AddAndMakeVisible and pointers

[StrangeMan]

Hello!

I have the following problem: A Component is used to display a list of "addons" in a custom list box. When the user clicks an item in the list, I want to display some addon-specific options next to the list. The list holds references to these addons anyway so i thought, it might be a good idea to implement a member function for each addon like this:

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std::shared_ptr<Component> Addon::getGuiPage();

So now, when the user clicks the list, i'd like to let the addon create it's gui component so I can add it to my window using "addAndMakeVisible". I call it like this:

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addAndMakeVisible(someAddon->getGuiPage().get());

However, nothing happens. I guess, it's got to do with the whole shared_ptr stuff, but I have no idea, whats going on here. Please, can you help me?

Thanks a lot,
StrangeMan

[jules]

Well yes.. Your shared_ptr will immediately delete the component when it goes out of scope!

[StrangeMan]

ah, sorry, forgot to tell: The method stores a copy of the pointer internally like this

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class Addon
{
...
private:
   std::shared_ptr<Component> m_gui_page;
};

std::shared_ptr<Component> addon::getGuiPage()
{
   if (m_gui_page == 0)
   {
      m_gui_page = std::shared_ptr<Component>(new Gui());
   }
   return m_gui_page;
}

[jules]

Ah, well you're probably just not setting its bounds or something then.

[StrangeMan]

oh my god, that's so awkward Sometimes you won't find the problem due to it's simplicity... Of course you're right.... Well thanks then...

[X-Ryl669]

ah, sorry, forgot to tell: The method stores a copy of the pointer internally like this

That's why I usually don't tell people to use shared_ptr...
You only need a member here, not a pointer. Use a reference and you're done, you'll avoid useless referenced counting, the mind-twisting weakptr issues and so on.