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Christoph J. Bachinger

redraw

How can I redraw a Window,
for example automatically all 10 seconds?

Thanks,
Katjana

Blair McGlashan-2

Re: redraw

Katjana

You wrote in message news:[hidden email]...
> How can I redraw a Window,
> for example automatically all 10 seconds?

Well one easy way is to set up a timer to invalidate it every 10 seconds.
There are a couple of ways to do this:

1) Use a background process, for example, refreshing every 5 seconds:
p := ClassHierarchyDiagram show.

invalidater := [[Processor sleep: 5000. p isOpen] whileTrue: [p view
invalidate]] fork

2) Use a Windows timer, as in the ProcessMonitor (if you have DSE or above).

I would tend to faviour the latter for a task like this, since it makes
sense to tie the lifetime of the refresh operation to the window, and also
this will avoid any synchronisation issues. You'll be safe just invalidating
a view from a background process, but should you decide you want to do
something else for the refresh, e.g. repopulating a list, then you'll need
to consider the usual thread synchronisation issues, all of which can be
avoided by using a Windows timer.

Regards

Blair

Christoph J. Bachinger

Re: redraw

Thank you very much! :-)

Blair McGlashan schrieb:

> Katjana
>
> You wrote in message news:[hidden email]...
>
>>How can I redraw a Window,
>>for example automatically all 10 seconds?
>
>
> Well one easy way is to set up a timer to invalidate it every 10 seconds.
> There are a couple of ways to do this:
>
> 1) Use a background process, for example, refreshing every 5 seconds:
> p := ClassHierarchyDiagram show.
>
> invalidater := [[Processor sleep: 5000. p isOpen] whileTrue: [p view
> invalidate]] fork
>
> 2) Use a Windows timer, as in the ProcessMonitor (if you have DSE or above).
>
> I would tend to faviour the latter for a task like this, since it makes
> sense to tie the lifetime of the refresh operation to the window, and also
> this will avoid any synchronisation issues. You'll be safe just invalidating
> a view from a background process, but should you decide you want to do
> something else for the refresh, e.g. repopulating a list, then you'll need
> to consider the usual thread synchronisation issues, all of which can be
> avoided by using a Windows timer.
>
> Regards
>
> Blair
>
>

Chris Uppal-3

Using private methods from base system (was: redraw)

In reply to this post by Blair McGlashan-2

Blair,

> 2) Use a Windows timer, as in the ProcessMonitor (if you have DSE or
> above).
>
> I would tend to faviour the latter for a task like this

Incidentally, View>>setTimer:interval: is still private. I believe you once
said that you intended to make it public.

Oh, and more incidentally still, is Bitmap>>canvas really intended to be
private -- I find that I've had to use it in several places ? Am I missing
something ?

Would it help if I/we tried to identify all the private base-system methods
that we call because we believe we have to (either because there's no
alternative or because it seems the best man for the job)? E.g. my FMB used to
call CompiledCode>>refersTo: but that was replaced by
CompiledCode>>refersToLiteral: in 5.1. Since it was a private method, I
couldn't very well complain that it had changed without warning, but I'd like
to be able to avoid such problems where possible (and within reason).

-- chris

Blair McGlashan-2

Re: Using private methods from base system (was: redraw)

Chris

You wrote in message news:3eddc635$0$45186$[hidden email]...
> Blair,
>
> > 2) Use a Windows timer, as in the ProcessMonitor (if you have DSE or
> > above).
> >
> > I would tend to faviour the latter for a task like this
>
> Incidentally, View>>setTimer:interval: is still private. I believe you
once
> said that you intended to make it public.
>
> Oh, and more incidentally still, is Bitmap>>canvas really intended to be
> private -- I find that I've had to use it in several places ? Am I
missing
> something ?

These will be made public in PL2 (along with View>>killTimer:).

> Would it help if I/we tried to identify all the private base-system
methods
> that we call because we believe we have to (either because there's no
> alternative or because it seems the best man for the job)?
>...

Yes, it would help.

Regards

Blair