Getting JUCE Message Thread (1): EXC_BAD_ACCESS

Development
1

Getting this error in JUCE when trying to abstract away the buttonClicked handler.

My code looks like this:

Button.cpp/h

    class Button : public juce::Button::Listener,
                  public BaseComponent,
                  public juce::TextButton
    {
    public:
      Button(
          std::string,
          double,
          double,
          BaseHandler *);

      void buttonClicked(juce::Button *) override;
    };

    void Button::buttonClicked(juce::Button *btn)
    {
      // This is where the error happens
      handler->handle(this);
      // or handler->handle(btn);
    }

And this is how the BaseHandler and a concrete handler look like:

    class BaseHandler
    {
    public:
      BaseHandler();
      virtual void handle(juce::Component *) = 0;
    };

    void PlayHandler::handle(juce::Component *)
    {
      std::cout << "From operator" << std::endl;
    }

The error happens when invoking the handle method in Button::buttonClicked(). This is how I instantiate a button:

    PlayHandler ph;
    buttons.push_back(new Button("Play", 80, 40, &ph));

Why would I be getting “JUCE Message Thread (1): EXC_BAD_ACCESS (code=1, address=0x358001a9f48094)” here? I did this exact same thing but with lambdas instead of the BaseHandler implementation, and it was working fine.

2

Looks like your PlayHander is created on the stack, which will then go out of scope and therefore you hold a dangling pointer to &ph and the code explodes when trying to dereference it.

1 Like
3

Also this looks like an overcomplicated design.

For each juce button instance, you can set the onClick member functional to do whatever you want without the need for subclassing