It seems to be a consistent browser behaviour that when the user drags out of a a element, to avoiding clicking on releasing the mouse button, that that element retains focus until the user clicks somewhere else.
Is there an accessibility related reason for this?
It seems to be a common user behaviour (interaction) to negate a click 'halfway through' and, in MacOS, at least, is the default menubar mouse behaviour.
I guess I'm looking for a way to force a drop of focus on mouseout but I don't know whether this is bad for accessibility.
Incidentally this is visually bad ugly either button is used as a UI object or an a is styled as a button.
Whether the focus remains on the button/link or if you force it away will not cause an accessibility issue with regards to WCAG conformance. It does not fail any guidelines.
It comes close to failing WCAG 3.2.2 On Focus but I think the timing of your events technically makes it pass. The mousedown event causes the focus event and you are not doing anything with the focus event. It's when the mouseup event happens that you're trying to move focus so in theory, you are not changing the context on the focus event.
I'm not sure that means you should do what you have proposed from a UX perspective but there probably aren't a lot of people that rely on the default behavior.
Related
I've noticed that when I have long list elements in JQuery Mobile and I try to scroll them, I accidentally select an element. Overall the act of scrolling tends to get confused with tapping.
I did some comparison to a native iOS list and here is the difference:
In JQueryMobile, as long as you do a MouseDown and MouseUp on an element, it is considered a click. It doesn't matter if you've scrolled inbetween the events.
In iOS, if you do a MouseDown on an element and then scroll at all, the MouseDown is effectively canceled. This allows you to tap on something, scroll the page up and release without it being considered a click.
Has anyone noticed this and/or developed a patch for it? If not, any suggestions on a fix?
So my problem is that I have a TJvDocServerForm with an image inside, now all functionality works when its pinned, however when its unpinned and I try to use the mousewheel to zoom, the form hides straight after the zoom operation.
The zoom works through a scrollboxmousewheel event that triggers a
timer.
The timer then redraws the larger/smaller image through my own
image class when movement on the mousewheel has stopped.
Through break points it appears the draw is causing the form to
hide.
I believe this has got something to do with the focus being lost, however resetting the focus back to he form directly after the draw does not stop the hide as it has already been told to hide.
Is there a way to somehow lock the form from hiding until after the image has been redrawn?
This functionality (the unpinning thing) is rarely used. This code is extremely complex, and changing it is not recommended unless you like causing regressions. How common is the combination of mouse wheel + unpinning? So rare, I'd let it go, if I were you. If you can live without the unpin feature at all, just change dock styles. Personally I hate the unpinned state and I use a dock style that doesn't even support it. The unpinned "zoom away" animation may be directly linked to the focus-loss. You could store that state, wait until the next time through the message loop and then trigger the animation, if you wanted to, but even I, who have done lots of work in JvDocking source code, would be hesitant to try it.
I'm wondering if there's an easy way to tell which input device triggered a particular GUI event.
For example: A TButton.OnClick event gets fired. Did the user trigger it with a keyboard press (shortcut, Enter key for default button, space key for a focused button, etc.) or was it triggered with a mouse click? Is there any easy way to tell?
The reason I'd like to know is so that I can implement keyboard usage hints into some of our applications when the user uses the mouse to initiate actions that could also be done with the keyboard. Our systems on the shop floor are in pretty dusty/dirty environments, and mice tend to not hold up so well in them. Also, in many cases, there's simply not that much room for a mouse to be used. (No, keyboards without numeric keypads is not a solution. They're relied on too heavily.)
However, since our apps run in Windows, users tend to simply use the programs like they would at home -- with a mouse. There's nothing particularly wrong with that, but we've worked hard to optimize the input workflow to be keyboard friendly as well. It'd be nice if there was a low-impact way to indicate to our users that there's a way for them to do the things they're doing without having to grab the mouse.
There's no way to tell from within OnClick. However, you can also attach events to a control that will fire when the mouse rolls over it, which would probably be more appropriate for what you're trying to do anyway. Take a look at the OnMouseEnter and OnMouseLeave events. Also, if you really want something specific to happen when the mouse is clicked, you can attach it to OnMouseUp.
Context: Web app on MobileSafari/iPad, both full-screen and embedded in iframe
Goal: Technique that provides custom event handlers for Press and Tap but not Pinch (zoom) or Drag (scroll/pan). We want to provide custom behavior for Press, but to let Safari handle Scroll/Pan/Zoom still.
Problem: The two goals seem to be mutually exclusive. To prevent the default behavior for a Press gesture, event.preventDefault must be called in immediate response to ontouchstart. However, to let the default behavior proceed on a Drag, we must not call event.preventDefault on the initial ontouchstart. Once preventDefault is called, there is no way of getting the default behavior back during that gesture sequence (i.e. until all fingers come off). Drag is not recognized until some movement has occurred.
Drag is illustrated as the simplest example, but we care about getting the default behavior for Pinch and Double-tap as well. We never want the default MobileSafari Press behavior of "Copy Image" or selecting text.
Attempts thus far:
Save the ontouchstart event and, after a timeout, call preventDefault on it later (just before Press would be recognized). No effect.
Listen for 'oncontextmenu'. Nope, the default Press behavior is not being signaled or routed through this event.
Prevent the default in all of our ontouch* handlers, and then when we recognize a Drag/Pinch gesture, simulate new events using initTouchEvent and/or initGestureEvent. The programmatically created events hit all of our callbacks, but Safari seems to pay no attention to them, triggering no default behavior.
Break up Safari's Press recognition with a fake move. Safari cancels a press on the slightest move, but we allow for a bit of slop. Simulating a move event (as above) just after the ontouchstart does not cause Safari to fail to recognize Press if the finger is not moved "for real".
We have a fully featured set of gesture recognizers implemented (in Javascript, ontouch*) in the style of Apple's native iOS gesture recognizers. We have no problem recognizing any gestures, we just don't know of a good way to replicate the Zoom/Pan/Double-tap behavior that Safari provides for free.
We don't need code; we're looking for any theoretical solution (beyond "just implement pan/zoom yourself too", though if you have a slick way of doing that we're interested) that leads to reasonable success. We're also interested in learning about other similar attempts to do this - surely we can't have been the first to try this?
Alternate TL;DR: Is there any way to prevent a default Press (also known as tap-and-hold) other than in touchstart?
Success: Prevent "default press" behavior entirely through CSS instead of preventDefault. This answer was provided by Safari Technologies Evangelist Vicki Murley over here (registration required)
I see in your stackoverflow post that
you say your ultimate goal is that:
"We never want the default
MobileSafari Press behavior of "Copy
Image" or selecting text."
These behaviors can be disabled in CSS
(+ one bonus property, since people
often want to turn off the highlight
if they're turning off these other
behaviors):
/* behavior */
-webkit-user-select: none; /* disable cut copy paste */
-webkit-touch-callout: none; /* disable callout, image save panel */
-webkit-tap-highlight-color: transparent; /* "turn off" link highlight */
Commentary: We assumed that Safari's Press behavior was event-based, not driven by CSS. Calling preventDefault ontouchstart does cancel the press behavior (which is what led us astray, really), but that seems to be an unintended side-effect. Really, Mobile Safari does not execute a "press event" so much as "CSS on press".
Disabling the Press behavior with CSS has allowed us to once again call preventDefault only where and when we actually need it.
Ugly Possibility: Don't prevent a press - make a default press do nothing. Try to use a glass-pane div that catches all touches and doesn't prevent anything on touchstart.
Divs do have default Press behavior (some kind of selection), but perhaps that can be turned off, not via preventDevault but via <body style="-webkit-user-select:none">? ref
This would mean we'd have to do our own hit-testing to determine what DOM nodes to pass our recognized events to, since we can't just let events bubble up the DOM ancestor chain.
I have the following situation
I handle when the left mouse button is pressed in my Silverlight app and do some things while the mouse is held down and the mouse moves. When the left button is released, I turn off the flag that's telling it to do the stuff and the mouse movement handler then no longer does the stuff.
The problem is: if the user is in the control area, pushes the left button down and moves out of the control area, then releases the button and reenters, the MouseLeftButtonUp event never fires and the processing continues until the user clicks the mouse.
My temporary fix was to turn the mouse flag off on MouseLeave but that's not really what I'm going for. I'd like to check to see the mouse's left button state in the MouseEnter event, but I don't know of a way to do that.
Does anyone know of a way I can access the mouse button state outside of the press events in Silverlight 3? Thanks,
Update
After thorough research, it doesn't look like this is possible in Silverlight 2 (and probably 3.) I found this link. If anyone knows of a workaround, please let me know.
What you need to do can be accomplished with the UIElement.CaptureMouse method:
http://msdn.microsoft.com/en-us/library/system.windows.uielement.capturemouse%28VS.95%29.aspx
When a UIElement has captured the mouse, it will continue to receive mouse events even if the mouse leaves the Silverlight control.