(self, mode, callback)
return cbname
Define a trace callback for the variable.

        MODE is one of "r", "w", "u" for read, write, undefine.
        CALLBACK must be a function which is called when
        the variable is read, written or undefined.

        Return the name of the callback.

        This deprecated method wraps a deprecated Tcl method that will
        likely be removed in the future.  Use trace_add() instead.
Define a trace callback for the variable.
Define a trace callback for the variable .
def trace_variable(self, mode, callback):
        """Define a trace callback for the variable.

        MODE is one of "r", "w", "u" for read, write, undefine.
        CALLBACK must be a function which is called when
        the variable is read, written or undefined.

        Return the name of the callback.

        This deprecated method wraps a deprecated Tcl method that will
        likely be removed in the future.  Use trace_add() instead.
        """
        # TODO: Add deprecation warning
        cbname = self._register(callback)
        self._tk.call("trace", "variable", self._name, mode, cbname)
        return cbname
def trace_variable ( self , mode , callback ) : # TODO: Add deprecation warning cbname = self . _register ( callback ) self . _tk . call ( "trace" , "variable" , self . _name , mode , cbname ) return cbname