RoR implementation of dhtmlx Gantt chart

The Dhtmlxagantt is an application which implements dhtmlx Gantt chart in Rails framework as simple as possible. This document contains implementation notes and gotcha's.

You can read about Gantt chart here.

You can read about dhtmlx and their awsome interactive JavaScript Gantt chart here.

Components

• Rails version 4.1

• GUI component dhtmlx gantt version 3.1 (standard version)

• Ruby version 2.1

Limiting dhtmlx default widget configuration

Default Gantt chart component functionality is shrinked here as follows:

1. You can overview just one project on the chart.

2. You can add task (using plus icon) to the project but you can not add task to the task (subtask). If you want to omit these limitation and keep standard edition then simply take out the following code.

   <style>
     [task_id^='task-'] .gantt_add, .gantt_grid_head_add {
       display: none !important;
     }
   </style>

   from your index.html.erb file.

3. You can add only tasks but not a project because functionality of milestones, projects and adding custom types has been moved to PRO version (commercial or enterprise editions).

Extending dhtmlx default widget

I have add the following extansions to default library:

1. Full screen mode feature (dhtmlxgantt_expand.js).

2. Store manual order of tasks feature.

Asset pipeline

No CSS or JS files will be available to your app through the asset pipeline unless they are listed in the config.precompile directive

Rails.application.config.assets.precompile += %w( 
  dhtmlxgantt.css 
  skins/dhtmlxgantt_skyblue.css
  dhtmlxgantt.js 
  locale/locale.js 
  ext/dhtmlxgantt_marker.js 
  ext/dhtmlxgantt_quick_info.js
  ext/dhtmlxgantt_tooltip.js
  ext/dhtmlxgantt_expand.js
)

in your config/initializers/assets.rb file.

Usage notes

1. This example is developed to easily adapt to your own application.

2. Project is kind of scope for Tasks and Links thus if you delete a project then all its links and tasks will be deleted too.

3. Gantt charts illustrate the start and finish dates of the terminal elements and summary elements of a project thus if your task has not start_date nor duration then it will not show up.

4. Associations between links, tasks and project are polymorphic. So, you can easy expand the app to milestones, phases or any other custom object you like.

5. In you want to silance "WARNING: Can't verify CSRF token authenticity" for json requests then you have to write in your application_controller.rb file:

protect_from_forgery with: :null_session, if: Proc.new { |c| c.request.format == 'application/json' }

Demo

There are some task examples in db/seeds.rb file. So, you might begin with run rake db:setup

and your demo chart should look like this