I am using the DataGrid that comes in the WpfToolkit for .NET 3.5. I am displaying DataTable. I want negative amounts to be red. The number of columns is variable so AutoGenerateColumns is True.
Following the advice here http://wpftutorial.net/DataGrid.html I have done the following. However whenever TemplateSelector is called item is a DataRowView and not cell contents. How can I reference the cell contents??
Public Class AmountDataGrid
Inherits Microsoft.Windows.Controls.DataGrid
Public Property CellTemplateSelector() As DataTemplateSelector
Get
Return DirectCast(GetValue(CellTemplateSelectorProperty), DataTemplateSelector)
End Get
Set(value As DataTemplateSelector)
SetValue(CellTemplateSelectorProperty, value)
End Set
End Property
Public Shared ReadOnly CellTemplateSelectorProperty As DependencyProperty = DependencyProperty.Register("Selector", GetType(DataTemplateSelector), GetType(AmountDataGrid), New FrameworkPropertyMetadata(Nothing))
Protected Overrides Sub OnAutoGeneratingColumn(e As Microsoft.Windows.Controls.DataGridAutoGeneratingColumnEventArgs)
e.Cancel = True
Columns.Add(New Microsoft.Windows.Controls.DataGridTemplateColumn() With {.Header = e.Column.Header, .CellTemplateSelector = CellTemplateSelector})
End Sub
End Class
DataGrid in XAML
<l:AmountDataGrid x:Name="dgMonths" Style="{StaticResource MonthsView}" CellTemplateSelector="{StaticResource TemplateSelector}"/>
Selector
Public Class TemplateSelector
Inherits DataTemplateSelector
Private _defaultTemplate As DataTemplate
Public Property DefaultTemplate() As DataTemplate
Get
Return _defaultTemplate
End Get
Set(value As DataTemplate)
_defaultTemplate = value
End Set
End Property
Public Overrides Function SelectTemplate(item As Object, container As System.Windows.DependencyObject) As DataTemplate
Return Me.DefaultTemplate
End Function
End Class
Code that binds the DataTable
strSelect = "TRANSFORM Format(Sum(Items.amount),'#,##0.00') AS total SELECT Accounts.accCategory, Accounts.ID, Accounts.comment AS Account FROM Accounts INNER JOIN Items ON Accounts.ID = Items.accFrom WHERE (((Year([idate]))=2013) AND ((Items.category)<>3 Or (Items.category) Is Null) AND ((Accounts.accCategory)=6 OR (Accounts.accCategory)=7) AND ((Accounts.curr)=1)) GROUP BY Accounts.accCategory, Accounts.ID, Accounts.comment PIVOT Format(idate,'mmm') IN ('Jan','Feb','Mar','Apr', 'May','Jun','Jul','Aug','Sep','Oct','Nov','Dec')"
dsmcmd = New OleDbDataAdapter(strSelect, cn)
dsmcmd.Fill(dsm, "Totals")
dgMonths.ItemsSource = dsm.Tables("Totals").DefaultView
Thanks Andy
Figured it out.... rather complicated for something that should really be simple!
XAML
<Window.Resources>
<l:DGAmountConverter x:Key="DGAmountConverter"/>
<l:DGColourConverter x:Key="DGColourConverter"/>
<DataTemplate x:Key="ColourAmount">
<Grid>
<TextBlock Text="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=dg:DataGridCell}, Converter={StaticResource DGAmountConverter}}" Foreground="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=dg:DataGridCell}, Converter={StaticResource DGColourConverter}}"/>
</Grid>
</DataTemplate>
<l:TemplateSelector x:Key="TemplateSelector" DefaultTemplate="{StaticResource ColourAmount}"/>
</Window.Resources>
....
<l:AmountDataGrid x:Name="dgMonths" Style="{StaticResource MonthsView}" CellTemplateSelector="{StaticResource TemplateSelector}"/>
Code behind
Public Class AmountDataGrid
Inherits Microsoft.Windows.Controls.DataGrid
Public Property CellTemplateSelector() As DataTemplateSelector
Get
Return DirectCast(GetValue(CellTemplateSelectorProperty), DataTemplateSelector)
End Get
Set(value As DataTemplateSelector)
SetValue(CellTemplateSelectorProperty, value)
End Set
End Property
Public Shared ReadOnly CellTemplateSelectorProperty As DependencyProperty = DependencyProperty.Register("Selector", GetType(DataTemplateSelector), GetType(AmountDataGrid), New FrameworkPropertyMetadata(Nothing))
Protected Overrides Sub OnAutoGeneratingColumn(e As Microsoft.Windows.Controls.DataGridAutoGeneratingColumnEventArgs)
e.Cancel = True
Columns.Add(New Microsoft.Windows.Controls.DataGridTemplateColumn() With {.Header = e.Column.Header, .CellTemplateSelector = CellTemplateSelector})
End Sub
End Class
Public Class TemplateSelector
Inherits DataTemplateSelector
Private _defaultTemplate As DataTemplate
Public Property DefaultTemplate() As DataTemplate
Get
Return _defaultTemplate
End Get
Set(value As DataTemplate)
_defaultTemplate = value
End Set
End Property
Public Overrides Function SelectTemplate(item As Object, container As System.Windows.DependencyObject) As DataTemplate
Return Me.DefaultTemplate
End Function
End Class
Class DGAmountConverter
Implements IValueConverter
Public Function Convert(value As Object, targetType As Type, parameter As Object, culture As CultureInfo) As Object Implements IValueConverter.Convert
Dim cell As Microsoft.Windows.Controls.DataGridCell = TryCast(value, Microsoft.Windows.Controls.DataGridCell)
If cell IsNot Nothing Then
Dim colNum As Integer = cell.Column.DisplayIndex
Dim cp As ContentPresenter = TryCast(cell.Content, ContentPresenter)
Dim view As DataRowView = TryCast(cp.Content, DataRowView)
If view IsNot Nothing Then
Return TryCast(view.Row.ItemArray(colNum), Object)
End If
End If
Return DependencyProperty.UnsetValue
End Function
Public Function ConvertBack(value As Object, targetType As Type, parameter As Object, culture As CultureInfo) As Object Implements IValueConverter.ConvertBack
Return Nothing
End Function
End Class
Class DGColourConverter
Implements IValueConverter
Public Function Convert(value As Object, targetType As Type, parameter As Object, culture As CultureInfo) As Object Implements IValueConverter.Convert
Dim cell As Microsoft.Windows.Controls.DataGridCell = TryCast(value, Microsoft.Windows.Controls.DataGridCell)
If cell IsNot Nothing Then
Dim colNum As Integer = cell.Column.DisplayIndex
Dim cp As ContentPresenter = TryCast(cell.Content, ContentPresenter)
Dim view As DataRowView = TryCast(cp.Content, DataRowView)
If view IsNot Nothing Then
Dim obj As Object = view.Row.ItemArray(colNum)
If obj Is Nothing OrElse Val(obj) >= 0 Then
Return New SolidColorBrush(Colors.White)
Else
Return New SolidColorBrush(Colors.Red)
End If
End If
End If
Return DependencyProperty.UnsetValue
End Function
Public Function ConvertBack(value As Object, targetType As Type, parameter As Object, culture As CultureInfo) As Object Implements IValueConverter.ConvertBack
Return Nothing
End Function
End Class