1. A method of monitoring a graphical interface in a computer system of an aircraft cockpit, comprising the display of a graphical interface of a client application on the basis of a tree structure of graphical interaction objects composing said graphical interface, said method being characterized in that it comprises the following steps: obtaining a plurality of graphical interaction objects having a tree-structure organization; creating and adding, to said obtained tree structure, at least one new graphical interaction object defining a critical graphical display zone; modifying the tree-structure dependency of at least one critical graphical interaction object, of the obtained tree structure to make it dependent from the new graphical interaction object defining the critical zone; and performing critical monitoring only of the critical graphical objects attached to the critical zone.