Lose focus on textbox when enter is pressed or clicked away - wpf

Question

I have a textbox on a canvas. How do I lose the focus (so the caret goes away) when I press enter and/or click on the canvas? My textbox is in a template for a button.
I've tried pretty much everything and it doesn't work:
FocusManager.SetIsFocusScope(mainCanvas, true)
mainCanvas.Focus();
FocusManager.SetFocusedElement(child, parent);
it is interesting that if I use a button it works with KeyBoard.Focus(button) but it doesn't work with a canvas, does anyone know why or have any other suggestion?

Answer 1

The problem with Canvas is that when you click on it, you don't actually get the click event to occur unless you have a background that is not white.
One trick if you want white is to use white -1 or #FFFFFE or if the parent is also white use Transparent. So no one can tell it isn't white.
Now your click event can occur.
Also you need to make it focusable.
MainWindow.xaml
<Window x:Class="TextBoxInCanvas.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="350" Width="525">
<Grid Name="MainGrid">
<Canvas Name="canvas1" Focusable="True" Background="#FFFFFE" MouseDown="canvas1_MouseDown">
<TextBox Height="23" Name="textBox1" Width="120" IsEnabled="True"
Canvas.Left="81" Canvas.Top="115" PreviewKeyDown="textBox1_PreviewKeyDown"/>
</Canvas>
</Grid>
MainWindow.xaml.cs
using System.Windows;
using System.Windows.Input;
namespace TextBoxInCanvas
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}
private void canvas1_MouseDown(object sender, MouseButtonEventArgs e)
{
Keyboard.Focus(canvas1);
}
private void textBox1_PreviewKeyDown(object sender, KeyEventArgs e)
{
if (Key.Enter == e.Key)
Keyboard.Focus(canvas1);
}
}
}
How to make the WPF Canvas mouse click event work?
I made a more complete post on my blog.