UIElement:next_focusable

Advanced

Returns the next focusable element from this one in the specified direction.

You may override this method when implementing containers that can interpret directional navigation to move focus between elements.

Usage

ui_element:next_focusable(from_element, player_index, direction)

Arguments

Name	Type	Description
from_element	UIElement	Child element inside this one to navigate from.
player_index	number	Number identifying the player whose inputs to consider.
direction	Direction	Navigation direction.

Returns

Name	Type	Description
element	UIElement | nil	Next focusable element in this direction, if any.

Examples

This example is a slightly simplified version of the next_focusable implementation for HorizontalList elements:

HorizontalList.next_focusable = function(self, from_element, player_index, direction)
  local from_index = table.index_of(self._children, from_element);
  local delta = 0;
  if direction == "down" then
    delta = 1;
  elseif direction == "up" then
    delta = -1;
  else
    return HorizontalList.super.next_focusable(self, from_element, player_index, direction);
  end
  local to_index = from_index + delta;
  to_element = self._children[to_index];
  while to_element do
    local next_focusable = to_element:first_focusable(player_index);
    if next_focusable then
      return next_focusable;
    end
    to_index = to_index + delta;
    to_element = self._children[to_index];
  end
end