This repository has been archived by the owner on Jul 27, 2022. It is now read-only.
Clean up keyboard handling #1060
Assignees
Labels
Comments
natduca
added a commit
that referenced
this issue
Jul 1, 2015
The old key handling architecture had a ton of nasty hacks for whether the timeline is listening to keys (listensToKeys). This mess stems from a few things: - Some of our components have local hotkeys that need to get called even when they dont have keyboard focus. For instance, the wasd keys should work in the track view even when some other panel has focus. - Sometimes the toplevel timeline view doesn't have keyboard focus. In the single-timeline-view-fills-the-screen use cases, we still want the timeline view to get foucs. The old architecture addresses this by having tons of global key event listeners and then piles of hacks to turn off the global behavior when we think that the timeline-view is not focused. The new architecture is more modular. Individual components that want to have hotkeys create and attach a <tr-ui-b-hotkey-controller> element. They then add their local hotkeys to that object. Hotkeys are strongly typed, so that we can generate help text automatically down the road. Internally, the hotkey controllers talk to each other to find the topmost controller. That topmost controller creates the actual keypress/down listeners, and then does all event dispatch for all controllers in that subtree. Notably, the mouse mode selector does not use the new hotkey controller. This is because the mode selector is quirky: instead of plain hotkeys, its state changes in direct response to modifier keydown/key up events. Rather than complicating the hotkey controllers design to accommodate the mouse mode selectors stuff, it directly listens to the modifier keys: to do this and avoid leaking the selector object due to document-owning-a-backpointer-to-an-element, we rewrite the component to be polymer, which allows us to register for document listeners in the attached/detached lifecycle callbacks. BUG=#1060 Review URL: https://codereview.appspot.com/239280043
Sign up for free
to subscribe to this conversation on GitHub.
Already have an account?
Sign in.
The keyboard handling code in trace viewer is a nightmare: we have a few global document key listeners, and then a pile of hacky code to fix complications arising from this basic mistake.
We should fix it.
The text was updated successfully, but these errors were encountered: