Behaviors don't work on flyouts

Question

Hi,

in my app I'm trying to using a behavior in a button flyout to invoke a command on flyout Closed event:

<Button>
	<Button.Flyout>                                                            
		<Flyout>
			<Interactivity:Interaction.Behaviors>
				<Core:EventTriggerBehavior EventName="Closed">
					<Core:InvokeCommandAction Command="{Binding MyCommand}" />
				</Core:EventTriggerBehavior>
			</Interactivity:Interaction.Behaviors>			
		</Flyout>
	</Button.Flyout>
</Button>

When I run the app I get this execption:

Cannot add instance of type Microsoft.Xaml.Interactions.Core.EventTriggerBehavior to a collection of type Microsoft.Xaml.Interactivity.BehaviorCollection.

Where is the problem? Behaviors cannot be used in Flyouts?

Answer 1

Does it work if you change the eventname to Tapped?

I found this which shows that it works:

http://windowspak.com/using-a-behavior-to-open-attached-flyouts-in-windows-8-1-store-apps/

---

Matt Small - Microsoft Escalation Engineer - Forum Moderator
If my reply answers your question, please mark this post as answered.

NOTE: If I ask for code, please provide something that I can drop directly into a project and run (including XAML), or an actual application project. I'm trying to help a lot of people, so I don't have time to figure out weird snippets with undefined objects and unknown namespaces.

Answer 2

In the sample you provided the behavior is attached to the image and not to the flyout.
I'd like to add a behavior to the flyout in order to invoke a command when the flyout is closed.

I think there is a problem with behaviors attached to flyouts.

Answer 3

Do you mind sharing a project with me?

---

Matt Small - Microsoft Escalation Engineer - Forum Moderator
If my reply answers your question, please mark this post as answered.

NOTE: If I ask for code, please provide something that I can drop directly into a project and run (including XAML), or an actual application project. I'm trying to help a lot of people, so I don't have time to figure out weird snippets with undefined objects and unknown namespaces.

Answer 4

Here you can find a sample application to reproduce the problem:

https://skydrive.live.com/redir?resid=9254CCAFCE7EE400!7680&authkey=!AAmf04PB-HQ0B9M&ithint=file%2c.zip

Answer 5

it's not the flyout. I had the same problem in the Datatemplate of a listview. I moved it from the datatemplate to the Listview itself, and ik was allright.

Answer 6

Is it possible that behaviors work only with elements that inherit from Control class?

Popup inherits from FrameworkElement and beahviors don't work.
Button inherits from Control and behaviors work.

Answer 7

I've been working on this and what you're saying appears to be correct.

---

Matt Small - Microsoft Escalation Engineer - Forum Moderator
If my reply answers your question, please mark this post as answered.

NOTE: If I ask for code, please provide something that I can drop directly into a project and run (including XAML), or an actual application project. I'm trying to help a lot of people, so I don't have time to figure out weird snippets with undefined objects and unknown namespaces.

Answer 8

Hi,

also DatePicker doesn't support behaviors, I get the same exception:

Cannot add instance of type Microsoft.Xaml.Interactions.Core.EventTriggerBehavior to a collection of type Microsoft.Xaml.Interactivity.BehaviorCollection

DatePicker however inherits from Control.