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> Germán,
>
> > Someone know some examples of a similar thing where I can see for some
> > ideas?
>
> I've just put together a package (which needs Dolphin 5.0.3) that might
> give you some ideas.  You can download it from
>
> http://www.idb.me.uk/files/lapper.zip  (about 4K)
>
> Just evaluate "Lapper show" to run it.
>
> --
> Ian
>

> Germán,
>
> > Someone know some examples of a similar thing where I can see for some
> > ideas?
>
> I've just put together a package (which needs Dolphin 5.0.3) that might
> give you some ideas.  You can download it from
>
> http://www.idb.me.uk/files/lapper.zip  (about 4K)
>
> Just evaluate "Lapper show" to run it.
>
> --
> Ian
>

> Germán,
>
> > 1) Why not a model? It's possible to think in a complete app (small
> > like this) without a model?.
>
> Yes, there is nothing that says that you _have_ to have a Model
> associated with the View and Presenter.  In this case it isn't really
> needed and would just add extra complexity.
>
> If you were to add more functionality, ways of saving and comparing sets
> of lap times for example, then that might make a better case for using a
> model (or models).
>
> > 2) I think that i've understood the process and fork, are to update
> > each 50 milliseconds the display, without bother the main process
> > (which is measuring the time)? (That was mi problen in my original
> > code).
>
> Yes.  It just uses the system timer (Time>>millisecondClockCount) to do
> the low level timing.  The forked loop just provides an interrupt every
> 50mS that updates the display - it is not involved in the actual timing
> at all.  You could change the loop delay so that it only updated the
> display every second and you would still get mS precision for the lap
> times.
>
> When you press "start" it just remembers the current mS clock value and
> starts updating the display with the elapsed time (current count - start
> count) every 50mS
>
> When you press the 'lap' button it grabs the current mS count, works out
> the elapsed time and adds it to the lap list and then resets the saved
> start time to the new value.   The display updates continue but now
> start showing the time that has elapsed (current count - start) since
> the button was pressed.
>
> When you press "stop" the final elapsed time is added to the list and
> the 50mS loop terminated, resulting in the end of the display updates.
>
> Note that the display update process can be killed in three ways
> - pressing the stop button
> - when the view is closed (for when the user closes the view with the
> timer running)
> - when the Lapper instance is finalized (for when a running timer
> crashes and leaves a zombie view).
>
> It's better to be as sure as you can be that forked processes are always
> terminated as it can lead to some annoying walkbacks if you leave one
> running without a visible view, although you can always use the
> ProcessMonitor tool if you need to.
>
> > 3) QueryCommand: I don't well understand how and where you are using
> > this method.
>
> It's part of Dolphins built in mechanism for handling the enabling and
> disabling of buttons (or, to be more exact, the commands sent by buttons
> and menus).  There have been a number of discussions about this in the
> newsgroup so you might like to search the archive for #queryCommand.
>
> FWIW, There was one small omission in that method.  The test for the
> #clear command should read
>
> command == #clear
>  ifTrue:
>   [aCommandQuery isEnabled: process isNil & historyP list notEmpty.
>   ^true].
>
> as you only want to enable the clear button if the timer is stopped
> _and_ there is actually some data to clear.
>
> > 4) GUI: I must to learn much more, by example ListView, layout
> > managers, etc. Some recommnedations about places where to read about
> > using all elements of view composer?.
>
> Ted Bracht has written a book that talks you through creating a complete
> application using Dolphin and is based around a Formula 1 motor racing
> theme so it might be doubly useful to you.  It's probably worth while
> you trying to locate a copy.
>
> In the meantime my recommendation would be to just have a play with the
> ViewComposer.  Create some _simple_ applications and add things like
> ListViews, Edit, Buttons and the like.  You should also have a look at
> the example sample applications that Dolphin provides.  If you get stuck
> then ask about the specific issue here in the newsgroup - I'm sure
> someone will be able to point you in the right direction
>
> Once you get used to it the Dolphin ViewComposer is not, in my opinion,
> particularly difficult to use and can be quite powerful.
>
> --
> Ian
>