[Lazarus] GUI development for web UI

ABorka fpc-devel at aborka.com
Wed Nov 24 19:00:51 CET 2010

On 11/24/2010 03:11, michael.vancanneyt at wisa.be wrote:
> On Wed, 24 Nov 2010, ik wrote:
>> On Wed, Nov 24, 2010 at 12:46, <michael.vancanneyt at wisa.be> wrote:
>>>>> I did some research on that some months ago. I found that this
>>>>> supposedly
>>>>> best would be done using "ExtJS".
>>>> There are few problems with ExtJS. First it's not open source if you
>>>> wish
>>>> to
>>>> use it in commercial apps (dual license is complicated).
>>> What is the problem with buying a license if you make a commercial
>>> product
>>> ?
>> There are a lot of issues with it. Let's take MySQL for example, If you
>> connect to it in a commercial app, then you require to buy a commercial
>> license, but if you release the connection code it's GPL, however if
>> you are
>> using Connector/J or ConnectorC, you do not have to, and so does with
>> PHP.
>> Now If I use the FPC connection code (it's open source and available for
>> all), do I require to release my code that works with MySQL or not ? I
>> really do not know the answer here...
>> Now if I build a web app for my clients and they have the source code,
>> do I
>> require to buy a commercial license of ExtJS ?
> Yes, because you make money on it, it is not open source.
>> If I use some sort of "binding" for the code of ExtJS, that is my own API
>> for the their code and release it in OpenSource, does a commercial web
>> app
>> that uses it, should buy a commercial license ?
> Yes, because they use ExtJS.
>> It's not that simple as it sounds, and hence, it complicate everything,
>> there are many scenarios that are not that simple to understand what you
>> should do (in open source, and in commercial, so when it's dual license,
>> it's even harder).
> I agree that dual-license is tricky, but that has never stopped me from
> using a toolkit, if it is good.
> MySQL I simply don't use because it is a bad database engine :-)

I think you guys are not exactly correct regarding the ExtJS license.


"According to the linked ExtJS licensing FAQ, you have obligations to 
publish the ExtJS JavaScript code that YOU have modified AND(!) you are 
distributing it. So, in-house projects are excluded by default, as well 
as all extensions you have downloaded from the Internet - since those 
are already published back to the community. As I've noted, I never 
needed to extend ExtJS so far, always found that someone else did what I 
needed already.
Either case, it does not affect your FPC/Lazarus project parts."

In my opinion ExtJS is absolutely the best framework to use on the 
client side GUI within a browser, and Lazarus/FPC 100% supports it right 
now (0.9.29/2.51). You do not need ExtPascal or any other additional 
libraries to build superb systems with it.
You do not need to buy ExtJS licenses either.

As for MySQL usage...I do not have any problem with using that either in 
my web projects (Im using ZEOS library to access the DB). It is still by 
far the most used and available DB for web apps/web servers.


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