WPF Datagrid DataGridTemplateColumn tab focus issue - wpf

Question

I am facing tab issue with WPF DataGrid DataGridTemplateColumn.I need to tab twice to get the focus on to the control with in the DataGridTemplateColumn.I tried below way as specified in this site for this issue. But still my problem is not resolved.
<my:DataGrid AutoGenerateColumns="False" Name="dgCB" Margin="8,32,0,0" SelectionMode="Single" GridLinesVisibility="All" FontSize="13" SelectionUnit="Cell"
KeyboardNavigation.TabNavigation="Continue" CanUserAddRows="False" CanUserDeleteRows="False"
EnableColumnVirtualization="True" VerticalAlignment="Top"
RowDetailsVisibilityMode="VisibleWhenSelected"
IsSynchronizedWithCurrentItem="True"
CanUserSortColumns="False"
CanUserReorderColumns="False"
CanUserResizeColumns="True"
CanUserResizeRows="True"
HorizontalAlignment="Left"
Width="964"
Height="416">
<my:DataGrid.Columns>
<my:DataGridTemplateColumn Header="Tis">
<my:DataGridTemplateColumn.CellStyle>
<Style TargetType="{x:Type DataGridCell}">
<Setter Property="KeyboardNavigation.IsTabStop" Value="False"/>
</Style>
</my:DataGridTemplateColumn.CellStyle>
<my:DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<TextBox Name="txtC" PBOValidation:TextBoxMaskBehavior.Mask="Integer" LostFocus="txtC_LostFocus" Text="{Binding Path=TIME}" GotKeyboardFocus="txtC_GotKeyboardFocus"></TextBox>
</DataTemplate>
</my:DataGridTemplateColumn.CellTemplate>
</my:DataGridTemplateColumn>
</my:DataGrid.Columns>
</my:DataGrid>
In code behind file I am written the event handler like below.
private void txtC_GotKeyboardFocus(object sender, KeyboardFocusChangedEventArgs e)
{
try
{
((TextBox)sender).SelectAll();
}
catch { }
}
private void txtC_LostFocus(object sender, RoutedEventArgs e)
{
if (string.IsNullOrEmpty(((System.Windows.Controls.TextBox)(sender)).Text.Trim()))
{
((System.Windows.Controls.TextBox)(sender)).Text = 0.ToString();
}
}
But still my problem is not resolved and I am getting below error:
'DataGridCell' targettype does not match type of element 'DataGridCell'
Please help me to resolve my tab focus issue.

Answer 1

You should define a behavior on DataGrid which focus on the clicked cell on first click itself. The below behavior does the required:
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
/// <summary>
/// Defines a dependency property to allow the dataGridCell to become editable in mouse single click .
/// </summary>
public class DataGridCellSingleClickEditDependency : DependencyObject
{
/// <summary>
/// The is allow single click edit property
/// </summary>
public static readonly DependencyProperty IsAllowSingleClickEditProperty = DependencyProperty.RegisterAttached("IsAllowSingleClickEdit", typeof(bool), typeof(DataGridCellSingleClickEditDependency), new PropertyMetadata(false, IsAllowSingleClickEditChanged));
/// <summary>
/// Gets or sets a value indicating whether this instance is allow single click edit.
/// </summary>
/// <value>
/// <c>true</c> if this instance is allow single click edit; otherwise, <c>false</c>.
/// </value>
public bool IsAllowSingleClickEdit
{
get
{
return (bool)this.GetValue(IsAllowSingleClickEditProperty);
}
set
{
this.SetValue(IsAllowSingleClickEditProperty, value);
}
}
/// <summary>
/// Determines whether [is allow single click edit changed] [the specified sender].
/// </summary>
/// <param name="sender">The sender.</param>
/// <param name="e">The <see cref="DependencyPropertyChangedEventArgs"/> instance containing the event data.</param>
private static void IsAllowSingleClickEditChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
{
DataGridCell dataGridCell = sender as DataGridCell;
if (dataGridCell != null)
{
if (e.NewValue.Equals(true))
{
dataGridCell.GotFocus += DataGridCellGotFocusHandler;
}
else
{
dataGridCell.GotFocus -= DataGridCellGotFocusHandler;
}
}
}
/// <summary>
/// Finds the visual parent.
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="element">The element.</param>
/// <returns></returns>
private static T FindVisualParent<T>(UIElement element) where T : UIElement
{
UIElement parent = element;
while (parent != null)
{
T correctlyTyped = parent as T;
if (correctlyTyped != null)
{
return correctlyTyped;
}
parent = VisualTreeHelper.GetParent(parent) as UIElement;
}
return null;
}
/// <summary>
/// Handles the GotFocus event of the AssociatedObject control.
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">The <see cref="RoutedEventArgs"/> instance containing the event data.</param>
private static void DataGridCellGotFocusHandler(object sender, RoutedEventArgs e)
{
DataGridCell cell = sender as DataGridCell;
if (cell != null && !cell.IsEditing && !cell.IsReadOnly)
{
if (!cell.IsFocused)
{
cell.Focus();
}
DataGrid dataGrid = FindVisualParent<DataGrid>(cell);
if (dataGrid != null)
{
dataGrid.BeginEdit(e);
if (dataGrid.SelectionUnit != DataGridSelectionUnit.FullRow)
{
if (!cell.IsSelected)
{
cell.IsSelected = true;
}
}
else
{
DataGridRow row = FindVisualParent<DataGridRow>(cell);
if (row != null && !row.IsSelected)
{
row.IsSelected = true;
}
}
}
}
}
}
Now to attached over DataGrid, you can define a Keyed style for DataGridCell
<Style x:Key="DataGridCellSingleClickEditStyle" TargetType="{x:Type DataGridCell}">
<Setter Property="localBehaviors:DataGridCellSingleClickEditDependency.IsAllowSingleClickEdit" Value="True" />
</Style>
Not to apply over DataGrid set the CellStyle
<DataGrid CellStyle ="{StaticResource DataGridCellSingleClickEditStyle}">
.......
</DataGrid>