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    <p>Clearing all the references to a handle class object will remove it from memory, and the <code>delete</code> method on your <code>myClass</code> will be called automatically on upon the object being destroyed. It's just unfortunate confusing terminology. Your <code>myClass</code> is an "MCOS class" or "MCOS object", not a "handle graphics object" like <code>help clear</code> is talking about. They're different things, at least at the M-code level.</p> <p>The handle graphics "objects" are not the same type of "object" that your myClass is, and the "handle graphics handle" returned by <code>figure()</code> is not the same sort of thing as the class named <code>handle</code> that you're inheriting from. That passage from <code>help clear</code> talking about "handle graphics handles" doesn't apply to your object. See <code>doc handle</code> and follow the link for the <code>delete</code> method for relevant doco.</p> <p>Don't feel bad; the Matlab doco doesn't make these distinctions very clear. (IIRC it doesn't even explicitly use the term "MCOS"; it just calls them "objects".) Basically, the material under the "Object-Oriented Programming" section in the doco is relevant to the kind of "object" and "handle" you're working on with <code>myClass</code>. The doco under "Graphics" and "GUI Development" is talking about the other handle graphics kind of "object" and "handle". I think they use the term "handle" for the handle graphics stuff and "handle class" for the OOP stuff.</p> <p>To verify that your <code>delete</code> works, just make a trivial class.</p> <pre><code>classdef myClass &lt; handle methods function delete(obj) disp('delete was called'); end end end </code></pre> <p>And then create one and clear it.</p> <pre><code>&gt;&gt; x = myClass x = myClass handle with no properties. Methods, Events, Superclasses &gt;&gt; clear x delete was called &gt;&gt; </code></pre> <p>If your destructor is not being called, there may be other references to the object lingering. The destructor doesn't get called each time a variable holding a reference to the object is cleared, only when the last variable holding a reference (or indirect reference) is cleared. </p>
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    1. POMATLAB - run object destructor when using 'clear'?
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    1. USAndrew Janke
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    1. COThere are certainly other references to the lingering object; part of the reason I would like this functionality is because I get rid of those references in my destructor. I updated the OP with the relevant information; it might not make sense without the complete context, but the complete context isn't relevant to the question in particular..
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      1. USDang Khoa
    2. COI've had similar problems, especially when creating custom GUI elements. I don't think it's possible to force the destructor to be called when you clear the variable. As you note in your question, you may want to simply call the delete method on your object before clearing it.
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    3. COJust FYI, I think it's good functionality that the destructor isn't called with clear is used in the terminal when using a gui with object oriented code (which I've mostly found to be the case). This means that if the user uses `clear` by accident, your gui won't shutdown, even if the handle to the gui is cleared from the workspace. However, if the user calls `delete` on the handle the destructor will still run.
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      1. USJustin
 

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