I have been working on this issue for a day now and I can't figure it out.
I have a list of data which is displayed in a gui, I allow you to search for items, and if something is found it pops up a new window and populates the new list with the found items and draws the gui. I have a listener for the list so if you double click it, it opens another gui which allows you to edit the chosen item. My problem is changing the list in the original window and I am not quite sure how. I also supply a delete option in this final window, I tried passing along the original list to edit window, removing the item from that list and my plan is to update the original window with this new list. I really can't figure it out, Im sorry if I am confusing, I am having a hard time trying to think this problem out.
I defined a method called refresh in the original gui which is designed to take a vector and set the guis vector to the input and update a list and this is where I am getting the null pointer exception. I tried creating an instance of the original window and refresh on it with the new list. I can post code, but it's about 1000 lines and fairly sloppy since this is my first big project. I apologize if I am being unclear. I am trying my best to solve this problem and can't seem to think of any workable solution.