[mproud]

How about when users accidentally click too much, or they believe the first click didn’t register?

I am still reminded of a keynote where Steve Jobs was demoing how much faster PDF documents would display on the newer macOS. So he had engineers put a button in for him to click that would scroll through the PDF on the screen, and he accidentally clicked it more than once. Steve wondered aloud if it would scroll all the way through twice… and sure enough, it buffered the process! He had to wait for it go all the way back up and scroll through a second time!

Steve saved grace by telling the audience that, even with moving through the document a second time, altogether it was still faster than PDFs had been in the last version of the OS.

[mcv]

Debouncing exists for a reason. Sometimes when a button is clicked twice, you want it executed twice, sometimes you don't. Distinguishing which is better in which situation is not trivial.

At the very least, you should consider which is appropriate for which situation, what if, in your UI, for some buttons one is the obvious choice, for others it's the other, but for some it's not so clear, and both behaviours are defensible? Now you've got an inconsistent UI.

I have no good solution for this.

[efficax]

a button that debounces requests should be disabled until the action is complete instead, so you can only click it once until it is ready to be clicked again. debouncing button clicks is a design failure (it makes more sense for things like requests that happen during typing, where you don't want to stop the feedback)

[Findecanor]

I think that if you'd need to debounce requests, it would be better to put it in a pressed and/or highlighted state until the button is ready again. Then you'd indicate to the user that the press was successfully received and that pressing it again won't do any good.

The buttons in an elevator panel typically work this way. They each light up to confirm a pending request to reach a floor. They each turn off when its floor has been reached. And while a button is lit up, pressing it does nothing.

[simonkagedal]

They should be toggles! Every now and then I will press the wrong button and will have to wait for the elevator to stop, open doors, close doors at a floor no one wants off on.

I mean, I haven’t done the usability research, probably there are some good reasons for it’s not a good idea to just make them toggles, but I would find it neat.

[flusensieb]

Imagine the backlight of the button is broken. Now you enter the elevator and want to go to floor 7, while someone else already pressed the button ;)

[Someone]

There always will be time between the first click and the time the button gets disabled and even more time before the visual representation of the button gets updated to reflect that. Keeping that time so short that it is impossible for a human to click the button again can be very hard.

It would help if GUI elements had a property “automatically disable on click”, removing the need for the “on click handler” to disable the button (in exchange for adding the need to explicitly re-enable it).

I don’t remember seeing GUI libraries that do that, though.

That probably is because it would confuse users if buttons visually get disabled when they click them.

So, the best answer is to visually keep the button enabled, but ignore rapid further clicks. That’s debouncing.

[QuercusMax]

This is a fundamental misunderstanding of how GUIs must necessarily work. There should be no possibility of race conditions if you understand the threading model.

The visual representation updating (greying out button) is a result of disabling the button, not the same thing. In virtually every GUI toolkit I've ever used there is the concept of the main UI thread, and everything that happens (input and display updates) necessarily has to go through that single thread in order to ensure correctness. (This applies to browsers, too.) That's why input goes into a queue, so you can easily do things like:

(All on the main UI thread):

  - Receive click event 1: disable button, start background process. Possibly redraw button UI *but it doesn't matter because the UI display is not the state, it's just a view*.

  - Receive click event 2: nothing happens, button is disabled

  - Background process finishes, posts update to re-enable the button

  - Receive click event 3: disable button, start background process, etc.

[dvdkon]

Of course, it's never impossible for the user to click a button. They can click on anything under their cursor. The key is giving them feedback to show them what their clicks will do or just did. If you can update the visuals within a frame or two, that's already fast enough to give that feedback.

[kccqzy]

It’s really common for people to accidentally click a button twice. Yeah that’s what denouncing is for.

My favorite example of doing it wrong is a log in form: if the login button is clicked twice, the server would reject the login because the first click has already used up the one-time token so the user gets an error page.

But I think the biggest problem is that people either apply denouncing to all buttons in a UI (like turning it on within the framework they are using) or apply denouncing to nothing. So there really isn’t a culture for carefully considering which situations warrant which.

[PunchyHamster]

the correct action is not to debounce but instead of error page see user already logged in in previous request and continue

[jonahx]

I think the better solution for a web page login form specifically is to disable the button "onPressDown", so this error path is impossible.

For users with JS disabled, your solution seems good.

[stavros]

The correct action is to disable the button while the request is in flight so it can't be clicked a second time. Otherwise you won't see "user already logged in", because the user won't be logged in until the previous request returns (a race condition).

[LordDragonfang]

If you have a race condition, "correct action" is to solve that, because you shouldn't be papering over server-side bugs with client-side Javascript (and yes, it's a bug, because I shouldn't see an error page if I press the back button after logging in (and trying to navigate to what I was doing before logging in) either, which I still see quite often)

[stavros]

How would you solve this on the server?

[Timwi]

It seems somewhat clear to me. You want it executed twice if and only if the operation isn't idempotent. Can you give an example where you think both behaviors are equally defensible?

[RossBencina]

I guess the downvotes signal disagreement, but I value the conversation in spite of disagreeing with you. I'm not sure idempotence is the only concept in play.

If the operation is idempotent, well, clicking twice doesn't do anything. I'd still want to see the button light up to signal that the UI is alive, or the button could grey out or enter a "latched" state like a radio button if there is nothing to be done. Behind the scenes suppressing command propagation is an implementation detail and the trade off is between front-end complexity and redundant command execution overhead.

If the operation is not idempotent I can give you separate examples where different behaviors are appropriate:

1. A button used to increment a counter (e.g. quantity of GPUs to buy) should increment on every click, even if the UI response is delayed. The user can count clicks, and there is going to be a decrement button to reverse any error. You do not want the user waiting around guessing whether the software is still processing the remaining clicks. As a rule, so long as the operation is non-destructive (e.g. inc and dec buttons, all operations reversible/undoable, etc.) every user interaction can and should be actioned.

2. A button used to perform an irreversible action, i.e. a "commit", such as placing the order to purchase a GPU, should only perform that operation once. I would not call this an idempotent operation, certainly not with respect to your bank balance.

[Timwi]

The button to place an order should 100% be idempotent. There's one order you're constructing in your shopping cart, perhaps with an internal ID, and the irreversible “commit” button should place that order, not create two separate orders.

[account42]

Debouncing also has nothing to do with the animation shown on the screen so tying the debounce time to the animation is almost certainly wrong no matter what those tradeoffs are.

[lucumo]

> How about when users accidentally click too much, or they believe the first click didn’t register?

I was really confused at their mention of accessibility, because my mind jumped to people with hand tremors who would double press when they intended only one press.

And then, of course, there are the people that double-click every button. To handle that, disabling a submit button in the onclick is very common.

[edyg]

Got here to comment on the same. Was really surprised how the narrative turned at this point

[Self-Perfection]

From the article:

> The Nothing Phone button gives you a tap confirmation via both haptics and sound, and then ignores the tap if a previous rotation is still animating.

This is the issue. Number of performed actions has to be equal to number of times the app identified that button press was registered. Debouncing is a good practice, but if it is used then debounced taps must not produce feedback.

[atoav]

Button ≠ Button. People like to believe they should all be the same, but they really should not be.

On physical keyboards we already have three different kinds: normal buttons, modifier keys (shift, etc) and toggle keys (caps lock).

High stakes rare actions can require special button designs. E.g. on a black magic cinema camera the button that formats the memory card needs to be held for three second while it visually counts down. This gives a small delay during which the user can decide: "Fuck this is the wrong memory card!" and cancle.

The downside is that some imaginary power user that uses the camera only to format a stack of SSDs will get burdened. You have to decide which is more common and make a decision.

[embedding-shape]

I'm no longer the Apple/Mac/Jobs fan-boy I once was in my earlier days, but I do miss the Apple presentations that felt like they were run by a human being wanting to show off cool stuff.

I couldn't even finish the last Apple presentations as it all feels so stiff, inhuman and run by suits, they all seem like robots scared of diverging from the holy script who will get fired if they display emotions and humanity.

Off-topic perhaps, but got reminded how delightful even the somewhat messy ad-hoc presentations from Jobs were.

[vishnugupta]

I agree 100%. I stopped watching after iPhone 15 event or maybe M2.

Absolutely everything seems scripted including hand movements, shifting of postures, smiles..the whole works.

Now I just wait for the press release and that’s that.

[port11]

The scripted talks in front of fancy backgrounds do make it unpalatable, it’s just a fancier version of corporate slideshows. I suppose trillion-dollar companies aren’t as willing to take risks.

[pixelatedindex]

> I suppose trillion-dollar companies aren’t as willing to take risks.

Which to me makes no sense, surely you have some budget for risks if you are a 1T company? I suppose their risks are more moonshots to some degree like the Apple Car but nevertheless, I do miss the old presentations.

[amelius]

Apple keeps solving the same old problems. Why are we still talking about how well their buttons behave?

[bshacklett]

Point to another source that does it as well or better. The problems might have been solved, but it seems the majority of the industry continues to ignore them.

That said, I’ve been using Niri with Noctalia for months now, and I’m continuously delighted by the lack of astonishing behavior.

[embedding-shape]

If anything it seems to be getting worse with each iteration for long time. I guess I'm cautiously optimistic they'll get back closer to their roots with some high-level change, but really don't care that much about it these days either...

[bshacklett]

Truly. The number of times I’ve been surprised by something on newer macOS versions and thought: “I think this used to go against the human interface guidelines” is crazy. IMO: the first major sign of the downfall was when stealing focus on OS X became common.

Jobs had no problem calling BS on annoying behavior. Unfortunately we’ve completely lost that, and Apple is no longer the bastion of usability that it once was.

[chrismorgan]

That was a common problem in JS-based menu opening and closing, long ago: they were treated as animations and queued. This was sometimes quite ludicrous.

Nowadays, you use transitions instead, which are not queued. But I still very occasionally see things that use queued animations.

[krautsauer]

"How about"? These situations might exist, but this clearly isn't one. Two reasons:

1. "The Nothing Phone button gives you a tap confirmation via both haptics and sound, and then ignores the tap […]"

2. There is a really good reason to tap this button 3 times in a row.