Hello, I am facing a problem with our Wicket 8.10.0 application and I wonder if it's a bug or if I am using the MetaData feature in an unsupported or wrong way.
I have a Behavior, which adds a MetaData entry to a component in the Behavior's "onConfigure(Component component)" method and later removes the same MetaData again from the component in the Behaviour's "detach(Component component)" method. (I'll skip explaining what it is used for, but if it's important to understand my use case I'll gladly explain it) Now upon detaching the component with said Behaviour, Wickets NotDetachedModelChecker encountered a not detached model in the component. After debugging the problem for a few hours I discovered the cause: Right before the detach phase starts, the components internal "data" field is an array with the following 4 entries: - [0] the component's Model - [1] the MetaDataEntry belonging to the described Behavior - [2] the Behavior itself - [3] an AttributeModifier with a StringResourceModel When the component's "detach()" method is called by Wicket, it internally calls the static "Behaviors.detach(Component component)" method. This method then iterates through all the entries in the aforementioned "data" array and detaches them, if they are Behaviours. Now when it detaches the Behavior (index 2), the MetaDataEntry (index 1) gets removed as well by our Behavior, shifting every entry in the data array by 1. The next loop iteration for index 3 then doesn't find anything anymore, since the AttributeModifier, which still needed to get detached, is now at index 2 and not 3 anymore, ultimately resulting in the observed error from the NotDetachedModelChecker. To fix the problem for now I set the MetaDataEntry to a known non-null "undefined" value in the Behavior's "detach(Component component)" method and then compare that value again in the Behavior's "onConfigure(Component component)" to treat it as null. Now I wonder, if you would consider this being a bug, if I'm just using it the wrong way or if I should rather save the information in a different way, like for example in a map (Component mapped to value) in the RequestCycle object. Thanks for your help Daniel --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@wicket.apache.org For additional commands, e-mail: users-h...@wicket.apache.org
