Kill a class instance (memory leak fix)

General
1

I have a class with a shared property array that holds instances whenever a class is added to a window.

What I did is adding a constructor, that adds the instance to the array.
I added a Destructor that removes the instance.

The problem is, that the Destructor never gets called, in this manner.
So, the stacks keeps building up…

In the class I send notification to all the instances in the array.
I do this with some introspection…invoke tricks. I just call a method in the instance that raises the notification event.

But when the window, where the instance lives, is closed… it will not be able to finish the RaiseEvent. A NillErrorExeption is raised. I checked, and indeed, there were no controls in the window that could receive the notification. In my test I added a simple “Property %PropName% Changed” to a textField.

Did I create a memory leak?

To clarify, the class I made is a new approach for configuration settings.

All the settings are managed by shared properties.
But when the class is dragged on a window or container, it can receive notifications, with events I defined in the class.
Whenever a settings is changed, it would send a notification to all the instances.

But in my test, I added this to multiple windows. And whenever I closed a window, I noticed that the Destructor wasn’t called.

2

Look into WeakRef. You can store the instances that way and it won’t prevent them from being destroyed in the normal fashion.

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3

Thanks!
I did look in into WeakRef. But I needed to cheak the WeakRef.Value for nil. That told me that the reference was out of scope.

4

That’s right. The WeakRef itself is persistent even if the object to which it refers has been destroyed.

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