How to support for Enter key to make focus moving in a text column of the listview
I created the following view
<ListView.View>
<GridView>
<GridViewColumn Header="Tester"
DisplayMemberBinding="{Binding User}" />
<GridViewColumn Header="Executed On"
DisplayMemberBinding="{Binding ExecutionDate}" />
<GridViewColumn Header="Comment">
<GridViewColumn.CellTemplate>
<DataTemplate>
<DockPanel>
<TextBox Text="{Binding Comment}" Name="TxtComment"
MinWidth="100" VerticalContentAlign开发者_StackOverflow社区ment="Top"
BorderThickness="0" PreviewKeyDown="TxtComment_PreviewKeyDown"/>
</DockPanel>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
</GridView>
</ListView.View>
Now what I suppose is that, After I entered something in "Comment" field and press the Key "Enter", the next row of the "Comment" field will get focus.
I added the following code of the event "PreviewKeyDown", but it seems that the next whole row will get focus not only the "Comment" field...
Private Sub TxtComment_PreviewKeyDown(ByVal sender As System.Object, ByVal e As System.Windows.Input.KeyEventArgs)
Dim focusRequest As TraversalRequest
Dim focusedElement As Object = sender
Select Case e.Key
Case Key.Enter
focusRequest = New TraversalRequest(FocusNavigationDirection.Down)
Case Else
' Do nothing
Return
End Select
' Do not further propagate event
e.Handled = True
'Move focus
DirectCast(focusedElement, UIElement).MoveFocus(focusRequest)
End Sub
Hope someone can tell me how to solve this problem, ^0^
Add a SelectionChanged event to your ListView to link with your Enter keyboard event, and use VisualTreeHelper to find the textBox.
Here is the ListView XAML; same as your code except I used an ObservableCollection to load data in the ListView (not shown) and I added the SelectionChanged event:
<ListView x:Name="myView" ItemsSource="{Binding Path=MyData}"
SelectionChanged="myView_SelectionChanged">
<ListView.View>
<GridView>
<GridViewColumn Header="Tester"
DisplayMemberBinding="{Binding User}" />
<GridViewColumn Header="Executed On"
DisplayMemberBinding="{Binding ExecutionDate}" />
<GridViewColumn Header="Comment">
<GridViewColumn.CellTemplate>
<DataTemplate>
<DockPanel>
<TextBox Text="{Binding Comment}" Name="TxtComment"
MinWidth="100" VerticalContentAlignment="Top"
BorderThickness="0"
PreviewKeyDown="TxtComment_PreviewKeyDown"/>
</DockPanel>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
</GridView>
</ListView.View>
</ListView>
Here are the event handlers and a helper function that uses visualtreeHelper in your code-bind:
private void TxtComment_PreviewKeyDown(object sender, KeyEventArgs e)
{
TraversalRequest focusRequest = null;
TextBox focusedElement = sender as TextBox;
switch (e.Key)
{
case Key.Enter:
focusRequest = new TraversalRequest(FocusNavigationDirection.Down);
if ( focusedElement != null )
{
//Move focus
bool moved = focusedElement.MoveFocus(focusRequest);
if (moved)
{
e.Handled = true;
}
}
break;
default:
break;
}
}
// find the TextBox here
private void myView_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
ListView lv = sender as ListView;
if ( lv != null)
{
ItemContainerGenerator generator = lv.ItemContainerGenerator;
ListViewItem selectedItem = (ListViewItem) generator.ContainerFromIndex(lv.SelectedIndex);
TextBox tbFind = GetDescendantByType(selectedItem, typeof (TextBox), "TxtComment") as TextBox;
if (tbFind != null)
{
FocusHelper.Focus(tbFind);
}
}
}
public static Visual GetDescendantByType(Visual element, Type type, string name)
{
if (element == null) return null;
if (element.GetType() == type)
{
FrameworkElement fe = element as FrameworkElement;
if (fe != null)
{
if (fe.Name == name)
{
return fe;
}
}
}
Visual foundElement = null;
if (element is FrameworkElement)
(element as FrameworkElement).ApplyTemplate();
for (int i = 0;
i < VisualTreeHelper.GetChildrenCount(element);
i++)
{
Visual visual = VisualTreeHelper.GetChild(element, i) as Visual;
foundElement = GetDescendantByType(visual, type, name);
if (foundElement != null)
break;
}
return foundElement;
}
One more helper to set the Focus on the TextBox:
public static class FocusHelper
{
public static void Focus(UIElement element)
{
element.Dispatcher.BeginInvoke(DispatcherPriority.Input, new ThreadStart(delegate()
{
element.Focus();
}));
}
}
It is applicable to vb.net.
Dim focusRequest As TraversalRequest = Nothing
Dim focusedElement As TextBox = TryCast(sender, TextBox)
Had a similar problem (I need my GridView to behave more like a DataGrid for my user's sanity). This is a similar take to the other solution posted here (I've reused some of those helper functions). Just name the input elements and hook-up the event handler. The code below works with Framework 4.5. If you're working with Framework 4 just change the "listView.ItemContainerGenerator.Items" references to "listView.Items".
private void FrameworkElement_PreviewKeyDown(object sender, KeyEventArgs e)
{
if (e.Key != Key.Enter)
return;
var element = sender as FrameworkElement;
if (element == null)
return;
var container = (ListViewItem)GetAnscestorByType<ListViewItem>(element);
if (container == null)
return;
var listView = (ListView)GetAnscestorByType<ListView>(container);
if (listView == null)
return;
var index = listView.ItemContainerGenerator.IndexFromContainer(container);
if (index < 0 || index >= listView.ItemContainerGenerator.Items.Count - 1)
return;
var nextItem = listView.ItemContainerGenerator.Items[index + 1];
if (nextItem == null)
return;
var nextContainer = listView.ItemContainerGenerator.ContainerFromItem(nextItem) as Visual;
if (nextContainer == null)
return;
listView.ScrollIntoView(nextItem);
var hit = GetDescendantByType(nextContainer, element.GetType(), element.Name) as FrameworkElement;
if (hit == null)
return;
Focus(hit);
}
public static void Focus(FrameworkElement element)
{
element.Dispatcher.BeginInvoke(DispatcherPriority.Input, new ThreadStart(() => element.Focus()));
}
public static Visual GetAnscestorByType<T>(Visual element)
where T : FrameworkElement
{
if (element == null)
return null;
var parent = VisualTreeHelper.GetParent(element) as Visual;
while (parent != null)
{
if (parent is T)
return parent;
parent = VisualTreeHelper.GetParent(parent) as Visual;
}
return null;
}
public static Visual GetDescendantByType(Visual element, Type type, string name)
{
if (element == null)
return null;
if (element.GetType() == type && ((FrameworkElement)element).Name == name)
return element;
Visual foundElement = null;
if (element is FrameworkElement)
(element as FrameworkElement).ApplyTemplate();
for (int i = 0; i < VisualTreeHelper.GetChildrenCount(element); i++)
{
Visual visual = VisualTreeHelper.GetChild(element, i) as Visual;
foundElement = GetDescendantByType(visual, type, name);
if (foundElement != null)
break;
}
return foundElement;
}
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