Possible null reference argument for parameter 'learningContent' in 'LearningElementPe.LearningElementPe(string name, ILearningContentPe learningContent, string description, string goals, LearningElementDifficultyEnum difficulty, ElementModel elementModel, int workload = 0, int points = 1, double positionX = 0, double positionY = 0)'.

Non-nullable property 'StoryEle1' must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring the property as nullable.

Non-nullable property 'StoryEle2' must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring the property as nullable.

Non-nullable property 'Ele1' must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring the property as nullable.

Dereference of a possibly null reference.

Non-nullable field '_itemList' must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring the field as nullable.

Possible null reference argument for parameter 'path1' in 'string Path.Combine(string path1, string path2, string path3)'.

Non-nullable property 'Foo' must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring the property as nullable.

Non-nullable property 'Foo' must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring the property as nullable.