Imports DevExpress.Data
Imports DevExpress.XtraGrid.Controls
Imports DevExpress.XtraGrid.Views.Base
Imports DevExpress.XtraGrid.Views.Grid

Public Class frmLookupGrid
    Public Property MultiSelect As Boolean
    Public Property DataSource As DataTable
    Public Property SelectedValues As List(Of Object)

    Private originalValues As List(Of Object)

    Private Sub frmLookupGrid_Load(sender As Object, e As EventArgs) Handles Me.Load
        Dim view As GridView = gridLookup.DefaultView

        ' Anzeige Eigeschaften setzen
        view.OptionsFind.AlwaysVisible = True

        If MultiSelect Then
            Text = "Wählen Sie einen oder mehrere Werte:"
            view.OptionsSelection.MultiSelect = True
            view.OptionsSelection.MultiSelectMode = GridMultiSelectMode.CheckBoxRowSelect
        Else
            Text = "Wählen Sie einen Wert:"
            view.OptionsSelection.MultiSelect = False
            view.OptionsSelection.MultiSelectMode = GridMultiSelectMode.RowSelect
        End If

        ' Datasource setzen
        gridLookup.DataSource = DataSource

        ' Wenn Selected Values nicht gesetzt ist, leere Liste anlegen
        If SelectedValues Is Nothing Then
            SelectedValues = New List(Of Object)
        End If

        ' Ursprüngliche Werte zwischenspeichern
        originalValues = SelectedValues

        SyncItemsWithView(view)

        ' Focus auf Find panel setzen
        view.ShowFindPanel()
    End Sub

    Private Sub frmLookupGrid_Shown(sender As Object, e As EventArgs) Handles Me.Shown
        Dim findEditor As DevExpress.XtraEditors.MRUEdit = gridLookup.Controls.Find("teFind", True).FirstOrDefault()
        If findEditor IsNot Nothing Then
            'AddHandler findEditor.KeyUp, AddressOf FindPanel_KeyUp
            AddHandler findEditor.EditValueChanged, AddressOf FindPanel_KeyUp
        End If
    End Sub



    Private OldFindPanelValue As String = ""

    Private Sub FindPanel_KeyUp(sender As Object, e As EventArgs)
        Dim findEditor As DevExpress.XtraEditors.MRUEdit = sender

        If findEditor.EditValue.ToString.Count = 0 And OldFindPanelValue.Count > 0 Then
            SyncItemsWithView(viewLookup)
        End If

        OldFindPanelValue = findEditor.EditValue
    End Sub

    Private Sub SyncItemsWithView(view As GridView)
        ' Wenn Vorbelegungen existieren 
        ' und Mehrfachauswahl ausgewählt ist, werden diese angehakt
        If SelectedValues.Count > 0 And MultiSelect Then
            For i = 0 To view.DataRowCount - 1
                Dim rowHandle = view.GetRowHandle(i)
                Dim rowView As DataRowView = view.GetRow(rowHandle)

                If rowView IsNot Nothing Then
                    Dim row As DataRow = rowView.Row
                    Dim value = row.Item(0)

                    If SelectedValues.Contains(value) Then
                        view.SelectRow(rowHandle)
                    End If
                End If
            Next
        End If
    End Sub

    Private Sub btnOK_Click(sender As Object, e As EventArgs) Handles btnOK.Click
        Dim view As GridView = gridLookup.DefaultView
        Dim selectedRows = view.GetSelectedRows()

        Dim values As New List(Of Object)

        For Each rowHandle In selectedRows
            Dim value = view.GetDataRow(rowHandle)
            values.Add(value.Item(0))
        Next

        If MultiSelect Then
            SelectedValues = values
        Else
            SelectedValues = New List(Of Object) From {values.First()}
        End If
    End Sub

    Private Sub btnClear_Click(sender As Object, e As EventArgs) Handles btnClear.Click
        SelectedValues = New List(Of Object)
    End Sub

    Private Sub frmLookupGrid_KeyDown(sender As Object, e As KeyEventArgs) Handles Me.KeyDown
        If e.KeyCode = Keys.Escape Then
            Close()
        End If
    End Sub

    Private Sub viewLookup_SelectionChanged(sender As Object, e As DevExpress.Data.SelectionChangedEventArgs) Handles viewLookup.SelectionChanged
        If e.Action = System.ComponentModel.CollectionChangeAction.Add Then
            Dim row = viewLookup.GetRow(e.ControllerRow)
            Dim value As Object = row.item(0)

            SelectedValues.Add(value)
        ElseIf e.Action = System.ComponentModel.CollectionChangeAction.Remove Then
            Dim row = viewLookup.GetRow(e.ControllerRow)
            Dim value As Object = row.item(0)

            SelectedValues = (From v In SelectedValues
                              Where v <> value
                              Select v).ToList()
        End If
    End Sub


End Class