Method addChild

UnitTests/TestApp/Data.cpp:68–75

	}

	void Data::addChild(Data* _child)
	{
		MYGUI_ASSERT(_child != nullptr, "Child is nullptr");
		MYGUI_ASSERT(_child->getParent() == nullptr, "Child already attached");

		mChilds.push_back(_child);
		_child->mParent = this;
	}

	void Data::removeChild(Data* _child)
	{