[WICKET-5538] When using Component.setDefaultModel, only detach the previous model if the new one is different

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 7.0.0-M1, 6.15.0
• Component/s: wicket
• Assignee: Martin Tzvetanov Grigorov
• Reporter: Guillaume Smet
• Created: 19/Mar/14 16:54
• Updated: 24/Mar/14 08:37
• Resolved: 24/Mar/14 08:37

Description

From my post on the list:

Hi,

I don't see the point of detaching the prevModel if the model is not changing.

I was thinking about changing the logic of Component.setDefaultModel like that:
public Component setDefaultModel(final IModel<?> model)
{
IModel<?> prevModel = getModelImpl();

IModel<?> wrappedModel = prevModel;
if (prevModel instanceof IWrapModel)

Unknown macro: { wrappedModel = ((IWrapModel<?>)prevModel).getWrappedModel(); }

// Change model
if (wrappedModel != model)
{
// Detach current model only if we really change the model
if (prevModel != null)

Unknown macro: { prevModel.detach(); }

modelChanging();
setModelImpl(wrap(model));
modelChanged();
}

return this;
}

Note that it's something that hurts us a lot in a particular pattern
we have here. We change the default model in onConfigure and every
time we do it it's detached even if it's the exact same model.

We could add a check in our code but I'm thinking it could be better
to do it in Wicket directly.

Thoughts?