I have seen an app on OSX that show as below:
And i can see the control structure by the UIElementInspect tool.
From the screenshot, we can see that there is a big NSTextField, and it has so many small sub NSTextField, each sub NSTextField can be clicked, edit and remove by mouse or key event. I want to implement the same function, but i can not put a NSTextField to the subview of another NSTextField. Who can tell me how to implement the similar function.