Data binding to a UserControl in WPF

Question

I have a UserControl that I want to participate in data binding. I\'ve set up the dependency properties in the user control, but can\'t get it work.

The uc displays the

Answer 1

I know this is an old topic but still.

Also mention the PropertyChangedCallback on the UIPropertyMetadata during registering your DP

Answer 2

Possibly you need to add to your property FrameworkPropertyMetadata where specify FrameworkPropertyMetadataOptions.AffectsRender and AffectsMeasure.

FrameworkPropertyMetadataOptions enumeration MSDN article

Answer 3

You set the DataContext in the Control to itself, thus overwriting the DataContext when using this Control in other controls. Taking your binding as example in your situation:

<src:BlueTextBox BlueText="{Binding Path=MyString}" /> 

Once loaded and all the Datacontext is set, it will look for the path MyString in your BlueTextBox thing control due to you setting the DataContext to it. I guess this is not how you intended this to work ;).

Solution:

Change the text binding either one of the 2 bindings:

{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type src:BlueTextBox}}, Path=BlueText}

or

Name your control Root (or something like that)

<UserControl x:Name="Root"

{Binding ElementName=Root, Path=BlueText}

And remove the

DataContext = this;

from the constructor of your UserControl and it should work like a charm..

Answer 4

I think in this case you need to set the ElementName property in the binding. Something like this:

<UserControl x:Class="Binding2.BlueTextBox" x:Name="blueTextBox"...
<Grid>
    <TextBox x:Name="myTextBox" Text="{Binding ElementName=blueTextBox, Path=BlueText}" Foreground="Blue" Width="100" Height="26" />
</Grid>