creating homemade scrollbars in web pages - javascript

For years I have had a problem using javascript and jquery to control things like homemade scrollbars. I use mousedown to set a "dragging" variable to true, save the initial mouse position, and then use mousemove to track the mouse and set the div position. I condition everything on "dragging" so that once the user lets go of the mouse, or moves far enough away, then "dragging" is cleared and everything stops tracking.
The problem is, I have trouble finding out for sure when they let go of the mouse. I use mouseup and mouseout of course, but this has two problems. One is that I want the user to be able to wander outside the div being scrolled a small amount, like 10 pixels, without losing the tracking. The other problem is that sometimes I miss an event and "dragging" stays set and the mouse gets "stuck to the div" and they have problems letting go.
I need a solution. It can either be some plugin or a coding technique. I have used a number of different techniques over the years but I've never gotten a simple perfect solution.

Related

Is there any way to force the position of the mouse to a certain point on the screen? (for camera control purposes) [duplicate]

I'm building a HTML5 game and I am trying to put the mouse cursor over a certain control on a specific event so that moving in a specific direction always has the same result. Is this possible?
You cannot move the mousepointer with javascript.
Just think about the implications for a second, if you could ;)
User thinks: "hey I'd like to click this link"
Javascript moves mousecursor to another link
User clicks wrong link and inadvertently downloads malware that formats his c-drive and eats his candy
Run a small web server on the client machine. Can be a small 100kb thing. A Python / Perl script, etc.
Include a small, pre-compiled C executable that can move the mouse.
Run it as a CGI-script via a simple http call, AJAX, whatever - with the coordinates you want to move the mouse to, eg:
http://localhost:9876/cgi/mousemover?x=200&y=450
PS: For any problem, there are hundreds of excuses as to why, and how - it can't, and shouldn't - be done.. But in this infinite universe, it's really just a matter of determination - as to whether YOU will make it happen.
I would imagine you could accomplish placing the mouse cursor to a given area of the screen if you didn't use the real (system) mouse cursor.
For instance, you could create an image to act in place of your cursor, handle an event which upon detecting mouseenter into your scene, set the style on the system cursor to 'none' (sceneElement.style.cursor = 'none'), then would bring up a hidden image element acting as a cursor to be anywhere you like with in the scene based on a predefined axis/bounding box translation.
This way no matter how you moved the real cursor your translation method would keep your image cursor wherever you needed it.
edit: an example in jsFiddle using an image representation and forced mouse movement
Great question. This is really something missing from the Javascript browser API. I'm also working on a WebGL game with my team, and we need this feature. I opened an issue on Firefox's bugzilla so that we can start talking about the possibility of having an API to allow for mouse locking. This is going to be useful for all HTML5/WebGL game developers out there.
If you like, come over and leave a comment with your feedback, and upvote the issue:
https://bugzilla.mozilla.org/show_bug.cgi?id=630979
Thanks!
You could detect position of the mouse pointer and then move the web page (with body position relative) so they hover over what you want them to click.
For an example you can paste this code on the current page in your browser console (and refresh afterwards)
var upvote_position = $('#answer-12878316').position();
$('body').mousemove(function (event) {
$(this).css({
position: 'relative',
left: (event.pageX - upvote_position.left - 22) + 'px',
top: (event.pageY - upvote_position.top - 35) + 'px'
});
});
So, I know this is an old topic, but I'll first say it isn't possible. The closest thing currently is locking the mouse to a single position, and tracking change in its x and y. This concept has been adopted by - it looks like - Chrome and Firefox. It's managed by what's called Mouse Lock, and hitting escape will break it. From my brief read-up, I think the idea is that it locks the mouse to one location, and reports motion events similar to click-and-drag events.
Here's the release documentation:FireFox: https://developer.mozilla.org/en-US/docs/Web/API/Pointer_Lock_APIChrome: http://www.chromium.org/developers/design-documents/mouse-lock
And here's a pretty neat demonstration: http://media.tojicode.com/q3bsp/
You can't move a mouse but can lock it.
Note: that you must call requestPointerLock in click event.
Small Example:
var canvas = document.getElementById('mycanvas');
canvas.requestPointerLock = canvas.requestPointerLock || canvas.mozRequestPointerLock || canvas.webkitRequestPointerLock;
canvas.requestPointerLock();
Documentation and full code example:
https://developer.mozilla.org/en-US/docs/Web/API/Pointer_Lock_API
Interesting. This isn't directly possible for the reasons called out earlier (spam clicks and malware injection), but consider this hack, which creates an impression of the same:
Step 1: Hide the cursor
Let's say you've a div, you can use this css property to hide the real cursor:
.your_div {
cursor: none
}
Step 2: Introduce a pseudo cursor
Simply create an image, a cursor look-alike,and place it within your webpage, with position:absolute.
Step 3: Track actual mouse movement
This is easy. Check internet on how to get real mouse location (X & Y coordinates).
Step 4: Move the pseudo cursor
As the actual cursor move, move your pseudo cursor by same X & Y difference. Similarly, you can always generate a click event at any location on your webpage with javascript magic (just search the internet on how-to).
Now at this point, you can control the pesudo cursor the way you want, and your user will get the impression that the real cursor is moving.
Fair Warning: Do not do it. No one wants their cursor or computer controlled this way, unless if you've some specific use-case, or if you are determined to flee your users away.
You can't move the mouse pointer using javascript, and thus for obvious security reasons. The best way to achieve this effect would be to actually place the control under the mouse pointer.
Couldn't this simply be done by getting actual position of the mouse pointer then calculating and compensating sprite/scene mouse actions based off this compensation?
For instance you need the mouse pointer to be bottom center, but it sits top left; hide the cursor, use a shifted cursor image. Shift the cursor movement and map mouse input to match re-positioned cursor sprite (or 'control') clicks When/if bounds are hit, recalculate. If/when the cursor actually hits the point you want it to be, remove compensation.
Disclaimer, not a game developer.

Adobe Animate CC Canvas mouse actions on the stage are laggy and intermittent

In Adobe Animate CC HTML5 Canvas (createJS), I'm trying to do something very simple, to trigger an animated rollover when the entire stage of an ad is moused over, and to trigger an animated rollout when the mouse leaves the stage. It should be very simple, but it's not. Using mouseenter and mouseleave on the stage is laggy and only works intermittently. It's the same with mouseover and mouseout.
Here's the code that's laggy and intermittent:
stage.addEventListener("mouseenter", fl_MouseOverHandler.bind(this));
stage.addEventListener("mouseleave", fl_MouseOutHandler.bind(this));
function fl_MouseOverHandler(){
this.btnOverAnim.gotoAndPlay("on");
}
function fl_MouseOutHandler(){
this.btnOverAnim.gotoAndPlay("off");
}
I also tried mouseover and mouseout on a button the entire size of the stage and I got the same issue. (Also doing it this way doesn't work at all from inside a frame, and the ad is served inside a frame). I put the var frequency way up to 90 to see if that would help with the lagging, it didn't.
This was the simple mouseover / mouseout code I tried:
var frequency = 90;
stage.enableMouseOver(frequency);
this.bgCta.addEventListener("mouseover", fl_MouseOverHandler.bind(this));
this.bgCta.addEventListener("mouseout", fl_MouseOutHandler.bind(this));
On the createJS website it says "You can monitor whether the pointer is over the canvas by using stage.mouseInBounds AND the mouseleave / mouseenter events." So I'm wondering if using stage.mouseInBounds will help (but I can't find an example anywhere of how to use it). But I actually don't think it'll help because I think this whole problem is about createJS not reading where the mouse is fast enough.
Does anyone know how to fix this lagginess and intermittent firing? A work around? Why does createJS not just monitor the mouse events constantly like pure js?
Also mouseenter and mouseleave on the stage in createJS do not work on tablets or mobile and that's a problem, so it would be better to do this with mouseover and mouseout on a button the entire size of the stage. I did try using mouseover and mouseout and having 3 pixels space around the button between the edge of the button and the edge of the ad banner, this helped, but it was still firing intermittently.
Your thoughts and ideas please.
Mouseover checks are expensive. A canvas is essentially just a bitmap, so EaselJS can't use mouse events from the browser (you just get one for the entire canvas). Instead, mouseover in EaselJS requires every element to be drawn to a 1x1 pixel canvas, and then checked for fill. This gives pixel-perfect detection, but is costly if you are either checking a lot of content, or checking too often.
Reduce your frequency:
It looks like you have set the frequency to 90. This is really high (11 ms between checks, which is basically trying to achieve 90 fps). The default is 10, which is slower than a good framerate, but fast enough to feel responsive. You can probably bring it down to 20 or so to give you a peppy check without it being unnecessarily high.
Modify interactivity: Another thing you can do is filter out exactly what gets checked. By default, all display objects get checked -- but you can reduce this by turning off mouseEnabled on anything you don't care about (omitting them from the check), and turning off mouseChildren on containers that you want to treat as a single object (so something like a complex button is drawn once, instead of all its contents being drawn individually).
// Example
myBackground.mouseEnabled = false;
myButton.mouseChildren = false;
Hope that helps!
Friends, I know this was asked 4 years ago, but the lagginess in Adobe Animate CC V.21 is no different (horrible) regarding mouseenter, mouseleave, mouseover and mouseout. After 10 times of rolling over/out the page becomes unresponsive. I was able to alleviate this using stage.mouseInBounds on a setInterval. The original poster could not find an example, so here is what I did:
// Place this in a keyframe on the timeline where the named cta exists.
setInterval(function(scope){
if(stage.mouseInBounds){
createjs.Tween.get(scope.cta).to({scaleX:1.1, scaleY:1.1}, 150);
}
else{
createjs.Tween.get(scope.cta).to({scaleX:1, scaleY:1}, 150);
}
}, 150, this );
Make sure to pass this into the end of the setInterval function as an argument for the callback function as to not lose scope. I am guessing this can be reworked to use gotoAndPlay() on the timeline, in this instance the built-in tweener for CreateJS sufficed for what I needed.

Measure swipe distance

This question has been probably asked many times but I can't actually find the answer nor here nor on Google. Probably I'm searching it with wrong words, so I decided to ask here on StackOverflow.
I'm using Hammer.js to handle the mobile gestures on the current website and what I'd like to do now is moving the divs horizontally as much as the thumb moves (like the Facebook's app gallery, for example).
I thought I can achieve it getting the coordinates X,Y of the point where the swipe event is recognized and then animate the move between the current viewport and the next "overflow hidden" div. What I'm missing is: which is the event listener that would listen at every thumb move so that I can calculate the distance in pixel between the current point and the starting point, automatically updating the value for the animate function?
the event you are looking for is touchmove

How to enable dragging off the control to scroll and extend the selection

I'm creating a custom scrolling control using HTML's Canvas that behaves a little like a spreadsheet grid. I have most standard cursor control behaviors set up, including using the mouse or arrow keys to extend the selection.
What I'd like to do next is allow the user to extend the selection by clicking and dragging off the canvas. I don't need help with the actual code, but I'd like to know if anyone has programmed something like this before, and if so, how did they approach it? Here are the ways I can think of:
Track the mouse's general direction while over the control, and on mouseLeave+mouseDown set up a timer to scroll that direction until mouseEnter+mouseDown
Determine the last location of the mouse before mouseLeave+mouseDown and use that to determine scroll direction
Start a slow scroll when mouse is within a few pixels of an edge (which edge determines direction) and then scroll faster on mouseLeave+mouseDown
Somehow involve window.mouseMove (instead of canvas.mouseMove) and track it that way (which seems really ugly to me)
Something else I'm missing that will seem really obvious in retrospect
I can handle the code, I just want to figure out the best conceptual approach to take. Ideally, I'd love to handle extending the selection diagonally (scrolling right and down simultaneously, or at least alternating between the two so it appears that way), but that's not a deal breaker.
You can use .setCapture to let your canvas continue to get mouse events even when the mouse is moved outside the canvas:
https://developer.mozilla.org/en-US/docs/Web/API/Element.setCapture

Javascript - onscroll moves smoothly to next anchor? How-To?

I'm building a single-page website with a few sections that each fill out the user's window; I've got that working.
What I want to do is:
When the user scrolls up or down he/she would ease-up or down (accordingly) to the section before or after. My sections each have a anchor at the top of them.
Here is an example of what I'm trying to achieve. Each article fills the page. Once you scroll you jump to the next article.
http://www.made-my-day.com/
I think you could get the job done using this plugin: https://github.com/alvarotrigo/fullPage.js.
Also, it seems to be actively updated. The last commit to the repo was made 3 days ago.
Cheers!
You should take a look at scrollorama and superscrollorama.
They are lots of cool effects that you can use for scrolling, including the one just like the site you provided.
--UPDATE--
After some talking with OP, I realized that both libraries don't do what he wants.
So, my new suggestion is reveal-js, a js presentation library.
You don't really want to do this on an onscroll. Consider that onscroll isn't really anything except an event which says "the view of the page is moving".
That doesn't mean that they're using the mousewheel to do it.
On a phone, your plan can make sense: then it would be like making a drag movement equal to a swipe movement. Great.
My preferred method for scrolling is to click the middle-mouse button, and then position the mouse just below the anchor point, so that I can read each block of text as it scrolls past the screen.
I don't even need a hand on the mouse, for long blocks.
So in my case, onscroll will fire at something like 60 events/sec, and if you auto-jump the articles, I'm going to be teleporting through your entire site's content.
Other people still drag the actual scrollbar.
Listening to the mousewheel and keys (up/down, pg-up/pg-down), rather than just any method of moving the page, is safer... ...but are you sure all articles are going to be small enough so that all content fits in all browser windows, even at stupid-small resolutions (iPhone 3)?
Because if people need to scroll to read content, then all of a sudden you're dealing with a much, much more complex solution:
You would be required to listen to regular (or customized) scroll requests of any kind, to get to the bottom of the current content... ...and then you'd have to provide some sort of visual queue to the user that they are now at the very bottom of the content, and continuing to use a trigger method (swipe/drag/keys/mwheel) would switch articles.
The first two are fine... ...make it feel spring-loaded, like smartphones do.
...what about the other two, where people might expect to hit them multiple times in a second, to get where they're going?

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