class BBS::Widgets::Button

A push button. Label syntax: “Save” or “&Save” (the ampersand marks the hotkey letter). Pressing Alt+letter, or Enter, Space or a click while focused, fires on_click.

Attributes

label [RW]

label: the button text; an & marks the hotkey letter
on_click: callable invoked as call(button) when the button fires; returning :halt ends the application

on_click [RW]

label: the button text; an & marks the hotkey letter
on_click: callable invoked as call(button) when the button fires; returning :halt ends the application

Public Class Methods

new (label: 'OK', on_click: nil, **kw)

Source

# File lib/bbs/widgets/button.rb, line 17
def initialize(label: 'OK', on_click: nil, **kw)
  super(**kw)
  @label    = label
  @on_click = on_click
end

Creates a button with label (default 'OK') and on_click.

Calls superclass method BBS::Widget::new

Public Instance Methods

display_label ()

Source

# File lib/bbs/widgets/button.rb, line 31
def display_label = Hotkey.plain(@label)

The label without its & marker.

fire ()

Source

# File lib/bbs/widgets/button.rb, line 47
def fire
  return :handled unless enabled

  @on_click&.call(self) == :halt ? :halt : :handled
end

Calls on_click with the button, unless the button is disabled. Returns :halt when on_click returned :halt, :handled otherwise.

focusable? ()

Source

# File lib/bbs/widgets/button.rb, line 24
def focusable? = true

True: a button takes the focus.

handle_event (event)

Source

# File lib/bbs/widgets/button.rb, line 56
def handle_event(event)
  return nil unless enabled
  return fire if event.key? && [:enter, ' '].include?(event.key)

  Widgets.click_in?(event, bounds) ? fire : nil
end

Fires the button on Enter, Space, or a left click inside its bounds; returns the result of fire. Returns nil for other events and when disabled.

hotkey ()

Source

# File lib/bbs/widgets/button.rb, line 28
def hotkey = Hotkey.letter(@label)

The hotkey letter after the & in the label, downcased, or nil when the label has none.

render (frame)

Source

# File lib/bbs/widgets/button.rb, line 36
def render(frame)
  return if bounds.width <= 0

  blank(frame, 0, sgr)
  text = "[ #{display_label} ]"[0, bounds.width]
  col  = [(bounds.width - text.length) / 2, 0].max
  hotkey_parts && enabled ? put_with_hotkey(frame, col) : put(frame, col, 0, text, sgr)
end

Draws the button as [ label ] centred on the first row of the bounds into frame, in the focused, normal or disabled button style, with the hotkey letter highlighted.