About

Interface implementations stored at a registry are used by accessing the component class with the given maxon::Id from the registry. Then it is possible to create a reference class instance to use the implementation.

Registry Access

Registries are based on the maxon::Registry class. A given element stored in a registry is identified with a maxon::Id.

maxon::Registry::GetEntries(): Returns an iterator over all registered elements.
maxon::Registry::GetEntriesWithId(): Returns an iterator over all registered elements (class and ID).
maxon::Registry::Find(): Returns a pointer to the element with the given ID or nullptr.
maxon::Registry::Get(): Returns the element registered with the given ID.
maxon::Registry::Insert(): Registers an element with the given ID.
maxon::Registry::Erase(): Removes the element with the given ID.

  // This example creates a reference object from the registry with the given ID.
  // get the class with the given Id from the registry "ColorClasses"
  const maxon::Id redID { "net.maxonexample.class.colors.red" };
  const maxon::Class<ColorRef>* const componentClass = ColorClasses::Find(redID);
  if (componentClass == nullptr)
    return maxon::UnexpectedError(MAXON_SOURCE_LOCATION, "Could not get color."_s);
  // create reference object
  const ColorRef color = componentClass->Create() iferr_return;
  // use reference object
  const maxon::String  colorName = color.GetName();
  const maxon::Color32 colorRGB  = color.GetRGB();
  DiagnosticOutput("Color Name: @", colorName);
  DiagnosticOutput("Color RGB: @", colorRGB);

One can also simply loop through all elements with maxon::Registry::GetEntries():

  // This example loops through all component classes known to the given registry.
  for (const auto& it : ColorClasses::GetEntries())
  {
    // get class
    const maxon::Class<ColorRef>& componentClass = it;
    // create reference object
    const ColorRef color = componentClass.Create() iferr_return;
    // use reference object
    const maxon::Id&     eid = it.GetId();
    const maxon::String  colorName = color.GetName();
    const maxon::Color32 colorRGB  = color.GetRGB();
    DiagnosticOutput("ID: @", eid);
    DiagnosticOutput("Color Name: @", colorName);
    DiagnosticOutput("Color RGB: @", colorRGB);
  }

Table of Contents

About

Registry Access

Further Reading