module BBS::Dialogs

Ready-made modal dialogs for a BBS::Application: a message, a yes/no confirmation, and a one-line input. Each opens a centred Window on app and returns it; the buttons close it.

BBS::Dialogs.confirm(app, 'Delete this post?', on_yes: -> { delete(post) })

Constants

BUTTON_ROW: The button row, counted up from the bottom edge.
BUTTON_WIDTH: Width of an OK, Yes or No button.
CANCEL_WIDTH: Width of the Cancel button.
CHROME_ROWS: Rows of a message or confirm box beside its text lines: the borders, the blank lines and the button row.
CONFIRM_MIN_WIDTH: The narrowest confirm box.
HALF_GAP: Columns between the middle of the window and each of two buttons side by side.
INPUT_HEIGHT: The height of an input box.
INPUT_ROW: The window row of the text field of an input box.
INPUT_WIDTH: The default width of an input box.
MESSAGE_MIN_WIDTH: The narrowest message box.
PADDING: Columns between the window’s left edge and its text, and between the text and the right edge.
SCREEN_MARGIN: Cells kept free between a dialog and each screen edge.
TEXT_CHROME: Columns of a message or confirm box beside its wrapped text.
TEXT_TOP: The window row of the first text line, below the top border.
WRAP_WIDTH: The width a message without a fixed width and a confirm text are wrapped at.

Public Class Methods

centred_window (app, width:, height:, title: nil)

Source

# File lib/bbs/dialogs.rb, line 52
def self.centred_window(app, width:, height:, title: nil)
  cols  = app.cols
  rows  = app.rows
  w     = [width, cols - (2 * SCREEN_MARGIN)].min
  h     = [height, rows - (2 * SCREEN_MARGIN)].min
  x     = ((cols - w) / 2) + 1
  y     = ((rows - h) / 2) + 1
  win   = Window.new(title: title, modal: true)
  win.layout(x, y, w, h)
  win
end

Builds a modal Window of width x height cells centred on app‘s screen, shrunk to leave a two-cell margin. The window is not opened.

Returns the Window.

confirm (app, text, title: ' Confirm ', on_yes: nil, on_no: nil)

Source

# File lib/bbs/dialogs.rb, line 80
def self.confirm(app, text, title: ' Confirm ', on_yes: nil, on_no: nil)
  lines  = wrap(text, WRAP_WIDTH)
  window = text_box(app, lines, fit(lines, CONFIRM_MIN_WIDTH), title)
  pair(window, Widgets::Button.new(label: '&Yes', on_click: closer(app, window) { on_yes&.call }),
       Widgets::Button.new(label: '&No', on_click: closer(app, window) { on_no&.call }), BUTTON_WIDTH)
  show(app, window)
end

Opens a Yes/No box with text. Each button closes the box, then calls on_yes or on_no when given.

Returns the Window.

input (app, prompt:, title: ' Input ', value: '', width: INPUT_WIDTH, on_submit: nil)

Source

# File lib/bbs/dialogs.rb, line 94
def self.input(app, prompt:, title: ' Input ', value: '', width: INPUT_WIDTH, on_submit: nil)
  window = centred_window(app, width: width, height: INPUT_HEIGHT, title: title)
  inner  = window.bounds.width - (2 * PADDING)
  place(window, Widgets::Label.new(text: prompt, style_key: :window_text), PADDING, TEXT_TOP, inner)
  field = Widgets::TextInput.new(value: value)
  field.on_submit = closer(app, window) { on_submit&.call(field.value) }
  place(window, field, PADDING, INPUT_ROW, inner)
  pair(window, Widgets::Button.new(label: '&OK', on_click: field.on_submit),
       Widgets::Button.new(label: '&Cancel', on_click: closer(app, window)), CANCEL_WIDTH)
  show(app, window, focus: field)
end

Opens a box with prompt, a text field holding value, and OK and Cancel buttons. OK, or Enter in the field, closes the box and calls on_submit with the entered text; Cancel only closes it. The field has the focus.

Returns the Window.

message (app, text, title: ' Message ', width: nil)

Source

# File lib/bbs/dialogs.rb, line 68
def self.message(app, text, title: ' Message ', width: nil)
  lines  = wrap(text, width ? width - TEXT_CHROME : WRAP_WIDTH)
  window = text_box(app, lines, width || fit(lines, MESSAGE_MIN_WIDTH), title)
  ok     = Widgets::Button.new(label: '&OK', on_click: closer(app, window))
  place(window, ok, (window.bounds.width - BUTTON_WIDTH) / 2, button_row(window), BUTTON_WIDTH)
  show(app, window)
end

Opens a message box with text, word-wrapped, and an OK button that closes it. width fixes the box width; by default it fits the text.

Returns the Window.