Class: RNDK::Scroll

Inherits:
Scroller show all
Defined in:
lib/rndk/scroll.rb

Overview

A scrolling items of text.

Keybindings

Left Arrow:: Shift the items left one column. Right Arrow:: Shift the items right one column. Up Arrow:: Select the previous item in the items. Down Arrow:: Select the next item in the items. Prev Page:: Scroll one page backward. Ctrl-B:: Scroll one page backward. Next Page:: Scroll one page forward. Ctrl-F:: Scroll one page forward. 1:: Move to the first element in the items. <:: Move to the first element in the items. g:: Move to the first element in the items. Home:: Move to the first element in the items.

:: Move to the last element in the items. G:: Move to the last element in the items. End:: Move to the last element in the items. $:: Shift the items to the far right. |:: Shift the items to the far left. Return:: Exit the widget and return the index of the selected item. Also set the widget exit_type to :NORMAL. Tab:: Exit the widget and return the index of the selected item. Also set the widget exit_type to :NORMAL. Escape:: Exit the widget and return -1. Also set the widget exit_type :ESCAPE_HIT. Ctrl-L:: Refreshes the screen.

Instance Attribute Summary collapse

Attributes inherited from Widget

#BXAttr, #HZChar, #LLChar, #LRChar, #ULChar, #URChar, #VTChar, #accepts_focus, #binding_list, #border_size, #box, #exit_type, #has_focus, #is_visible, #screen, #screen_index, #supported_signals, #widget_type

Instance Method Summary collapse

Methods inherited from Scroller

#get_current_item, #max_view_size, #scroll_begin, #scroll_down, #scroll_end, #scroll_left, #scroll_page_down, #scroll_page_up, #scroll_right, #scroll_up, #set_current_item, #set_position, #set_view_size

Methods inherited from Widget

#Screen_XPOS, #Screen_YPOS, #after_processing, #before_processing, #bind_key, #bind_signal, #bindable_widget, #clean_bindings, #clean_title, #draw_title, #get_box, #getch, #is_bound?, #refresh_data, #run_key_binding, #run_signal_binding, #save_data, #setBXattr, #setHZchar, #setLLchar, #setLRchar, #setULchar, #setURchar, #setVTchar, #set_box, #set_exit_type, #set_title, #unbind_key, #valid?, #valid_type?

Constructor Details

#initialize(screen, config = {}) ⇒ Scroll

Creates a Scroll Widget.

  • x is the x position - can be an integer or RNDK::LEFT, RNDK::RIGHT, RNDK::CENTER.
  • y is the y position - can be an integer or RNDK::TOP, RNDK::BOTTOM, RNDK::CENTER.
  • scroll_bar is where the scrollbar will be placed. It can be only RNDK::LEFT, RNDK::RIGHT or RNDK::NONE, for no scrollbar.
  • width/height are integers - if either are 0, Widget will be created with full width/height of the screen. If it's a negative value, will create with full width/height minus the value.
  • title can be more than one line - just split them with \ns.
  • items is an Array of Strings to be shown on the Widget.
  • numbers is a flag to turn on/off line numbering at the front of the items items.
  • highlight is the attribute/color of the currently selected item at the items.
  • box if the Widget is drawn with a box outside it.
  • shadow turns on/off the shadow around the Widget.


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# File 'lib/rndk/scroll.rb', line 62

def initialize(screen, config={})
  super()
  @widget_type = :scroll
  @supported_signals += [:before_input,
                         :after_input,
                         :after_scrolling]
  x          = 0
  y          = 0
  scroll_bar = RNDK::RIGHT
  width      = 0
  height     = 0
  title      = "scroll"
  items      = []
  numbers    = false
  highlight  = RNDK::Color[:reverse]
  box        = true
  shadow     = false

  config.each do |key, val|
    x         = val if key == :x
    y         = val if key == :y
    scroll_bar    = val if key == :scroll_bar
    width     = val if key == :width
    height    = val if key == :height
    title     = val if key == :title
    items     = val if key == :items
    numbers   = val if key == :numbers
    highlight = val if key == :highlight
    box       = val if key == :box
    shadow    = val if key == :shadow
  end

  parent_width  = Ncurses.getmaxx screen.window
  parent_height = Ncurses.getmaxy screen.window

  box_width  = width
  box_height = height

  xpos = x
  ypos = y

  scroll_adjust = 0

  self.set_box box

  # If the height is a negative value, the height will be ROWS-height,
  # otherwise the height will be the given height
  box_height = RNDK.set_widget_dimension(parent_height, height, 0)

  # If the width is a negative value, the width will be COLS-width,
  # otherwise the width will be the given width
  box_width = RNDK.set_widget_dimension(parent_width, width, 0)

  box_width = self.set_title(title, box_width)

  # Set the box height.
  if @title_lines > box_height
    box_height = @title_lines + [items.size, 8].min + 2 * @border_size
  end

  # Adjust the box width if there is a scroll bar
  if scroll_bar == RNDK::LEFT || scroll_bar == RNDK::RIGHT
    @scrollbar = true
    box_width += 1
  else
    @scrollbar = false
  end

  # Make sure we didn't extend beyond the dimensions of the window.
  @box_width = if box_width > parent_width
               then parent_width - scroll_adjust
               else box_width
               end
  @box_height = if box_height > parent_height
                then parent_height
                else box_height
                end

  self.set_view_size(items.size)

  # Rejustify the x and y positions if we need to.
  xtmp = [xpos]
  ytmp = [ypos]
  RNDK.alignxy(screen.window, xtmp, ytmp, @box_width, @box_height)
  xpos = xtmp[0]
  ypos = ytmp[0]

  # Make the scrolling window
  @win = Ncurses.newwin(@box_height, @box_width, ypos, xpos)

  # Is the scrolling window null?
  if @win.nil?
    return nil
  end

  # Turn the keypad on for the window
  Ncurses.keypad(@win, true)

  # Create the scrollbar window.
  if scroll_bar == RNDK::RIGHT
    @scrollbar_win = Ncurses.subwin(@win,
                                    self.max_view_size,
                                    1,
                                    self.Screen_YPOS(ypos),
                                    xpos + box_width - @border_size - 1)
  elsif scroll_bar == RNDK::LEFT
    @scrollbar_win = Ncurses.subwin(@win,
                                    self.max_view_size,
                                    1,
                                    self.Screen_YPOS(ypos),
                                    self.Screen_XPOS(xpos))
  else
    @scrollbar_win = nil
  end

  # create the items window
  @items_win = Ncurses.subwin(@win,
                             self.max_view_size,
                             box_width - (2 * @border_size) - scroll_adjust,
                             self.Screen_YPOS(ypos),
                             self.Screen_XPOS(xpos) + (if scroll_bar == RNDK::LEFT then 1 else 0 end))

  # Set the rest of the variables
  @screen = screen
  @parent = screen.window
  @shadow_win = nil
  @scrollbar_placement = scroll_bar
  @max_left_char = 0
  @left_char = 0
  @highlight = highlight
  # initExitType (scrollp);
  @accepts_focus = true
  @input_window = @win
  @shadow = shadow

  self.set_position(0);

  # Create the scrolling items item items and needed variables.
  return nil unless self.create_item_list(numbers, items)

  # Do we need to create a shadow?
  if shadow
    @shadow_win = Ncurses.newwin(@box_height,
                                 box_width,
                                 ypos + 1,
                                 xpos + 1)
  end

  # Standard keybindings (plus the Arrow Keys)
  self.bind_key('g') { self.scroll_begin }
  self.bind_key('1') { self.scroll_begin }
  self.bind_key('G') { self.scroll_end   }
  self.bind_key('<') { self.scroll_begin }
  self.bind_key('>') { self.scroll_end   }

  screen.register(:scroll, self);
  self
end

Instance Attribute Details

#current_item ⇒ Object (readonly)

Returns the value of attribute current_item.



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# File 'lib/rndk/scroll.rb', line 37

def current_item
  @current_item
end

#highlight ⇒ Object (readonly)

Returns the value of attribute highlight.



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# File 'lib/rndk/scroll.rb', line 37

def highlight
  @highlight
end

#item ⇒ Object (readonly)

Returns the value of attribute item.



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# File 'lib/rndk/scroll.rb', line 37

def item
  @item
end

Instance Method Details

#activate(actions = []) ⇒ Object

Activates the Widget, letting the user interact with it.

actions is an Array of characters. If it's non-null, will #inject each char on it into the Widget.



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# File 'lib/rndk/scroll.rb', line 231

def activate(actions=[])
  self.draw

  if actions.nil? || actions.size == 0
    loop do
      self.fix_cursor_position
      input = self.getch

      # Inject the character into the widget.
      ret = self.inject input

      return ret if @exit_type != :EARLY_EXIT
    end
  else
    # Inject each character one at a time.
    actions.each do |action|
      ret = self.inject action

      return ret if @exit_type != :EARLY_EXIT
    end
  end

  # Set the exit type for the widget and return
  self.set_exit_type(0)
  return nil
end

#destroy ⇒ Object

This function destroys



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# File 'lib/rndk/scroll.rb', line 386

def destroy
  self.clean_title

  # Clean up the windows.
  RNDK.window_delete(@scrollbar_win)
  RNDK.window_delete(@shadow_win)
  RNDK.window_delete(@items_win)
  RNDK.window_delete(@win)

  # Clean the key bindings.
  self.clean_bindings

  # Unregister this widget
  @screen.unregister self
end

#draw ⇒ Object

This function draws the scrolling items widget.



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# File 'lib/rndk/scroll.rb', line 365

def draw
  # Draw in the shadow if we need to.
  Draw.drawShadow(@shadow_win) unless @shadow_win.nil?

  self.draw_title @win

  # Draw in the scrolling items items.
  self.draw_items @box
end

#erase ⇒ Object

This function erases the scrolling items from the screen.



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# File 'lib/rndk/scroll.rb', line 403

def erase
  RNDK.window_erase(@win)
  RNDK.window_erase(@shadow_win)
end

#focus ⇒ Object

do this to update the view size, etc

self.set_position(@current_item)

end end



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# File 'lib/rndk/scroll.rb', line 516

def focus
  self.draw_current
  Ncurses.wrefresh @items_win
end

#get_highlight(highlight) ⇒ Object 



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# File 'lib/rndk/scroll.rb', line 445

def get_highlight(highlight)
  return @highlight
end

#get_items(items) ⇒ Object 



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# File 'lib/rndk/scroll.rb', line 432

def get_items(items)
  (0...@item.size).each do |x|
    items << RNDK.chtype2Char(@item[x])
  end

  @item.size
end

#inject(input) ⇒ Object

See Also:



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# File 'lib/rndk/scroll.rb', line 259

def inject input
  ret = nil
  complete = false

  self.set_exit_type 0

  # Draw the scrolling items
  self.draw_items @box

  # Calls a pre-process block if exists.
  # They can interrup input.
  continue = run_signal_binding(:before_input, input)

  if continue

    # Check for a predefined key binding.
    if self.is_bound? input
      self.run_key_binding input

    else
      case input

      when Ncurses::KEY_UP
        self.scroll_up
        run_signal_binding(:after_scrolling, @current_item)

      when Ncurses::KEY_DOWN
        self.scroll_down
        run_signal_binding(:after_scrolling, @current_item)

      when Ncurses::KEY_LEFT
        self.scroll_left
        run_signal_binding(:after_scrolling, @current_item)

      when Ncurses::KEY_RIGHT
        self.scroll_right
        run_signal_binding(:after_scrolling, @current_item)

      when Ncurses::KEY_PPAGE
        self.scroll_page_up
        run_signal_binding(:after_scrolling, @current_item)

      when Ncurses::KEY_NPAGE
        self.scroll_page_down
        run_signal_binding(:after_scrolling, @current_item)

      when Ncurses::KEY_HOME
        self.scroll_begin
        run_signal_binding(:after_scrolling, @current_item)

      when Ncurses::KEY_END
        self.scroll_end
        run_signal_binding(:after_scrolling, @current_item)

      when RNDK::BACKCHAR
        self.scroll_page_up
        run_signal_binding(:after_scrolling, @current_item)

      when RNDK::FORCHAR
        self.scroll_page_down
        run_signal_binding(:after_scrolling, @current_item)

      when '$' then @left_char = @max_left_char
      when '|' then @left_char = 0

      when RNDK::KEY_ESC
        self.set_exit_type(input)
        complete = true

      when Ncurses::ERR
        self.set_exit_type(input)
        complete = true

      when RNDK::REFRESH
        @screen.erase
        @screen.refresh

      when RNDK::KEY_TAB, Ncurses::KEY_ENTER, RNDK::KEY_RETURN
        self.set_exit_type(input)
        ret = @current_item
        complete = true
      end
    end

    run_signal_binding(:after_input, input) if not complete
  end

  if not complete
    self.draw_items @box
    self.set_exit_type(0)
  end

  self.fix_cursor_position
  @result_data = ret

  ret
end

#move(x, y, relative, refresh_flag) ⇒ Object

This moves the scroll field to the given location.



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# File 'lib/rndk/scroll.rb', line 358

def move(x, y, relative, refresh_flag)
  windows = [@win, @items_win, @shadow_win, @scrollbar_win]

  self.move_specific(x, y, relative, refresh_flag, windows, [])
end

#position ⇒ Object

See Also:



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# File 'lib/rndk/scroll.rb', line 222

def position
  super @win
end

#set(items, numbers, highlight, box) ⇒ Object

This sets certain attributes of the scrolling items.



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# File 'lib/rndk/scroll.rb', line 409

def set(items, numbers, highlight, box)
  self.set_items(items, numbers)
  self.set_highlight(highlight)
  self.set_box(box)
end

#set_bg_color(attrib) ⇒ Object

This sets the background attribute of the widget.



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# File 'lib/rndk/scroll.rb', line 376

def set_bg_color(attrib)
  Ncurses.wbkgd(@win, attrib)
  Ncurses.wbkgd(@items_win, attrib)

  unless @scrollbar_win.nil?
    Ncurses.wbkgd(@scrollbar_win, attrib)
  end
end

#set_highlight(highlight) ⇒ Object

This sets the highlight of the scrolling items.



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# File 'lib/rndk/scroll.rb', line 441

def set_highlight(highlight)
  @highlight = highlight
end

#set_items(items, numbers) ⇒ Object

Sets the scrolling items items. See Scroll#initialize.



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# File 'lib/rndk/scroll.rb', line 417

def set_items(items, numbers)
  return unless self.create_item_list(numbers, items)

  # Clean up the display.
  (0...@view_size).each do |x|
    Draw.writeBlanks(@win, 1, x, RNDK::HORIZONTAL, 0, @box_width - 2);
  end

  self.set_view_size(items.size)
  self.set_position(0)
  self.erase

  @left_char = 0
end

#unfocus ⇒ Object 



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# File 'lib/rndk/scroll.rb', line 521

def unfocus
  self.draw_current
  Ncurses.wrefresh @items_win
end