Register multiple event listeners with the same callback in one call #1231
Conversation
Passing an array of event types in vjs.on, vjs.one or vjs.off will create a listener for each one of the given events instead of calling vjs.on multiple times with the same callback.
….on, vjs.one or vjs.off and creates a call for each type in the array
…t array and write unit tests for vjs.arrayForEach to make sure that the fallback function works as expected
…otation and use for() loop instead forEach() for the arrays for better performance
…iable instead of counting it in each loop
|
Thank you for submitting this! I just did a quick once over, but from what I can see this is a really clean PR with tests to boot...Awesome. |
|
Thank you! I will create soon another PR implementing this enhancement in cases like the one with the Loading Spinner. |
| * @param {Function} fn Event listener. | ||
| * @param {String} method Event method (on, off, one). | ||
| */ | ||
| vjs.forwardMultipleEvents = function( elem, type, fn, method ) { |
There was a problem hiding this comment.
By using the jsDoc comments and adding it to vjs it makes this a public function. I don't think it would get used outside of the core codebase so I think we could keep it private and allow closure compiler to mangle it. To make it public private you could change the name from vjs.forwardMultipleEvents to _forwardMultipleEvents and add the @private tag to the comment.
|
@themicp Are you still interested in making some of the updates listed here? Let me know if there's any outstanding questions I can answer. |
|
@heff I am sorry for the delayed response. I am still interested in finishing this PR, I will fix those notes in the next couple of days. |
|
No problem. Sounds good, thanks. |
moved vjs.arrayForEach in the vjs.arr object and rename it to vjs.arr.forEach, update the vjs.arr.forEach unit tests.
renamed forwardMultipleEvents to _forwardMultipleEvents since it's a private function and also update the comments, use vjs.arr.forEach instead of vjs.arrayForEach, don't export vjs.one, vjs.on and vjs.off.
|
I updated the PR with the things mentioned in the comments. Let me know if there is anything left. |
|
This looks ready to go to me. Will pull in soon. |
|
That's great, thank you! |
…video.js into review-themicp-feature/multiple-event-register
…-register Updates to videojs#1231 - multiple event listeners
|
Awesome, thanks for pulling those changes in. I'll get this merged in after the holiday weekend. |
There are cases where you want the same function to be called for many different events. For example take a look at the following code from the constructor of the Loading Spinner:
We want to run the function
vjs.bind(this, this.hide)for 5 different events and for that purpose we callplayer.on5 times which makes the code very long and ugly.From this, I came up with this feature/enhancement where you can call vjs.on with an array of events and attach the callback in all of them with a single call (passing an event as a string still works as before). With this feature the constructor of the Loading Spinner would look like this:
The same goes with vjs.one and vjs.off, too.
For the implementation of this feature I needed a method to run a function for each element of an array but Array.prototype.forEach() was not a good idea due to performance issues (http://jsperf.com/fast-array-foreach) so I created vjs.arrayForEach which does the same thing but using the for() loop.
I have also included comments, unit tests for all of my changes (including .arrayForEach()) and updated the exports file to export vjs.on, vjs.off and vjs.one to be able to access them using bracket notation from vjs. forwardMultipleEvents.