class BBS::Widgets::ListBox

A scrolling list of items with one selected.

Attributes

items [RW]

items: the Array of items shown
selected: index of the selected item
scroll: index of the item on the top row
on_select: callable invoked as call(item, listbox) when the selection moves to another item
on_activate: callable invoked as call(item, listbox) on Enter; its result is returned from handle_event
label: callable turning an item into its display text; nil uses the item’s to_s

label [RW]

items: the Array of items shown
selected: index of the selected item
scroll: index of the item on the top row
on_select: callable invoked as call(item, listbox) when the selection moves to another item
on_activate: callable invoked as call(item, listbox) on Enter; its result is returned from handle_event
label: callable turning an item into its display text; nil uses the item’s to_s

on_activate [RW]

items: the Array of items shown
selected: index of the selected item
scroll: index of the item on the top row
on_select: callable invoked as call(item, listbox) when the selection moves to another item
on_activate: callable invoked as call(item, listbox) on Enter; its result is returned from handle_event
label: callable turning an item into its display text; nil uses the item’s to_s

on_select [RW]

items: the Array of items shown
selected: index of the selected item
scroll: index of the item on the top row
on_select: callable invoked as call(item, listbox) when the selection moves to another item
on_activate: callable invoked as call(item, listbox) on Enter; its result is returned from handle_event
label: callable turning an item into its display text; nil uses the item’s to_s

scroll [RW]

items: the Array of items shown
selected: index of the selected item
scroll: index of the item on the top row
on_select: callable invoked as call(item, listbox) when the selection moves to another item
on_activate: callable invoked as call(item, listbox) on Enter; its result is returned from handle_event
label: callable turning an item into its display text; nil uses the item’s to_s

selected [RW]

items: the Array of items shown
selected: index of the selected item
scroll: index of the item on the top row
on_select: callable invoked as call(item, listbox) when the selection moves to another item
on_activate: callable invoked as call(item, listbox) on Enter; its result is returned from handle_event
label: callable turning an item into its display text; nil uses the item’s to_s

Public Class Methods

new (items: [], on_select: nil, on_activate: nil, label: nil, **kw)

Source

# File lib/bbs/widgets/list_box.rb, line 21
def initialize(items: [], on_select: nil, on_activate: nil, label: nil, **kw)
  super(**kw)
  @items       = items
  @selected    = 0
  @scroll      = 0
  @on_select   = on_select
  @on_activate = on_activate
  @label       = label
end

Creates a list of items with the first one selected.

Calls superclass method BBS::Widget::new

Public Instance Methods

focusable? ()

Source

# File lib/bbs/widgets/list_box.rb, line 32
def focusable? = true

True: a list takes the focus.

handle_event (event)

Source

# File lib/bbs/widgets/list_box.rb, line 49
def handle_event(event)
  return nil unless enabled
  return key(event.key) if event.key?
  return click(event.y - bounds.y) if Widgets.click_in?(event, bounds)

  rows = Widgets.wheel(event, bounds)
  rows && select_index(@selected + rows)
end

Moves the selection with Up, Down, Page Up, Page Down, Home and End (calling on_select when it changes), calls on_activate on Enter, selects the clicked item on a left click and scrolls the selection by three on the mouse wheel. Returns :handled (or on_activate‘s result on Enter), and nil for other events or when disabled.

render (frame)

Source

# File lib/bbs/widgets/list_box.rb, line 38
def render(frame)
  return if no_room?

  bounds.height.times { |r| draw_row(frame, r) }
end

Draws the visible items into the bounds of frame, the selected one highlighted (more strongly when the list has the focus).

selected_item ()

Source

# File lib/bbs/widgets/list_box.rb, line 34
def selected_item = @items[@selected]

The selected item, or nil when the list is empty.