[Lazarus] GUI development for web UI

michael.vancanneyt at wisa.be michael.vancanneyt at wisa.be
Wed Nov 24 13:18:02 CET 2010

On Wed, 24 Nov 2010, Michael Schnell wrote:

> On 11/24/2010 11:42 AM, michael.vancanneyt at wisa.be wrote:
>> I tried making moderatly complicated production applications with it. It 
>> cannot be done without redesigning ExtPascal from the ground up.
> Same here, That is why I only recommended it as a way to try out ExtJS.
>> Comet is a rickety technology. Not robust at all, and creates more problems
>> than it solves. You can use polling, but that's just plain HTTP, not even
>> worth of putting a name on it.
> I suppose a problem of Comet's is that it needs cooperation of the web 
> server, allowing for an appropriate number of simultaneous "hanging" 
> requests.

Not only that, but also switches, routers, firewalls and proxies.

> In fact the necessity of  using such questionable technology as a 
> workaround for the missing server event transport is a design flow of the 
> abysmal http protocol which never was intended for but needs to be abused for 
> this kind of applications due to the incompetence of most IT departments that 
> are not able to decently configure the firewalls.

I think any technology which relies on a persistent connection is bound to
fail. Not because the concept is inherently bad, but because in practice, a
connection is rarely persistent.

We've had this discussion before.

> I wonder what technology Silverlight/Moonlight uses for this purpose. Could 
> this be a hint for an upcoming "HTML" Widget Type ?

I doubt that any technology which relies on browser plugins will make it.
HTTP/Html/Javascript are the only reliable standards (and even then) worth
working on.

All the rest is risky and thus - in my book - not even worth considering.
(not to mention the vendor lock-in they cause).


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