auto repeat the up/down arrow key? - javascript

in firefox when im inside a input textbox and press down the up/down arrow key it doesn't autorepeat. how can i make that happen and control how many keypress it will fire up per sec?
UPDATE: i use:
$('#search_view #search').live('keydown', function(event) {
if(event.keyCode == 40) {
// code
}
});
but it just execute the code one time..i would like it to repeat when holding down the down-arrow.

Use .keydown() instead ..
quote from jQuery .keypress()
In addition, modifier keys (such as
Shift) cause keydown events but not
keypress events.
Arrows fall do not fall in the same category as Shift, but are treated in a special way ... the keydown will do the trick ..
Update
After your comment here is a sample that works in
FF 3.5.x and 3.0.11
IE 6, 7
Google Chrome 4.0.x
Safari 4.0.4
It only does not work on Opera (Edit: works on Opera 12.16) but it does not work with any key .. not just the arrows..
About the rate, you can not alter it from your code.. it is a system option (from BIOS and from keyboard settings in control panel -windows- )

Related

How to capture ALT+N on keypress in JavaScript

I have some simple code which logs the pressed key code, like this:
window.addEventListener('keypress', function(e) {
console.log(e.keyCode);
})
It seems to work for Alt + pretty much every other on my keyboard. Except for Alt + N.
It seems to not be registering the event at all! Just N (without the Alt) seems to work, and so do other combinations like Ctrl + N. When I type Alt + N nothing else happens, so it's not been reserved by the system as far as I know. I am using Chrome on a Mac.
Is this just something wrong with my computer or does it happen for others too? If it does happen for others, why does it do this and are there ways to detect it?
Try :
window.addEventListener('keydown', function(e) {
if (e.altKey == true && e.keyCode == 78)
console.log('Alt + N');
});
Using keypress event doesn't work for me for Alt+N and for any combination with Alt for that matter. Some combinations are working with Ctrl and some aren't.
However, when I listen for keydown and keyup events, I am able to log these events. So, I guess you could listen for keydown event on Alt and if there is a keydown event for N before Alt generates keyup, you have successfully detected a Alt+N combo.
I am not sure about why this happens though.
EDIT
According to Mozilla documentation,
The keypress event is fired when a key that produces a character value is pressed down. Examples of keys that produce a character value are alphabetic, numeric, and punctuation keys.
Examples of keys that don't produce a character value are modifier keys such as Alt, Shift, Ctrl, or Meta.
As for why some shortcuts work in Chrome, while some do not, Mozilla says
Chrome does not fire the keypress event for known keyboard shortcuts. Which keyboard shortcuts are known depends on the user's system. Use the keydown event to implement keyboard shortcuts.

How to detect pressed key on BlackBerry using JQuery Mobile?

I am using JQuery Mobile to developing my own app for BlackBerry based on WebWorks(HTML5,CSS3,JS) tecknologies.
On my layout div i have 3 input elements.
I am wont to detect BlackBerry enter key pressed in first input to focus on next input.
How i can check if hardware enter key(and other keys like "T","R","D") pressed using JQuery Mobile??
There's nothing specific to jQuery Mobile for this. You just need to add an event listener on the input and listen to the appropriate keypress event. You can find a nice explanation for them here.
Here's some sample code to get you started (not tested, you might need to debug):
$('#firstInput').keypress(function(event) {
if ( event.which === 13 ) {
$('#secondInput').focus();
}
);
In the event.which, the key code gets checked (13 is for enter). Other keys have different key codes. Be careful, I remember a bug on Blackberry that it wouldn't trigger the keypress event for backspace.
Be more specific about your problem if you need more details.

Prevent default event action not working...?

I'm trying to add keyboard shortcuts on my website to make fast navigation possible using the keyboard. I'm running into a slight problem, however, with my attempted Alt+X shortcut. The event runs just fine and returns false as it should, but the browser's File menu comes up regardless. I've also tried the preventDefault method, but no change.
The cut-down version of the script is:
document.documentElement.onkeydown = function(e) {
e = e || window.event;
switch( e.keyCode || e.which) {
// some cases here - most notably:
case 116: // F5 key
if( activeFrame) {
activeFrame.contentWindow.location.reload();
// reloads an iframe if one is active
return false;
}
break;
// more cases...
case 88: // X key
if( e.altKey) {
// do something
return false;
}
}
}
As noted above, overriding the default action of the F5 key works just fine - the browser reloads the page only if no iframe is active. I don't quite see how to prevent the menu from appearing when Alt+X is pressed.
use stopPropagation(e); instead of preventDefault method
function stopPropagation(e)
{
e = e || event;/* get IE event ( not passed ) */
e.stopPropagation? e.stopPropagation() : e.cancelBubble = true;
}
Reference link
Another SO question which mentions that preventDefault has issue in IE.
UPDATE
Try using below code as per MSDN Reference
event.returnValue=false;
And some point from Detecting keystrokes
Some general caveats:
Generally, Mac is less reliable than Windows, and some keys cannot be detected.
Explorer doesn't fire the keypress event for delete, end, enter, escape, function keys, home, insert, pageUp/Down and tab.
Onkeypress, Safari gives weird keyCode values in the 63200 range for delete, end, function keys, home and pageUp.Down. The onkeydown and -up values are normal.
Alt, Cmd, Ctrl and Shift cannot be detected on Mac, except in Opera. However, you can always use the altKey, ctrlKey, and shiftKey properties.
I actually had a web app working just fine with CTRL shortcut keys, but then decided I'd be clever and use the accesskey attribute, and ran into this exact issue with IE.
The problem with going to CTRL shortcut keys is that many of those are more standard/useful across many applications (eg: cut, copy, paste, select all).
Ctrl+Alt is fairly safe, but requires more work on the user's part.
I tend to just try to stick to ALT shortcuts IE doesn't stubbornly insist on handling.
Demo of CTRL + A/CTRL + F being cancelled successfully:
http://jsfiddle.net/egJyT/
This answer seems to imply it isn't possible to disable the menu shortcuts without putting IE into kiosk mode.
Beware that if you manage to successfully prevent the browser from detecting a key combination you may make your page unusable for some users. Many screen readers have reserved almost any key you can think of to control the screen reader and if your page was accessible using a screen reader before you added the shortcut key code, it may be completely un-accessible users needing screen readers after you add it.
Read this article about access keys (a bit old but probably still relevant), and this article about Reserved Keystroke Combinations before you invest too much time on this problem.

keycode 13 and keycode 10 not working

Event keypress 13 and 10 not working on iPhone safari, android firefox but working with android default browser.
I have a jsp page which has a form which that takes a number as input and changes values of other div elements in the same page by dividing those numbers by this input.
I am using keypress function of jQuery and testing with keycode 10 and 13 for this. It's working on all desktop browsers but the GO button doesn't fire on safari and firefox on smart phones. Please let me know how to go about this?
Here is the partial code I have used:
$('.number').keypress(function(e) {
if(e.keyCode == 10 || e.keyCode == 13 ) {
$('#1').html((textreplace/input).toFixed(0)+'g');
$('#2').html((textreplace2/input).toFixed(0)+'%');
$('#3').html((textreplace3/input).toFixed(0)+'g');
...
..
}
}
The ".number" is the class name used in the input form which has type="text". So, basically I am not using submit at all.
Try using keyup and keydown. keypress event is not really ideal.

Prototype observe event problem in Opera

I'm using Prototype and doing Event.observe on window.document.
I'm catching enter (keyCode 13) and alt+f (altKey && keyCode=70).
My code is working super with firefox, IE and chrome. With Opera no. Enter is catched, but only if my focus is not in any text input. Alt+F is not working at all.
Is it bug in Prototype or I need to do something 'extra' on Opera in order to go on? As i said, in all other browser my code works....
Firstly, the following is a helpful resource: http://unixpapa.com/js/key.html
Secondly, you should know there is a difference between keydown (or keyup) and keypress. keypress does not typically allow modifier keys, though it does allow some in Opera like control. Better to use keydown for cross-browser consistency.
I get keyCode === 13 in Opera 11.10 no matter whether the textbox is entered or not, and no matter whether using Prototype like this:
Event.observe(document, 'keydown', function (e) {
alert(e.charCode+'::'+e.keyCode);
});
or using the native method directly (using attachEvent for IE):
if (document.addEventListener) {
document.addEventListener('keydown', function (e) {
alert(e.charCode+'::'+e.keyCode);
}, false);
}
else { // IE
document.attachEvent('onkeypress', function (e) {
alert(e.charCode+'::'+e.keyCode);
});
}
However, alt is indeed not detected inside a textbox unless combined with a control or function key (though that doesn't work in Chrome or IE). This may be because Windows uses alt to give access to the applications menu bar.
You could try using control key and using preventDefault() (to avoid default behaviors like ctrl-f doing a page find) though this might annoy your users who might not want their browser behaviors disabled for your page.
Alt-F activates the menu and Opera doesn't let JavaScript handle this key press.

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