollBar(createControl: true, rightToLeft, minimum, maximum, value);
        var scrollBarAccessibleObject = (ScrollBar.ScrollBarAccessibleObject)scrollBar.AccessibilityObject;
        ScrollBarFirstPageButtonAccessibleObject accessibleObject = GetFirstPageButton(scrollBar);
 
        Assert.Equal(scrollBarAccessibleObject, accessibleObject.FragmentNavigate(NavigateDirection.NavigateDirection_Parent));
        Assert.Null(accessibleObject.FragmentNavigate(NavigateDirection.NavigateDirection_NextSibling));
        Assert.Null(accessibleObject.FragmentNavigate(NavigateDirection.NavigateDirection_PreviousSibling));
        Assert.Null(accessibleObject.FragmentNavigate(NavigateDirection.NavigateDirection_FirstChild));
        Assert.Null(accessibleObject.FragmentNavigate(NavigateDirection.NavigateDirection_LastChild));
        Assert.True(scrollBar.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [CommonMemberData(typeof(ScrollBarTestHelper), nameof(ScrollBarTestHelper.ScrollBarAccessibleObject_WithoutCreateControl_TestData))]
    public void VScrollBarFirstPageButtonAccessibleObject_FragmentNavigate_ReturnsNull_HandleIsNotCreated(RightToLeft rightToLeft, int minimum, int maximum, int value)
    {
        using VScrollBar scrollBar = GetVScrollBar(createControl: false, rightToLeft, minimum, maximum, value);
        ScrollBarFirstPageButtonAccessibleObject accessibleObject = GetFirstPageButton(scrollBar);
 
        Assert.Null(accessibleObject.FragmentNavigate(NavigateDirection.NavigateDirection_Parent));
        Assert.Null(accessibleObject.FragmentNavigate(NavigateDirection.NavigateDirection_NextSibling));
        Assert.Null(accessibleObject.FragmentNavigate(NavigateDirection.NavigateDirection_PreviousSibling));
        Assert.Null(accessibleObject.FragmentNavigate(NavigateDirection.NavigateDirection_FirstChild));
        Assert.Null(accessibleObject.FragmentNavigate(NavigateDirection.NavigateDirection_LastChild));
        Assert.False(scrollBar.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [InlineData(RightToLeft.Yes)]
    [InlineData(RightToLeft.No)]
    public void VScrollBarFirstPageButtonAccessibleObject_Invoke_DecreaseValue(RightToLeft rightToLeft)
    {
        using VScrollBar scrollBar = GetVScrollBar(createControl: true, rightToLeft, minimum: 0, maximum: 100, value: 50);
        ScrollBarFirstPageButtonAccessibleObject accessibleObject = GetFirstPageButton(scrollBar);
 
        Assert.Equal(50, scrollBar.Value);
 
        accessibleObject.Invoke();
 
        Assert.Equal(48, scrollBar.Value);
 
        accessibleObject.Invoke();
 
        Assert.Equal(46, scrollBar.Value);
        Assert.True(scrollBar.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [InlineData(RightToLeft.No, 0, 100)]
    [InlineData(RightToLeft.No, 0, 0)]
    [InlineData(RightToLeft.Yes, 0, 100)]
    [InlineData(RightToLeft.Yes, 0, 0)]
    public void VScrollBarFirstPageButtonAccessibleObject_Invoke_DoesNotWork_OutOfRange(RightToLeft rightToLeft, int value, int maximum)
    {
        using VScrollBar scrollBar = GetVScrollBar(createControl: true, rightToLeft, minimum: 0, maximum, value);
        ScrollBarFirstPageButtonAccessibleObject accessibleObject = GetFirstPageButton(scrollBar);
 
        Assert.Equal(value, scrollBar.Value);
 
        accessibleObject.Invoke();
 
        Assert.Equal(value, scrollBar.Value);
        Assert.True(scrollBar.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [CommonMemberData(typeof(ScrollBarTestHelper), nameof(ScrollBarTestHelper.ScrollBarAccessibleObject_WithoutCreateControl_TestData))]
    public void VScrollBarFirstPageButtonAccessibleObject_Invoke_DoesNotWork_IfHandleIsNotCreated(RightToLeft rightToLeft, int minimum, int maximum, int value)
    {
        using VScrollBar scrollBar = GetVScrollBar(createControl: false, rightToLeft, minimum, maximum, value);
        ScrollBarFirstPageButtonAccessibleObject accessibleObject = GetFirstPageButton(scrollBar);
 
        Assert.Equal(value, scrollBar.Value);
 
        accessibleObject.Invoke();
 
        Assert.Equal(value, scrollBar.Value);
        Assert.False(scrollBar.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [CommonMemberData(typeof(ScrollBarTestHelper), nameof(ScrollBarTestHelper.ScrollBarAccessibleObject_MinimumEqualsMaximum_TestData))]
    public void VScrollBarFirstPageButtonAccessibleObject_Invoke_DoesNotWork_MinimumEqualsMaximum(RightToLeft rightToLeft, int minimum, int maximum, int value)
    {
        using VScrollBar scrollBar = GetVScrollBar(createControl: true, rightToLeft, minimum, maximum, value);
        ScrollBarFirstPageButtonAccessibleObject accessibleObject = GetFirstPageButton(scrollBar);
 
        Assert.Equal(value, scrollBar.Value);
 
        accessibleObject.Invoke();
 
        Assert.Equal(value, scrollBar.Value);
        Assert.True(scrollBar.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [CommonMemberData(typeof(ScrollBarTestHelper), nameof(ScrollBarTestHelper.VScrollBarAccessibleObject_FirstPageButtonIsHidden_TestData))]
    public void VScrollBarFirstPageButtonAccessibleObject_Invoke_DoesNotWork_FirstPageButtonIsHidden(RightToLeft rightToLeft, int minimum, int maximum, int value)
    {
        using VScrollBar scrollBar = GetVScrollBar(createControl: true, rightToLeft, minimum, maximum, value);
        ScrollBarFirstPageButtonAccessibleObject accessibleObject = GetFirstPageButton(scrollBar);
 
        Assert.Equal(value, scrollBar.Value);
 
        accessibleObject.Invoke();
 
        Assert.Equal(value, scrollBar.Value);
        Assert.True(scrollBar.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [CommonMemberData(typeof(ScrollBarTestHelper), nameof(ScrollBarTestHelper.ScrollBarAccessibleObject_TestData))]
    public void VScrollBarFirstPageButtonAccessibleObject_GetPropertyValue_IsEnabledProperty_ReturnsTrue_OwnerEnabled(bool createControl, RightToLeft rightToLeft, int minimum, int maximum, int value)
    {
        using VScrollBar scrollBar = GetVScrollBar(createControl, rightToLeft, minimum, maximum, value);
        scrollBar.Enabled = true;
        ScrollBarFirstPageButtonAccessibleObject accessibleObject = GetFirstPageButton(scrollBar);
 
        Assert.True((bool)accessibleObject.GetPropertyValue(UIA_PROPERTY_ID.UIA_IsEnabledPropertyId));
        Assert.Equal(createControl, scrollBar.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [CommonMemberData(typeof(ScrollBarTestHelper), nameof(ScrollBarTestHelper.ScrollBarAccessibleObject_TestData))]
    public void VScrollBarFirstPageButtonAccessibleObject_GetPropertyValue_IsEnabledProperty_ReturnsFalse_OwnerDisabled(bool createControl, RightToLeft rightToLeft, int minimum, int maximum, int value)
    {
        using VScrollBar scrollBar = GetVScrollBar(createControl, rightToLeft, minimum, maximum, value);
        scrollBar.Enabled = false;
        ScrollBarFirstPageButtonAccessibleObject accessibleObject = GetFirstPageButton(scrollBar);
 
        Assert.False((bool)accessibleObject.GetPropertyValue(UIA_PROPERTY_ID.UIA_IsEnabledPropertyId));
        Assert.Equal(createControl, scrollBar.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [CommonMemberData(typeof(ScrollBarTestHelper), nameof(ScrollBarTestHelper.VScrollBarAccessibleObject_FirstPageButtonIsDisplayed_TestData))]
    public void VScrollBarFirstLineButtonAccessibleObject_IsDisplayed_ReturnsTrue_OwnerVisible(RightToLeft rightToLeft, int minimum, int maximum, int value)
    {
        using VScrollBar scrollBar = GetVScrollBar(createControl: false, rightToLeft, minimum, maximum, value);
        scrollBar.Visible = true;
        ScrollBarFirstPageButtonAccessibleObject accessibleObject = GetFirstPageButton(scrollBar);
 
        Assert.True(accessibleObject.IsDisplayed);
        Assert.False(scrollBar.IsHandleCreated);
    }
 
    [WinFormsTheory]
    [CommonMemberData(typeof(ScrollBarTestHelper), nameof(ScrollBarTestHelper.VScrollBarAccessibleObject_FirstPageButtonIsDisplayed_TestData))]
    public void VScrollBarFirstLineButtonAccessibleObject_IsDisplayed_ReturnsFalse_OwnerInvisible(RightToLeft rightToLeft, int minimum, int maximum, int value)
    {
        using VScrollBar scrollBar = GetVScrollBar(createControl: false, rightToLeft, minimum, maximum, value);
        scrollBar.Visible = false;
        ScrollBarFirstPageButtonAccessibleObject accessibleObject = GetFirstPageButton(scrollBar);
 
        Assert.False(accessibleObject.IsDisplayed);
        Assert.False(scrollBar.IsHandleCreated);
    }
 
    private VScrollBar GetVScrollBar(bool createControl, RightToLeft rightToLeft, int minimum, int maximum, int value)
    {
        VScrollBar vScrollBar = new()
        {
            RightToLeft = rightToLeft,
            Value = value,
            Minimum = minimum,
            Maximum = maximum,
            Size = new Size(200, 50),
            LargeChange = 2,
            SmallChange = 1
        };
 
        if (createControl)
        {
            vScrollBar.CreateControl();
        }
 
        return vScrollBar;
    }
 
    private ScrollBarFirstPageButtonAccessibleObject GetFirstPageButton(ScrollBar scrollBar)
    {
        var accessibleObject = (ScrollBar.ScrollBarAccessibleObject)scrollBar.AccessibilityObject;
        return accessibleObject.FirstPageButtonAccessibleObject;
    }
}