Having throughly blasted my foot with bullets I'm removing all the modal loops from an application.
There's a scenario I'm still scratching my head about though. In the code below if the object I'm calling the AlertWindow from is deleted before the user pushes a button on the dialog, what's the tidiest way of ensuring the callback doesn't crash (as devices will have been deleted). Do I need to use WeakReference here, or is there a less verbose solution I've missed?
I guess I could extend my ModalCallbackAction class to take a WeakReference to the originating object and then not call the lambda at all - which is a relatively nice solution.
auto callback = [this, deviceId](int r)
{
if (r == 1)
{
auto newDevice = devices.createNewObject();
newDevice->setUniqueDeviceId(deviceId);
newDevice->setConnected(true);
listeners.call(&Listener::deviceListChanged);
}
};
AlertWindow::showOkCancelBox(AlertWindow::QuestionIcon, "Attach Device", "Attach?", "Yes", "No", nullptr, new ModalCallbackAction(callback));
Where:
class ModalCallbackAction
:
public ModalComponentManager::Callback
{
public:
ModalCallbackAction(std::function<void(int)> actionToRun)
:
action(actionToRun)
{}
void modalStateFinished(int resultCode) override
{
action(resultCode);
}
private:
std::function<void(int)> action;
};