Class: Canis::ButtonGroup

Inherits:
Object show all
Defined in:
lib/canis/core/widgets/rwidget.rb

Overview

This is not a visual class or a widget. This class allows us to attach several RadioButtons to it, so it can maintain which one is the selected one. It also allows for assigning of commands to be executed whenever a button is pressed, akin to binding to the fire of the button, except that one would not have to bind to each button, but only once here.

Added on 2014-04-30

Examples:

group = ButtonGroup.new
group.add(r1).add(r2).add(r3)
# change the color of +somelabel+ to the color specified by the value of clicked radio.
group.command(somelabel) do |grp, label| label.color(grp.value); end

Since:

  • 1.2.0

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize ⇒ ButtonGroup

Returns a new instance of ButtonGroup.

Since:

  • 1.2.0



3497
3498
3499
3500
 
# File 'lib/canis/core/widgets/rwidget.rb', line 3497

def initialize 
  @elements = []
  @hash = {}
end

Instance Attribute Details

#elements ⇒ Object (readonly)

Array of buttons that have been added.

Since:

  • 1.2.0



3493
3494
3495
 
# File 'lib/canis/core/widgets/rwidget.rb', line 3493

def elements
  @elements
end

#value ⇒ Object (readonly)

the value of the radio button that is selected. To get the button itself, use selection.

Since:

  • 1.2.0



3496
3497
3498
 
# File 'lib/canis/core/widgets/rwidget.rb', line 3496

def value
  @value
end

Instance Method Details

#add(e) ⇒ Object

Since:

  • 1.2.0



3502
3503
3504
3505
3506
3507
 
# File 'lib/canis/core/widgets/rwidget.rb', line 3502

def add e
  @elements << e
  @hash[e.value] = e
  e.variable(self)
  self
end

#command(*args, &block) ⇒ Object

install trigger to call whenever a value is updated

Since:

  • 1.2.0



3530
3531
3532
3533
3534
3535
 
# File 'lib/canis/core/widgets/rwidget.rb', line 3530

def command *args, &block
  @commands ||= []
  @args ||= []
  @commands << block
  @args << args
end

#get_value(name = nil) ⇒ Object

returns the value of the selected button NOTE: This is used by RadioButton class for backward compat with Variable. User programs should use value()

Since:

  • 1.2.0



3563
3564
3565
 
# File 'lib/canis/core/widgets/rwidget.rb', line 3563

def get_value name=nil
  @value
end

#remove(e) ⇒ Object

Since:

  • 1.2.0



3508
3509
3510
3511
3512
 
# File 'lib/canis/core/widgets/rwidget.rb', line 3508

def remove e
  @elements.delete e
  @hash.delete e.value
  self
end

#select(button) ⇒ Object

select the given button or value. This may be called by user programs to programmatically select a button

Since:

  • 1.2.0



3538
3539
3540
3541
3542
3543
3544
3545
 
# File 'lib/canis/core/widgets/rwidget.rb', line 3538

def select button
  if button.is_a? String
    ;
  else
    button = button.value
  end
  set_value button
end

#selected?(val) ⇒ true or false

Returns for wether the given value or button is the selected one.

Parameters:

  • +value+ (String, RadioButton) —

    of a button, or Button itself to check if selected.

Returns:

  • (true or false) —

    for wether the given value or button is the selected one

Since:

  • 1.2.0



3521
3522
3523
3524
3525
3526
3527
 
# File 'lib/canis/core/widgets/rwidget.rb', line 3521

def selected? val
  if val.is_a? String
    @value == val
  else
    @hash[@value] == val
  end
end

#selection ⇒ Object

Returns the radiobutton that is selected.

Returns:

  • the radiobutton that is selected

Since:

  • 1.2.0



3515
3516
3517
 
# File 'lib/canis/core/widgets/rwidget.rb', line 3515

def selection
  @hash[@value]
end

#set_value(value, name = nil) ⇒ Object

when a radio button is pressed, it calls set_value giving the value of that radio. it also gives the name (optionally) since Variables can also be passed and be used across groups. Here, since a button group is only for one group, so we discard name. This is used by RadioButton class for backward compat with Variable.

Parameters:

  • value (String) —

    (text) of radio button that is selected

Since:

  • 1.2.0



3553
3554
3555
3556
3557
3558
3559
 
# File 'lib/canis/core/widgets/rwidget.rb', line 3553

def set_value value, name=nil
  @value = value
  return unless @commands
  @commands.each_with_index do |comm, ix|
    comm.call(self, *@args[ix]) unless comm.nil?
  end
end