vinstall Package

vinstall Package

Vinstall

Introduction

Vinstall is a Python framework for an installer application for GNU/Linux operating systems, specially VectorLinux and Vlocity Linux.

User guide

The Controller and Application objects

The installer is like a wizard application. It will present to the user a set of pages or screens, containing some options used for controlling the process. Each page of the installer is represented by a Controller class. The controller class as a unit, will define what to show to the user, how to react to the user input, and what are the next and previous stages of the application. So what we are actually going to do, is to write one controller class for each page, and then we will create an Application object, which will direct the whole process for us.

The Controller interface

There is an Interface (a set of methods) that any controller class needs to implement:

render():

The render method needs to return a Render object. Here you will setup your options, the title and introductory text for the screen. The Render object will be explained later.

process(*args):

This method will be used to process the user input after she activates the “next” button. Use this for actually doing something. It will be called using the values from the user as arguments.

next():

Return the next controller class or ´´None´´. ´´None´´ indicates the end of the application.

previous():

Return the previous controller class or ´´None´´. The first controller class would tipically return ´´None´´. Use this method for performing any clean up if necessary.

After defining one controller class for each page, we need an Application object, which takes the name of the view as first argument and the first controller class as second argument. Use the run method of the Application instance for starting the application. The Application object will instantiate the first controller and present it to the user, after that it will direct the whole process for you.

The Render object

The Render object is in charge of taking the options,find a view or rendering class for each them, and then will return them to the application object for presenting them to the user. The only thing you need to know about it is how to create and instance:

Render(<title>, <intro>, <*options>)

It is very simple, the first two arguments are strings, and the following arguments must be instances of any class from the core.model module. you can pass as amny options as you need.

The model module

The model module contains classes representing options in an abstract way. Tipically, the constructor for any model class will take a string as first argument which will be used to create a caption or label for the option. The rest of the arguments should be optional,and may vary. NumericOption can take a minvalue or a maxvalue argument, and so on. A help keyword argument is accepted in every class, and should be rendered later as a tooltip or help text, depending on which UI toolkit is used. Check out the vinstall.core.model module for more information, keep in mind that this one is likely to change during the installer development. Todo: add details for each model class and its constructors.

Framework development guide

This section will document stuff like how to add a new View, how to create model classes, how to extend the code, etc. Todo

example Module

Example application

class vinstall.example.State

Bases: vinstall.core.controller.Controller

Welcome screen

command(*args)

next()

previous()

process(*args)

render()

class vinstall.example.State1

Bases: vinstall.core.controller.Controller

The first stage of the application.

command(*results)

init()

next()

Return the next stage of the application.

previous()

Return the previous state of the application, if it is None, the application will just quit.

process(result, result_ddown)

Do something with the user input. The arguments passed to this method will be equal to the number of models passed to the Render object in the render method.

render()

Create a render object.

class vinstall.example.State2

Bases: vinstall.core.controller.Controller

The second page of our application. The render method needs to return a Render object. This render object will pass the abstract form elements to the proper view. The first argument is the title of the page, the second is the intro text, and finally, you pass all your options, for example:

def render(self):

return (“Title”, “Intro”, opt1, opt2, opt3)

Where opt* are instances of any class from the core.model module.

command(*result)

Command 10

next()

The next state, None for quiting.

previous()

The previous state, if you need to do any clean up, do it here.

process(result, result1)

Process user input

render()

Create a Render object with our options. You can append as many options as you want. the first argument to the render object is the window title, then the introductory text, and then the form elements. The model objects usually take the captio or label as first arg.

Subpackages

• backend Package
  • keyboard Module
  • media Module
  • utils Module
• core Package
  • core Package
  • application Module
  • command Module
  • controller Module
  • core Module
  • log Module
  • model Module
  • observer Module
  • render Module
  • view Module
• ui Package
  • gtk Module
  • urwid Module