// button_duplicate->signal_clicked().connect(sigc::mem_fun(*this, &studio::LayerTree::on_duplicate_pressed));
// button_encapsulate->signal_clicked().connect(sigc::mem_fun(*this, &studio::LayerTree::on_encapsulate_pressed));
// button_delete->signal_clicked().connect(sigc::mem_fun(*this, &studio::LayerTree::on_delete_pressed));
// button_duplicate->signal_clicked().connect(sigc::mem_fun(*this, &studio::LayerTree::on_duplicate_pressed));
// button_encapsulate->signal_clicked().connect(sigc::mem_fun(*this, &studio::LayerTree::on_encapsulate_pressed));
// button_delete->signal_clicked().connect(sigc::mem_fun(*this, &studio::LayerTree::on_delete_pressed));