Letting users customize content property of user control at run-time

Question

This is the required behaviour:

I have various controls present on the canvas e.g. Callouts (from Expression Blend .dll), or simple Labels. When the user 'double clicks' (or any other event I decide to tie in) the control should change its appearance to allow the user to edit the control's Content property. Clicking off the control should then turn it back to 'read-only' method.

Any suggestions on how this would be best achieved? Ideally I want to do this all in c# to add this behaviour to the control at runtime (as this control is added dynamically to the canvas)- and avoid XAML altogether.

I reckon I've got to do something with adorners to display a textbox bound to the control's content property on the required event, but some code samples or links elsewhere would be appreciated? :) - I haven't been able to find anything on an existing search, but I reckon it should be fairly simple.

Answer 1

Unfortunately, style triggers do not do anything with IsReadOnly and IsEnabled. You would have to do that from an event.

Here is my sample:

WPF:

<Window x:Class="StateChangingTextbox.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">

    <Window.Resources>
        <Style TargetType="TextBox">
            <Style.Triggers>
                <Trigger Property="IsMouseOver"  Value="True">
                    <Setter Property="Background" Value="#eee" />
                </Trigger>
            </Style.Triggers>
        </Style>
    </Window.Resources>

    <Grid HorizontalAlignment="Center" VerticalAlignment="Center">
        <TextBox Width="300" Height="200" TextWrapping="Wrap" IsReadOnly="True" 
            MouseEnter="TextBox_MouseEnter"
            MouseLeave="TextBox_MouseLeave"/>
    </Grid>
</Window>

Code-behind:

/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
    public MainWindow()
    {
        InitializeComponent();
    }

    private void TextBox_MouseEnter(object sender, MouseEventArgs e)
    {
        var textbox = sender as TextBox;
        if (textbox != null)
        {
            textbox.IsReadOnly = false;
        }
    }

    private void TextBox_MouseLeave(object sender, MouseEventArgs e)
    {
        var textbox = sender as TextBox;
        if (textbox != null)
        {
            textbox.IsReadOnly = true;
        }
    }
}