button.cpp

void GUI::Button::activate()
{
	GUI::Component::activate();

	if(mIsToggle)
		mSprite.setTexture(mPressedTexture)

	if (mCallback)
		mCallback();

	if(!mIsToggle)
		deactivate();
}

void GUI::Button::deactivate()
{
	GUI::Component::deactivate();

	if(mIsToggle)
		mSprite.setTexture(mNormalTexture);
}

usage.cpp

auto backButton = std::make_shared<GUI::Button>(fontHolder, textureHolder);
backButton->setText("Back");
backButton->setCallback([this]() {
  mStateStack.pop();
});

auto moveLeftBindingLabel = std::make_shared<GUI::Label>(KeyBindings::getName(Player::MoveLeft), fontHolder);

auto moveLeftBindingButton = std::make_shared<GUI::Button>(fontHolder, textureHolder);
moveLeftBindingButton->setText("Move Left");
moveLeftBindingButton->setToggle(true);
moveLeftBindingButton->setEventCallback([moveLeftBindingLabel, moveLeftBindingButton](const sf::Event& event) {
  if(event.type == sf::Event::KeyReleased)
  {
    Player::setBinding(event.key.code, Player::MoveLeft); // <--- Pseudo code
    moveLeftBindingLabel.setText(KeyBindings::getName(Player::MoveLeft)); // <--- Pseudo code
    moveLeftBindingButton.deactivate();
  }
});

mGUIContainer.pack(backButton);
mGUIContainer.pack(moveLeftBindingLabel);
mGUIContainer.pack(moveLeftBindingButton);

// Without setEventCallback and manage it in the same state.
auto moveLeftBindingButton = std::make_shared<GUI::Button>(fontHolder, textureHolder);
moveLeftBindingButton->setText("Move Left");
moveLeftBindingButton->setToggle(true);
moveLeftBindingButton->setCallback([this]() {
  mIsbindingKey = true;
});