Features and usability: questions of curiosity and suggestions

[johnperry-math]

I've noticed a few things about some keyboard interaction and text inputs that prompt questions.

Mere curiosity

• Why use textarea for single-line text input, rather than just an input with type=text?

Enhanced features

• Some keyboard-related events could use more fields. The other day I subclassed one of the widgets (don't recall which) so that oninput (I think?) returned more than just the value. For backward compatibility, though, I'm not sure this is feasible.
• A request_focus() method that wraps the .focus() method for HTML elements would be very convenient. Consider a document with multiple TextInputs; when onchange occurs in one, the handler could automatically focus on the next one, rather than forcing the user to do that somehow.
• Is it worth allowing keyboard events on more widgets, or incorporating intuitive behavior when the widget is focused? For example, when the Slider widget is focused, it makes sense to have it respond to onkeydown; I have an ExtendedSlider that uses this to:
  • Move left or right when the arrow key is pressed.
  • Move to a position according to a number pressed. (I don't think this should be a default behavior, but it's an example.)