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A new CheckBox component in Streamlined

2008-07-04T16:43:00Z

I’ve noticed that Streamlined when display has_and_belongs_to_many or has_many relationships in an edit view calls ‘Streamlined::Components::Select’ (lib/streamlined/column/association.rb line 123). That class simply render a ‘select’ tag with multiple choices.

I created a new component that can be called instead the standard one. It’s called CheckBox and it displays, as the name may suggest, a checkbox for each choice available.

To add this component simply create a new file under ‘lib/streamlined/components’ called ‘checkbox.rb’ and paste the same content of ‘select.rb’ except these two changes:


    # line 15
    class CheckBox
    REQUIRED_ATTRS = [:view, :object, :method, :choices, :item]

    # Substitute the render method with this 
    def render
      ids = item.send(Inflector.pluralize(method.to_s)).collect{|b| b.id}
      name = "#{object}[#{method}][]" 
      choices.collect do |c| 
        view.check_box_tag(name,c[1],ids.include?(c[1])) + "#{c[0]}" 
      end.join("<br/>") + view.hidden_field_tag(name, STREAMLINED_SELECT_NONE)
   end

Remeber also to include this new file (from lib/streamlined/components.rb) and change the line 123 in association.rb to call this new component:


      result = Streamlined::Components::CheckBox.render do |s|
        s.view = view
        s.object = model_underscore
        s.method = name
        s.choices = choices
        s.options = {:selected => selected_choices }
        s.html_options = {:size => 5, :multiple => true}
        s.item = item
      end

Sandro

Ruby on Rails & Maths...

2008-07-01T08:30:00Z

I have always been fascinated with Mathematics and how you can solve problems using it, we all know that in programming it is very useful. I recently had to use maths in a layout that I needed to incorporate for a new application…

Problem:

I had to display a dynamic list of suburbs in a table, that was an x amount of rows and had 3 columns.

Solution:

I used Mod (the mathematical arithmetic that gives you the remainder of the division).

Therefore:


<table>
<% r = 0 %>
<% @count_suburb.each do |c| %>
<% area = Area.find_by_code(c[0])%>

<% if ((r % 3) == 0)  %>
<tr>
<% end %>
<% r += 1%>

<td>Write something here....<%= c.name.capitalize  %></td>

<% if ((r % 3) == 0)  %>
</tr>    
<% end %>

<% end %>
</table>

Does anyone know of a better solution?

Thanks Annalisa

Advanced statements with Ruby

2008-06-27T09:06:00Z

Yesterday I was playing with statements trying to find out an elegant way to solve a problem:

The problem

While reading from an Excel file (using the Parseexcel gem) I needed to get a value from the 3rd column or from the 2nd (if the third is empty). Plus I had to execute an additional operation only if the value I got came from the second column. ( value / 100 )

The Solution

Parseexcel lets you scan your Excel worksheet by rows. Each row makes its value available through the ‘at(pos)’ method where pos is the index of the column (starting from 0). This is the solution I come across:


worksheet.each(3) do |row| 
        break if ((value=row.at(2)).nil? and (div=true;value=row.at(1)).nil?)
        value = value.to_i / 100 if div
        # other code ...
end

Conclusion

By using this trick I was able to detect when the assignment come from the second or the third column (remember that when the first condition in an ‘and’ clause isn’t met the interpreter doesn’t execute the second, thus div remains nil if row.at(2) is not nil).

Hope this could help. Sandro

Web design is about designing

2008-06-23T20:01:00Z

It seems pretty obvious, but it isn’t. I assure you that.
I’ve just read Amy Hoy article “Design is not about solving problems” on Slash7 and I agree with her. She focused on the proactive role in designing, blaming the reactive role that design could have. Design is not about solving problems.

But I’d like to go further, remarking the obvious: design is about designing. Understanding the domain language (as recalled by Ryan Singer ), sketching the whole project down, positioning objects on a surface to fulfill the need and then build a mock-up. That is design. Web design makes no objections to this rule, but for sure it adds some constraints to the general process: the format. If a web designer builds up the complete idea of a project, without worrying about the final format of his work, he will probably have to plan a big rework. That project must be implemented by a software developer, so the format of the designer’s final object is fundamental.

Too often people speak different languages:

They simply don’t fit and sometimes tools don’t help a lot. This is why the big challenge is to forget about Photoshop and start promoting tools closer to the bare HTML.

HTML is composed by simple shapes. You can easily draw a rectangle, a square, color them, even blur the background. And again, set the font family, the boldness. Adding some AJAX you can get awesome effects… in a simple way. They are good and easily implemented, but you must study the fundamental of web development, the fundamental of browser rendering dialect.

People can keep basing their design work on tools like Photoshop, but they have to keep in mind that software developers will need user interface design objects in bare HTML/CSS format

If you are use to apply your work through a specific set of tools, it’s very difficult to change your habits in a short time. To train myself in this way I change the tools I use quite often, but of course I have my favorite tools too. At the moment I love using office tools like Keynote or PowerPoint to design web applications. They help you draw simple shapes and words quickly, and they avoid you to design hard things to implement.

In any case, independently from the tools I like to use, I’ve learned to sketch my ideas on paper first. That’s absolutely faster and cheaper than any software tool on earth.
I make a drawing and then I take a picture of it with my (i)phone to record it on WhoDoes. The drawing phase starts days later.

Streamlined 1.0 hacks: add help text to forms.

2008-06-20T13:09:00Z

I’ve created a small Streamlined hack that let you implement a :help option while defining ‘user columns’, here’s a sample:


                :title,                 {
                                          :human_name   => "Book title",
                                          :help         => "Please specify the title of the book you're reading." 
                                        }

and this is the result (for ‘edit’ and ‘new’ views):

Instructions:

Here you’ll find what to change in the plugin:


#  in /lib/streamlined/column/base.rb 

# around line 9
attr_accessor :human_name, :link_to, :popup, :parent_model, :wrapper, :additional_column_pairs,
                :additional_includes, :filter_column, :help

# around line 196
      x.td(:class => 'sl_edit_value') do
        x << render_td(view, item)
        if(!help.nil?)
          x.p{ x << help }
        end  
      end

Hope you’ll find useful.

Sandro

In/Out by 37signals

2008-06-13T08:24:00Z

In/Out is an internal application by 37signals first sited by Jason Fried 2 months ago. They implemented it to keep in touch with each other during the workday without useless interruptions:

In/Out is based on a simple need. People working together, on the same team or the same project, that sometimes need to know what each person is doing during the day.

What are you working on? When someone asks you this question it interrupts you and if 3, 4 or 5 people ask the same question during the day, it’s better that you take the day off.

In/Out helps to solve this problem efficiently. Each person in the team can use this tool to notify their actual status to others, and at the same time they can add log entries just describing what they have just accomplished.

The main page – and I suppose the only one – of this application allows you to see on the left side what has been finished by everyone during the day, while on the right side every worker can see each others status and the list of what they’ve already finished:

It’s probably one of the most innovative and simple tools that I’ve ever seen.

There’s only one thing that I cannot understand. Why they don’t release it as a stand alone product? I think it could be a major hit. Of course making something similar is not hard for anyone – so it cannot be considered a real asset for 37signals. Actually they only released it as part of Backpack.

But having conceived something so simple and at the same time so useful is really impressive. It’s like having designed the first non-Twitter application for the business, using the same fundamental principle of “simply useful” – I’ll get back on this concept again in future articles.

There’s only a subtle doubt I have. What if they decided not to release it stand alone to avoid cannibalizing their golden egg, Basecamp?
Mmmmhhhh…

If I was Jason Fried I would be studying a smart way to release it as a stand alone application and at the same time, have it integrated as a “module” of Basecamp – like they have already done with Writeboard.

For those of you that want to have some details there’s a short video describing this application at work – now renamed as Backpack Journal:

References:
- A peek at In/Out an internal app at 37signals
- Launch: the Backpack Journal

A free book about Rails 2.1

2008-06-11T12:53:00Z

“A gift from all Brazilian Railers to the international community”.

This is how Carlos Brando presented the release of a free book about Ruby on Rails 2.1 that he and Marcos Tapajós just released on the Internet.

The book has been translated from Portuguese thanks to the aim of the Brazilian Rails community in general, and in particular with the effort of Rafael Barbosa, Caike Souza, Pedro Pimentel, Abraão Coelho and Ricardo S Yasuda.

Thanks guys.

Is DHH planning to step back?

2008-06-10T23:21:00Z

I’ve been to Portland to the RailsConf 2008 and everything has been quite great. Great venue, a lot of people and good food too – and that was really a surprise :)

There’s only one thing that left me a bit confused: “David Heinemeier Hansson”. I mean, he’s a great speaker and hacker too, but this year he didn’t make any technical speeches at the conference. He left that role to Jeremy Kemper, who is for sure a wizard inside the Ruby on Rails community, but… he’s not David of course.

David has a unique role in the Rails community, and right now the Rails future and success is definitely tied to him. The community needs a leader and a mentor, and David is the man.

But what will happen if he stops having a technical leading role in Ruby on Rails?
That could really be a bad strike for all of us. The framework is too young and it’s still gaining a dominant position in the technology landscape. It needs its creator more than ever.

A second “bad” sign I picked up on was during the final speech, with all the Rails core team on stage, David did not seem to be completely up-to-date with the actual status of Rails – and Michael Koziarski had to correct him once.

That was not a good thing. Definitely not a good thing.
In the end, just to give us the final shot, he decided that “it could be a good idea” to leave the conference 15 minutes earlier to catch the flight :)

What’s up man?
Does it mean something is changing?
Is he planning to step back from his role?
I hope not, because in that case Ruby on Rails could be threatened very quickly by its competitors, risking to lose its rising star role in the technology landscape.

So David, please stop evangelizing and show us the light. We need you to make some code.

Spread out the good novel

2008-06-09T20:23:00Z

RailsConf is over and I was so lucky to be there this year too. GotThingsDone.com presence at the all-important convention about Ruby on Rails has been centered around spreading the good novel” out all over the world. Let me explain you why.

We were pretty impressed last year discovering that quite a few people were covering the event professionally with videos, interviews and keynotes streaming. The most part of the attendees having a blog were summarizing the convention in real time on their web sites and they did a good job, but I soon realized people want to see their heroes, want to hear their voices. Dancan made amazing pictures and he shared them on Flickr, but you know, they cannot speak.

So, this year we decided that Rails is too important to not have any good video interview to show the people who were not as lucky as we were. We wanted to show what a revolution was taking place in Portland.

So, in the last few days preceding the conference the crew at GotThingsDone.com and I planned to interview some of the people we thought are leading the Rails scenario right now. We aren’t professional in producing videos, but we made our best to share the intense moments we had there.

So I’d like to say thank you to the people we interviewed, because they were so patient and kind with us. Thanks to David Heinemeier Hansson, Joel Splosky, Jeremy Kemper, Ola Bini, John Straw, Ryan Singer, Rick Olson, Chris Wanstrath and Geoffrey Grosenbach.

And then thank you to Annalisa, Sandro and Joe for their wonderful job.

At Portland we were about 1,800 people. Right now our interviews have been viewed more than 7,300 times :)

RailsConf 2008 Keynotes now available...

2008-06-09T07:18:00Z

David Heinemeier Hansson, Jeremy Kemper, Kent Beck and Joel Spolsky.

If you missed out on the RailsConf 2008 this year or you would just like to have a recap on the Keynotes, you can now view them here.

If you have not yet seen the interviews of DHH, Jeremy Kemper and many more…. please view them here.

Annalisa

Now available: Interviews for your iPhone/iPod

2008-06-05T15:41:00Z

As we promised here are the links to download the interviews and view them on your iPhone or your iPod.

David Heinemeier Hannson
Ryan Singer
Jeremy Kemper
Rick Olsen
Ola Bini
Geoffrey Grosenbach
Chris Wanstrath
Joel Spolsky
John Straw

Interviews soon available on iPhone/iPhod...

2008-06-05T13:44:00Z

Stay tuned, we are currently working on the interviews to make them available for you in iPhone and iPod format.

They will be published in the next few hours….

Adam Pisoni: Skynet - A Ruby Map/Reduce Framework

2008-06-05T08:14:00Z

Pisoni illustrates Skynet, a Ruby framework to develop applications with regards to the Map/Reduce model.

Map/Reduce is a programming model aimed at the developing of distributed applications that automatically manage the major parts of the problems of distributing computing; map/reduce enables you to create parallel applications.

Skynet is a framework for the distributed computing on Ruby (like MapReduce) with some differences: Map/Reduce uses two types of processes, masters and workers. Skynet only has workers (the role of of the master is that to assign activities divided into tasks.

But without masters how can we divide the work into tasks? Each worker becomes a master for a particular job, and takes on the responsibility to divide the work into tasks and assign them.

Each worker observes the others in a way to understand if a task fails. When a task is taken up, it is automatically “copied” in the future, if the worker finishes the task it also cancels the future copied task otherwise it is left for someone else to pick it up.

How does Skynet follow your code?


mapreduce (users) do |u|
      codice
end

To use Skynet you need to use the following command:


skynet_start

(note: you need to restart skynet each time you change the code)

Skynet & Rails

Skynet can be used in conjunction with Rails for the following tasks:

send an e-mail
to execute a migration

Annalisa

Lightening Tasks

2008-06-04T15:56:00Z

With Lightning Tasks it intends all the presentations that are non foreseen in the program to those that are granted a very limited space (10 minutes). Some followed projects/interesting ideas come out during these micro sessions:

Saturday 31 May 2008

Between the most interesting sessions in this day RAD is surely mentioned, a framework that allows you to use Ruby to Arduino

The guys from FozWorks have presented and preview of a patch for Sphinx that makes it possible to search based on the geographical distance between the two or more objects.

In conclusion it was very appreciated also the intervention of Josh Goebel the creator of the famous Pastie that entertained the audience speaking about the advanced functionality of the application, like integrating with textmate, vim and the Pastie bot for IRC.

Sunday 1 June 2008

From the proposals of the sessions of Sunday, the following must be mentioned:

MethodTrails

It is an application for Ruby 1.9, visualized and printed in a graph all the internal relationships of a Rails application (the relations between the various methods).

Plugin: RESTFUL workflow A plugin to create a workflow similar to that of an interview that allows you to create a wizard of n-pages with saving the data at the end. The workflow is defined from a DSL.

Dave Woodward

He presented a REST interface through that a Rails application can have a dialogue with Jabber.

Last but not least, an expected RSpec Story Runner bundle with Textmate was presented (personally).

Annalisa

Obie Fernandez: Ruby coding best practices

2008-06-04T14:44:00Z

Through examples e fragments of code Obie show the practices to avoid when developing in Rails.

Obie: You need to know the basis of ruby before you can declare yourself a Rails developer. David Black has published a book for those who would like to learn ruby knowing only Rails.

Those who do not know Ruby can construct a very complicated construction when you could use ‘shortcut’ offered by Ruby; we don’t reinvent things that Ruby has already created and optimized. (for example there exists a function include? to control if an element is in an array without creating a cycle).

It is important to use the routes and the dynamic associations

On the screen appeared a method that before carries out a query on all the photos to choose a random id and retrieve with another query that photo, clearly not a good programming example.

At times the laziness easily takes the programmer to make various errors.

It is important to use various methods that follow simple actions, not to create methods that make many diverse things!

The speaker in front now ironically defines some errors “Premature DeOptimization” that are centered on generating code that decreases the execution of the application, also to generate actions directly in the ApplicationController is not a good idea.

Abuse of the database, happens when we use without too much reflection the functionality of ActiveRecord (like for example we use with light association dynamically inside the cycle).

Also to use the cache in a way that is wrong and dangerous. You don’t cache anymore putting the data inside the global constants/variables in how much it finishes all the RAM.

Don’t create controllers that are too long.

On the screen appeared a long action (about a hundred lines) that at the end of the process has ‘return true’, applauding and laughs came from the room. It is important that you encapsulate all the logic of the business in the models following the thin controller principle, fat models.

We must also be careful to maintain the code created always readable, not to be tempted to “compress” the code too much.

The RESTful architecture must be used correctly (on the screen compiles a controller attached to a shopping site with various procedures, that are for nothing RESTful)

We need to always try to use diverse plugins that make the same thing to understand which is the most functional and performance the best.

When the HTML helper degenerates: on the screen appeared a helper to generate a frame and inside a photo, the helper is hundreds of rows long and the speaker shows how difficult it is to maintain a function of this type. In this case what does it verify, says the speaker, it is good to know that it is needed to generate a new level of extraction to manage the problem (for example to create a ad-hoc model).

We create a methods with constant names, that are most possibly self explanatory (on the screen appears a method that is called finderer that returns a set of options for a method find, difficult to extrapolate without reading the comments).

We cancel the commented code, in any case we use SVN or GIT that keeps track of these things….

On the screen appears the UsersController, an complete application all in a controller, the curse of best practice, applauding and laughs came from the audience.

Conclusions

learn the fundamentals (of Ruby, of Rails) Rails is not a magic language that makes programmers those who don’t know, it is faster to establish on the conventions but it is necessary to know how to use them!
learn to learn from people that know more than us, if it is maybe possible to program together with people (pair programming). (the best would, says Obie would be to take SmallTalk programmers with years of experience)
Read books about the subject.

Annalisa