I'm not quite sure of your requirement but this may help: 
sub startElement {
    my( $parseinst, $element, %attrs ) = @_;
    SWITCH: {
        # ...
        if ($element eq "step") {
            my $command = $attrs{command};
            $command =~ s/\s+//g; # get rid of spaces
            if ($command eq 'LaunchApp') {
                MyModule::LaunchApp(%attrs);
            }
            elsif ($command eq 'Changemode') {
                MyModule::Changemode(%attrs);
            }
            # and so on for each command
            last SWITCH;
        }
    }
}

# This is your functions module

package MyModule;

sub LaunchApp {
    my %attrs = @_;
    print "\n----\nIn Sub MyModule::LaunchApp\n";
    for my $attr (keys %attrs) {
        print "$attr: $attrs{$attr}\n";
    }
    print "Leaving Sub MyModule::LaunchApp\n----\n";
}
sub Changemode {
    my %attrs = @_;
    print "\n----\nIn Sub MyModule::Changemode\n";
    for my $attr (keys %attrs) {
        print "$attr: $attrs{$attr}\n";
    }
    print "Leaving Sub MyModule::Changemode\n----\n";
}
1;

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In reply to Re: Using function modules and passing arguments by parsing an XML. by tangent
in thread Using function modules and passing arguments by parsing an XML. by balajinagaraju

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