Brick.Widgets.List

This module provides a scrollable list type and functions for manipulating and rendering it.

Documentation

data List n e

List state. Lists have an element type e that is the data stored by the list. Lists handle the following events by default:

• Up/down arrow keys: move cursor of selected item
• Page up / page down keys: move cursor of selected item by one page at a time (based on the number of items shown)
• Home/end keys: move cursor of selected item to beginning or end of list

Instances

Functor (List n)

Foldable (List n)

Traversable (List n)

Named (List n e) n

Constructing a list

list

Arguments

:: n

The list name (must be unique)

-> Vector e

The initial list contents

-> Int

The list item height in rows (all list item widgets must be this high)

-> List n e

Construct a list in terms of an element type e.

Rendering a list

renderList

Arguments

:: (Ord n, Show n)

=> (Bool -> e -> Widget n)

Rendering function, True for the selected element

-> Bool

Whether the list has focus

-> List n e

The List to be rendered

-> Widget n

rendered widget

Turn a list state value into a widget given an item drawing function.

Handling events

handleListEvent :: (Show n, Ord n) => Event -> List n e -> EventM n (List n e)

Lenses

listElementsL :: forall n e e. Lens (List n e) (List n e) (Vector e) (Vector e)

listSelectedL :: forall n e. Lens' (List n e) (Maybe Int)

listNameL :: forall n e n. Lens (List n e) (List n e) n n

listItemHeightL :: forall n e. Lens' (List n e) Int

Manipulating a list

listMoveBy :: Int -> List n e -> List n e

Move the list selected index by the specified amount, subject to validation.

listMoveTo :: Int -> List n e -> List n e

Set the selected index for a list to the specified index, subject to validation.

listMoveUp :: List n e -> List n e

Move the list selected index up by one. (Moves the cursor up, subtracts one from the index.)

listMoveDown :: List n e -> List n e

Move the list selected index down by one. (Moves the cursor down, adds one to the index.)

listInsert

Arguments

:: Int

The position at which to insert (0 <= i <= size)

-> e

The element to insert

-> List n e

-> List n e

Insert an item into a list at the specified position.

listRemove

Arguments

:: Int

The position at which to remove an element (0 <= i < size)

-> List n e

-> List n e

Remove an element from a list at the specified position.

listReplace :: Vector e -> Maybe Int -> List n e -> List n e

Replace the contents of a list with a new set of elements and update the new selected index. If the specified selected index (via Just) is not in the list bounds, zero is used instead.

listSelectedElement :: List n e -> Maybe (Int, e)

Return a list's selected element, if any.

listClear :: List n e -> List n e

Remove all elements from the list and clear the selection.

listReverse :: List n e -> List n e

Reverse the list. The element selected before the reversal will again be the selected one.

Attributes

listAttr :: AttrName

The top-level attribute used for the entire list.

listSelectedAttr :: AttrName

The attribute used only for the currently-selected list item when the list does not have focus. Extends listAttr.

listSelectedFocusedAttr :: AttrName

The attribute used only for the currently-selected list item when the list has focus. Extends listSelectedAttr.