Vedeu

Vedeu is my attempt at creating a terminal based application framework without the need for Ncurses. I've tried to make Vedeu as simple and flexible as possible.

Installation

Add this line to your application's Gemfile:

gem 'vedeu'

And then execute:

$ bundle

Example

Have a look at: https://github.com/gavinlaking/playa

Usage

Expect proper documentation soon!

Getting Started

require 'vedeu'

class MyApp
  include Vedeu

  interface 'main' do
    ...
  end

  event :some_event do
    # ...
  end

  event :other_event do |hash_args, array_args, args|
    # ...
  end

  event :key do |key|
    case key
    when 'a' then puts "Apple"
    when 'b' then puts "Banana"
    # ...
    when :f1 then trigger(:some_event)
    when :f2 then
      trigger(:other_event, { args: here }, [:or, :here], :etc)
    end
  end
end

Building Views

Views with Vedeu are made up of simple building blocks. These blocks can be arranged in a multitude of ways which I hope is more than sufficient for your design needs.

Interfaces (Interface) are made up of lines. (Line)
Lines are made up of zero, one or multiple streams. (Stream)
An interface, line or stream can have a colour (colour) attribute.
An interface, line or stream can have a style (style) attribute.
Interfaces have a position (y, x) on the screen, and a size. (width, height)
Interfaces can be placed relative to each other based on their attributes. (top, right, bottom, left)
Colours are defined in CSS-style values, i.e. #ff0000 would be red.
Styles are named. See the table below for supported styles.

Some Terms

To understand how Vedeu works, you need to familiarise yourself with some terms.

Interface: This is an area on the screen where you can take input or direct output. You will define it's colour and style, its dimensions, including position and give it a name. You can then direct the output of a command to this interface and Vedeu will ensure the content is placed there.
Line: An interface is composed of many lines. Their length being the width of the interface and their number being the height of the interface.

An interface with width: 12, height: 5 will have five lines, each made of 12 characters.

Stream: A stream is a subset of a line. Having streams basically allow us to apply styles and colours to part of a line; their not necessary, but provide you with greater flexibility for your output.

On Defining Interfaces

interface 'main' do
  y      1
  x      1
  width  10 # see notes below
  height 10
  colour foreground: '#ffffff', background: '#000000'
  cursor false
end

Referring to the above example, interfaces have a name, and various default attributes.

y sets the starting row point. (See Geometry)
x sets the starting column point.
width sets character width of the interface
height sets character height of the interface

Note: not setting a width or height will set the values to the terminal's reported width and height.

foreground sets the default foreground colour. (See Colours)
background sets the default background colour.
cursor is a Boolean specifying whether the cursor should show.

On Defining Events

event :event_name do |arg1, arg2|
end

One can define events which perform work or trigger other events. Vedeu has built-in events which are namespaced with underscores:

:_initialize_ Special event which Vedeu triggers when it is ready to enter the main loop. Client applications can listen for this event and perform some action(s), like render the first screen, interface or make a sound.
:_clear_ Clears the whole terminal space.
:_exit_ when triggered, Vedeu will attempt to exit.
:_keypress_ triggering this event will cause the triggering of the key event; which you should define to 'do things'. If the escape key is pressed, then key is triggered with the argument :escape, also an internal event _mode_switch_ is triggered.
:_mode_switch_ when triggered (after the user presses escape), Vedeu switches from a "raw mode" terminal to a "cooked mode" terminal. The idea here being that the raw mode is for single keypress actions, whilst cooked mode allows the user to enter more elaborate commands- such as commands with arguments.
:_refresh_ triggering this event will cause all interfaces to refresh.
:_refresh_group_(group_name)_ will refresh all interfaces belonging to this group. E.g. _refresh_group_home_ will refresh all interfaces with the group of home.
:_refresh_(interface_name)_ will refresh the interface with this name. E.g. _refresh_widget_ will refresh the interface widget.

Note: Overriding or adding additional events to the Vedeu event namespace may cause unpredictable results.

Geometry

Geometry for Vedeu, as the same for ANSI terminals, is set top-left, which is point 1, 1. Interfaces have internal geometry which is handled automatically. Unless you are doing something special, you will probably only set it on a per-interface basis.

Colours

Vedeu uses HTML/CSS style notation (i.e. '#aadd00'), they can be used at the stream level, the line level or for the whole interface.

"colour": { "foreground": "#ff0000", "background": "#ffffff" }

Styles

Vedeu has a range of symbol styles which are compatible with most terminals which are ANSI compatible.

"style": []

Like colours, they can be defined in either interfaces, for specific lines or within streams. Styles are applied as encountered.

Style name	Escape Sequence
bg_reset	`\e[48;2;49m`
blink	`\e[5m`
blink_off	`\e[25m`
bold	`\e[1m`
bold_off	`\e[21m`
clear	`\e[2J`
clear_line	`\e[38;2;39m\e[48;2;49m\e[2K`
colour_reset	`\e[38;2;39m\e[48;2;49m`
fg_reset	`\e[38;2;39m`
hide_cursor	`\e[?25l`
negative	`\e[7m`
positive	`\e[27m`
reset	`\e[0m`
normal	`\e[24m\e[21m\e[27m`
dim	`\e[2m`
show_cursor	`\e[?25h`
underline	`\e[4m`
underline_off	`\e[24m`

Contributing

Fork it ( http://github.com/gavinlaking/vedeu/fork )
Clone it
bundle
rake or bundle exec guard
Create your feature branch (git checkout -b my-new-feature)
Write some tests, write some code, have some fun
Commit your changes (git commit -am 'Add some feature')
Push to the branch (git push origin my-new-feature)
Create a new pull request