Option Strict On

Imports System.Collections
Imports DevExpress.XtraGrid
Imports DevExpress.XtraGrid.Columns
Imports DevExpress.XtraGrid.Views.Grid

Public Class RefreshHelper
    <Serializable>
    Public Structure RowInfo
        Public Id As Object
        Public level As Integer
    End Structure

    Private ReadOnly view As GridView
    Private ReadOnly keyFieldName As String
    Private _saveExpList As ArrayList
    Private _saveSelList As ArrayList
    Private _saveMasterRowsList As ArrayList
    Private visibleRowIndex As Integer = -1

    Public Sub New(ByVal view As GridView, ByVal keyFieldName As String)
        Me.view = view
        Me.keyFieldName = keyFieldName
    End Sub

    Public ReadOnly Property SaveExpList As ArrayList
        Get
            If _saveExpList Is Nothing Then
                _saveExpList = New ArrayList()
            End If
            Return _saveExpList
        End Get
    End Property

    Public ReadOnly Property SaveSelList As ArrayList
        Get
            If _saveSelList Is Nothing Then
                _saveSelList = New ArrayList()
            End If
            Return _saveSelList
        End Get
    End Property

    Public ReadOnly Property SaveMasterRowsList As ArrayList
        Get
            If _saveMasterRowsList Is Nothing Then
                _saveMasterRowsList = New ArrayList()
            End If
            Return _saveMasterRowsList
        End Get
    End Property

    Protected Function FindParentRowHandle(ByVal rowInfo As RowInfo, ByVal rowHandle As Integer) As Integer
        Dim result As Integer = view.GetParentRowHandle(rowHandle)

        While view.GetRowLevel(result) <> rowInfo.level
            result = view.GetParentRowHandle(result)
        End While

        Return result
    End Function

    Protected Sub ExpandRowByRowInfo(ByVal rowInfo As RowInfo)
        Dim dataRowHandle As Integer = view.LocateByValue(0, view.Columns(keyFieldName), rowInfo.Id)

        If dataRowHandle <> GridControl.InvalidRowHandle Then
            Dim parentRowHandle As Integer = FindParentRowHandle(rowInfo, dataRowHandle)
            view.SetRowExpanded(parentRowHandle, True, False)
        End If
    End Sub

    Protected Function GetRowHandleToSelect(ByVal rowInfo As RowInfo) As Integer
        Dim dataRowHandle As Integer = view.LocateByValue(0, view.Columns(keyFieldName), rowInfo.Id)

        If dataRowHandle <> GridControl.InvalidRowHandle Then
            If view.GetRowLevel(dataRowHandle) <> rowInfo.level Then Return FindParentRowHandle(rowInfo, dataRowHandle)
        End If

        Return dataRowHandle
    End Function

    Protected Sub SelectRowByRowInfo(ByVal rowInfo As RowInfo, ByVal isFocused As Boolean)
        If isFocused Then
            view.FocusedRowHandle = GetRowHandleToSelect(rowInfo)
        Else
            view.SelectRow(GetRowHandleToSelect(rowInfo))
        End If
    End Sub

    Public Sub SaveSelectionViewInfo(ByVal list As ArrayList)
        list.Clear()
        Dim column As GridColumn = view.Columns(keyFieldName)
        Dim rowInfo As RowInfo
        Dim selectionArray As Integer() = view.GetSelectedRows()

        If selectionArray IsNot Nothing Then

            For i As Integer = 0 To selectionArray.Length - 1
                Dim dataRowHandle As Integer = selectionArray(i)
                rowInfo.level = view.GetRowLevel(dataRowHandle)
                If dataRowHandle < 0 Then dataRowHandle = view.GetDataRowHandleByGroupRowHandle(dataRowHandle)
                rowInfo.Id = view.GetRowCellValue(dataRowHandle, column)
                list.Add(rowInfo)
            Next
        End If

        rowInfo.Id = view.GetRowCellValue(view.FocusedRowHandle, column)
        rowInfo.level = view.GetRowLevel(view.FocusedRowHandle)
        list.Add(rowInfo)
    End Sub

    Public Sub SaveExpansionViewInfo(ByVal list As ArrayList)
        If view.GroupedColumns.Count = 0 Then Return
        list.Clear()
        Dim column As GridColumn = view.Columns(keyFieldName)

        For i As Integer = -1 To Integer.MinValue + 1
            If Not view.IsValidRowHandle(i) Then Exit For

            If view.GetRowExpanded(i) Then
                Dim rowInfo As RowInfo
                Dim dataRowHandle As Integer = view.GetDataRowHandleByGroupRowHandle(i)
                rowInfo.Id = view.GetRowCellValue(dataRowHandle, column)
                rowInfo.level = view.GetRowLevel(i)
                list.Add(rowInfo)
            End If
        Next
    End Sub

    Public Sub SaveExpandedMasterRows(ByVal list As ArrayList)
        If view.GridControl.Views.Count = 1 Then Return
        list.Clear()
        Dim column As GridColumn = view.Columns(keyFieldName)

        For i As Integer = 0 To view.DataRowCount - 1
            If view.GetMasterRowExpanded(i) Then list.Add(view.GetRowCellValue(i, column))
        Next
    End Sub

    Public Sub SaveVisibleIndex()
        visibleRowIndex = view.GetVisibleIndex(view.FocusedRowHandle) - view.TopRowIndex
    End Sub

    Public Sub LoadVisibleIndex()
        view.MakeRowVisible(view.FocusedRowHandle, True)
        view.TopRowIndex = view.GetVisibleIndex(view.FocusedRowHandle) - visibleRowIndex
    End Sub

    Public Sub LoadSelectionViewInfo(ByVal list As ArrayList)
        view.BeginSelection()

        Try
            view.ClearSelection()

            For i As Integer = 0 To list.Count - 1
                SelectRowByRowInfo(CType(list(i), RowInfo), i = list.Count - 1)
            Next

        Finally
            view.EndSelection()
        End Try
    End Sub

    Public Sub LoadExpansionViewInfo(ByVal list As ArrayList)
        If view.GroupedColumns.Count = 0 Then Return
        view.BeginUpdate()

        Try
            view.CollapseAllGroups()

            For Each info As RowInfo In list
                ExpandRowByRowInfo(info)
            Next

        Finally
            view.EndUpdate()
        End Try
    End Sub

    Public Sub LoadExpandedMasterRows(ByVal list As ArrayList)
        view.BeginUpdate()

        Try
            view.CollapseAllDetails()
            Dim column As GridColumn = view.Columns(keyFieldName)

            For i As Integer = 0 To list.Count - 1
                Dim rowHandle As Integer = view.LocateByValue(0, column, list(i))
                view.SetMasterRowExpanded(rowHandle, True)
            Next

        Finally
            view.EndUpdate()
        End Try
    End Sub

    Public Sub SaveViewInfo()
        SaveExpandedMasterRows(SaveMasterRowsList)
        SaveExpansionViewInfo(SaveExpList)
        SaveSelectionViewInfo(SaveSelList)
        SaveVisibleIndex()
    End Sub

    Public Sub LoadViewInfo()
        LoadExpandedMasterRows(SaveMasterRowsList)
        LoadExpansionViewInfo(SaveExpList)
        LoadSelectionViewInfo(SaveSelList)
        LoadVisibleIndex()
    End Sub
End Class