Hi Chris, thanks so much for taking the time to reply in such detail. I think controllers are going to take me a little more time to understand but you've certainly made a good dent in it for me which is good. Your recommendation of the web2py manual is a good idea and given that its quite cheap I think i'll take it up. The trial version seems pretty good so i'll get the full version too!
I was taking a look through the api documentation, though interesting, still a bit over my head. I guess I shall get going with building that blog, lemme see how I go, I guess I'll be back here with any questions! Thanks again Michael Gardner On Jan 17, 9:32 pm, cjparsons <[email protected]> wrote: > Hi Mick > > I'm far from being an expert but I'll try and be helpful.. > > web2py follows the Model-View-Controller arrangement for web > applications. This approach is now common in many web frameworks > because it allows you to separate different aspects of the > application. In a large project they might be worked on by different > people with different skills, somewhat independently of each other. > > Model - the way the data that's stored by the application is arranged > (could be done by a database specialist) > View - the way the web application looks and interacts with the user > (web design & javascript specialist) > Controller - all the 'program' that sits between the Model and the > View, getting the right data for the user to see, allowing them to > fill in forms etc. and storing new information back into the database > (programming specialist) > > Controller functions have a view associated with them. Generally > controllers will get some information from the database and present it > to the user (by passing it to the view). Part of this might be a form > that allows the user to add more information to the database or update > information. The controller will handle the contents of the form and > update the database using information defined in the model. > > In the example 'db' is a variable that is called to access the > database (as set up in the model file). I wouldn't worry too much > about what is happening behind the scenes for now - if you use the > examples with your own example application you should see get a feel > for how to use the framework. > > For example to take one of the simpler example controller functions: > (as typed here might have copying mistakes) > > def show(): > id=request.vars.id > recipes=db(db.recipe.id==id).select() > if not len(recipes): redirect((URL(r=request,f='recipes')) > return dict(recipe=recipes[0]) > > This function is called when the user > visitshttp://my.application.com/show?id=1 > > The variable 'request' contains information that came from the user's > web browser. > The 'id' variable passed at the end of the URL is stored in another > variable, 'id', just as shorthand to make the rest of the function > simpler. > the 'recipes=' line executes a select query on the database, fetching > the recipes that have 'id' = 1 and putting the resulting rows into the > variable 'recipes'. > ''if not len(recipes)...' checks that at least one row was returned. > If no rows were returned then the user is redirected to a page listing > all recipes. The 'redirect' function uses an exception that means the > show() function is quit at this point and the next line won't be > processed in this case. > Finally the 'return' passes the recipe information to the view as a > dictionary. The view will be constructed to know how to present the > different recipe fields. > > Like other frameworks, web2py gives you a set of tools that add web- > related functionality (or an API). To use it you need to learn what > tools are available and how to use them together, but not necessarily > what is going on behind the scenes. > > The cookbook is good, but contains a lot less description and > information than the web2py manual, which is available in PDF form for > a very reasonable pricehttp://www.lulu.com/content/4968879 > > Chris > > On Jan 16, 11:30 pm, mickgardner <[email protected]> wrote: > > > Hi there, > > > firstly wanted to say thanks to the developers for building such a > > fantastic and easy to use web framework i especially like the > > intuitiveness of the design and web application development > > interface. > > > Secondly, an introduction and some questions. > > > I've been trying to learn django for a few weeks now by way of > > building my own blog. I got to a decent stage where the blog would > > actually be functional but I was constantly troubled by the django > > 'newforms'. Its honestly a dazzling array of functions and code that > > was beyond my ability to learn. > > > I've recently undertaken at the age of 32/33 to teach myself > > programming, having been in the web and IT industries for over ten > > years as an analyst. I've got to the stage where I can build a few > > decent console python applications & scripts, use classes, modules, > > and create functions - and have a basic level understanding of object > > oriented programming. > > > But django newforms was just beyond me! > > > Enter Web2py, I've been working through the cookbook plus pdf file. I > > got to page 11/12 "creating functions(Actions" and hit a small road > > block: > > > Question: how does one learn how to build / develop / understand the > > controllers? I looked at the code in 11/12 and wondered what it meant > > exactly, this may be slightly made worse by the fact that the db in > > the example is actually called 'db'. Was there a function called 'db' > > in the code provided? How does one best learn to develop the > > controllers and learn what the various functions in the example are? > > > Thanks for getting this far in your reading :-) > > > I hope I can learn from you all in some way and help contribute if I > > can. > > > Kind regards > > > mickgardner --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "web2py Web Framework" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/web2py?hl=en -~----------~----~----~----~------~----~------~--~---
