Feature request: continuous keydown events

[jinjor]

Currently Keyboard module does not have API for continuous keydown events. Keyboard.isDown is fired only when value is changed, but I sometimes need many events when I keep keys pressing.

For example, I am implementing Undo/Redo triggered by ctrl+Z/ctrl+Y. I usually undo 100+ steps by keep ctrl+Z pressing, but this feature cannot be implemented using current API.

[halfzebra]

You can achieve that by doing something like this, along with filtering for required key codes:

import Keyboard
import Signal
import Time
import Debug
import Graphics.Element exposing (show)


main =
  Keyboard.keysDown
  |> Signal.sampleOn (Time.fps 30)
  |> Signal.map show

Does that really require a core feature?

[halfzebra]

You can achieve that by doing something like this, along with filtering for required key codes:

import Keyboard
import Signal
import Time
import Debug
import Graphics.Element exposing (show)


main =
  Keyboard.keysDown
  |> Signal.sampleOn (Time.fps 30)
  |> Signal.map show

Does that really require a core feature?

[jinjor]

Thanks, but I need different behavior. When some key is keeping pressed, The first event is fired immediately and the rest are fired after some interval. Like this:

a.......aaaaaaaaaaaaaaa

Also, I read the source and found the down state is made by filtering original events. I think it's more natural to use the original events than to reproduce new events.

[jinjor]

Thanks, but I need different behavior. When some key is keeping pressed, The first event is fired immediately and the rest are fired after some interval. Like this:

a.......aaaaaaaaaaaaaaa

Also, I read the source and found the down state is made by filtering original events. I think it's more natural to use the original events than to reproduce new events.

[Warry]

Repeating keys can be retrieved with keyup, but the core only supports keydown. I agree with @jinjor that it should be the developer's choice and should be available there.

Maybe we should expose document's events withOptions, just like for Html, where we can listen to an event by giving a string and a decoder.

[Warry]

Repeating keys can be retrieved with keyup, but the core only supports keydown. I agree with @jinjor that it should be the developer's choice and should be available there.

Maybe we should expose document's events withOptions, just like for Html, where we can listen to an event by giving a string and a decoder.

[evancz]

I think this is solved in elm-lang/keyboard

[evancz]

I think this is solved in elm-lang/keyboard