As mentioned above, after widgets have been created (with e.g.
newButton), they will not be displayed just yet; this only happens
after they have been packed. One can use this effect by first creating
lots of widgets, and then packing them in one go, lessening the
unpleasant flicker effect occuring when the GUI is built one interface
at a time. To minimize the flickering further, use the function
which delays all Tk commands in the argument, and performs
them at once. The argument then consists of a sequence of
pack commands. Unfortunately, the flickering effect cannot be
totally eliminated.
Packing in particular determines the visual layout of the GUI by the order in which the widgets are packed, and by packing options. Tk's know different packing algorithms (or geometry managers, in Tk parlance); of these, HTKsupports the pack geometry manager, and the grid geometry manager. The third, the place geometry manager, could easily be added, if you are so inclined.