jquery mobile - keyup keydown on mobile devices - javascript

I have a need for an input (type='text') to go send results to the my server to check availability of something typed by the user.
I use the delegate to add the event handlers to the elements:
$(document).delegate('#signup', 'pageshow', function() {
var keydown = function(e) {
e = e || window.event;
var char = e.which || e.keyCode;
if (char == 8) {
$(".pagemessage").text("Pressed: '<BACKSPACE>'");
appcheckDomainOnKeyDown();
}
return true;
};
var keyup = function(e) {
e = e || window.event;
var char = e.which || e.keyCode;
if (char == 8) {
appcheckDomainOnKeyUp();
}
return true;
};
var keypress = function(e) {
e = e || window.event;
var char = e.which || e.keyCode;
var str = String.fromCharCode(char);
$(".pagemessage").text("Pressed: '" + str +"'");
if (/[a-zA-Z0-9-\._]/.test(str) || char == 8 || char == 9) {
appcheckDomainOnKeyDown();
appcheckDomainOnKeyUp();
return true;
}
return false;
};
The key handers work perfectly on my desktop but not on a mobile device. Hopefully you can see that I'm trying to allow certain characters into the box (and a backspace to delete the characters.
From the fact I cannot see the pagemessage element update, 'keypress' does not seem to be trapped. I tried handling this in the keyup/keydown, but I'm not sure how to apply the shiftKey bits to get an actual character pressed - for example pressing + 5 would give '%' however in the keydown it returns shiftKey and 5.
I read the documentation and the closest I could find to 'keypress' was a 'tap' event, but that didn't work either.
I have tried trapping the 'keypress' event as suggested in one post here, and on a desktop this does not trap the backspace, and does nothing at all on a mobile device.
I then tried this as suggested in another post:
var inputEV = 'oninput' in window ? 'input' : 'keyup';
$("#new_domain").off(inputEV);
$("#new_domain").on(inputEV, function (e) {
keydown(e);
keyup(e);
});
and it does not work in either desktop browser or mobile device.
I then tried changing the input type to 'search', and I get a pretty enhancement, that a keypress does add a clear button... but does nothing on the mobile device regarding my own functionality.
I think I have run out of things to try, the only thing left is to add a button to go check - and no one wants that :)
Anyone know how I can do what I need?
In case it's relevant, I'm using chrome on my desktop and android device (HTC one, and Nexus 5)

Keyup should work. It works in this example: http://jsbin.com/aNEBIKA/2/. That tested find on my Galaxy S3. Each keypress updates the footer h3 element with the text entered.
Could it be that you are binding your listeners at the wrong time? The documentation does suggest binding like this:
$(document).bind('pageinit')
http://demos.jquerymobile.com/1.2.0/docs/api/events.html

Related

How can I disable text selection using shift without disabling all text selection?

So I know this sounds like a duplicate, but it isn't (or if it is, the accepted answer on all the ones I can find doesn't work the way I need it to). The issue is this:
I'm writing in HTML5 using jQuery, I need to make a grid allow multi-select with control and shift. I have that logic working, but whenever you shift-click it selects the text in the grid. I want to prevent this selection, but here's the critical difference between this and the other questions I found: I want selection of text to work at all other times.
To restate: I want to disable text selection using shift WITHOUT disabling all text selection for the elements specified. Does anyone know how I can do that?
-- EDIT --
The following (in the constructor for the grid) solved this for me. As the answerer suggested, I declared a class for unselectability.
this.gridBody = $("#userGrid");
var handleKeydown = function(e)
{
e = e || window.event;
var keyPressed = e.keyCode || e.which;
if (keyPressed == keys.shift) {
e.data.gridBody.addClass("unselectable");
}
};
var handleKeyup = function(e)
{
e = e || window.event;
var keyPressed = e.keyCode || e.which;
if (keyPressed == keys.shift) {
e.data.gridBody.removeClass("unselectable");
}
};
$(document).on('keydown', this, handleKeydown);
$(document).on('keyup', this, handleKeyup);
That will bind on document an event where it disables text selection upon pressing DOWN shift
document.onkeydown = function(e) {
var keyPressed = e.keyCode;
if (keyPressed == 16) { //thats the keycode for shift
$('html').css({'-moz-user-select':'-moz-none',
'-moz-user-select':'none',
'-o-user-select':'none',
'-khtml-user-select':'none',
'-webkit-user-select':'none',
'-ms-user-select':'none',
'user-select':'none'
}); //or you could pass these css rules into a class and add that class to html instead
document.onkeyup = function() {
//here you remove css rules that disable text selection
}
}
}
Hopefully i have helped you.
Based on comments
document.onkeydown = function(e) {
var keyPressed = e.keyCode;
if (keyPressed == 16) { //thats the keycode for shift
$('html').addClass('unselectable'); //unselectable contains aforementioned css rules
document.onkeyup = function() {
$('html').removeClass('unselectable'); //and simply remove unselectable class making text selection availabe
}
}
}
Another solution you might consider: instead of preventing text selection by watching for shift keys and toggling selectability, you could just clear the text selection.
window.getSelection().removeAllRanges();
I find this more convenient because it can be run in your click handler to "cancel" the default behavior. Appears to work in IE 9+ and other modern browsers.

mousemove and cross-browser e.which

I need to know which mouse key is pressed on every mousemove event, and I try to use this:
getMouseCode: function(e) {
e = e || window.event;
if (!e.which && e.button) {
if (e.button & 1) e.which = 1;
else if (e.button & 4) e.which = 2;
else if (e.button & 2) e.which = 3;
};
return e.which;
},
But this is works only in chrome and IE7-8. IE9 debugger always says e.button == 0 and e.which == 1. After some debugging I figured out that window.event for IE9 contains right value of which, so I swapped
e = window.event || e;
This also does the trick for Safari & Air, but Firefox has window.event undefined, and Opera has the same wrong values in both callback argument and window.event objects.
I was looking at this question when investigating a related issue. It turned out that my issue was that I needed to use separate functions to handle onclick and onmouseover events.
I have found that when using Opera, Safari and FireFox, the "which" property of the mousemove event object is set to 1 when no mouse button has been clicked.
Though this answer may be kind of late, I am sure it will help those in the future. I stumbled upon this question while searching for this cross browser feature and originally disregarded it. I am back to provide my answer for those that follow in my footsteps.
First, some knowledge. I found this site very helpful, as all the cross browser issues (well most) are worked out, and laid out for your amusement (I laugh when us developers need to create charts and diagrams to how browsers work..)
http://unixpapa.com/js/mouse.html
On this page, near the bottom, you will find a blue link that says "Click here with various mouse buttons to test", above this you will see a code snippet. This goes into your mousedown or mouseup. If you right click and view the source at this location, you will find a script tag that holds 2 functions, the one above this link, and a 'dont' function that prevents the events from doing their default, or falling through, though not needed in all cases, is useful to know about.
The second piece of knowledge comes from another website, and provides us some insight into how to capture the mouse wheel up and down events.
http://www.javascriptkit.com/javatutors/onmousewheel.shtml
To put this all together in 1 place, we basically have the following..
function GetMouseButton(e) {
// Normalize event variable
var e = window.event || e;
// Set button to initially not recognized (or false if you need to to be)
var button = 'Not Recognized';
// Check if this is a button push event
if(e.type == 'mousedown' || e.type == 'mouseup') {
if (e.which == null) {
// Check if IE, if so, what e.button was pressed
button = (e.button < 2) ? "Left" :
((e.button == 4) ? "Middle" : "Right");
} else {
// All other browsers, what e.which was pressed
button = (e.which < 2) ? "Left" :
((e.which == 2) ? "Middle" : "Right");
}
} else {
// If this is not a button push event, then we get the direction
var direction = e.detail ? e.detail * (-120) : e.wheelDelta;
// And name the direction as a 'button'
switch(direction) {
case 120: // Browsers use different variants of these
case 240:
case 360:
button = "Middle Scroll Up";
break;
case -120:
case -240:
case -360:
button = "Middle Scroll Down";
break;
}
}
alert(button);
}
/* Simple Bind function (like jQuery's for example) */
function Bind(elem, type, eventHandle) {
if (elem == null || elem == undefined) return;
if ( elem.addEventListener ) {
elem.addEventListener( type, eventHandle, false );
} else if ( elem.attachEvent ) {
elem.attachEvent( "on" + type, eventHandle );
} else {
elem["on"+type]=eventHandle;
}
}
/* Bind your mousedown / mouseup to the window, as well as the mousewheel */
Bind(window, 'mousedown', GetMouseButton);
Bind(window, 'mouseup', GetMouseButton);
/* One of FireFox's browser versions doesn't recognize mousewheel,
* we account for that in this line
*/
var MouseWheelEvent =
(/Firefox/i.test(navigator.userAgent))? "DOMMouseScroll" : "mousewheel";
Bind(window, MouseWheelEvent, GetMouseButton);
To save you some time [and knowledge, if you don't care to look at these links], you can view a working example at the following jsfiddle:
http://jsfiddle.net/BNefn/
EDIT
I should have also said, that since you need to know this on every mousemove event, you can simply store the resulting button 'name' and event type (down or up), and then recall that variables information during your mousemove event. If you have a variable for each of these "buttons" you can then see which button is pressed and which isn't, and clear the variables that are pressed on mouseup.

Remove Any Spaces While Typing into a Textbox on a Web Page Part II

This involves HTML + JS and/or JQuery:
I would have commented on the previous post, but I don't have comment reputation or cannot comment for some reason.
Josh Stodola's great code from Part I is as follows:
$(function() {
var txt = $("#myTextbox");
var func = function() {
txt.val(txt.val().replace(/\s/g, ''));
}
txt.keyup(func).blur(func);
});
This works great except .replace puts the cursor at the end of the string on every keyup (at least in IE8 and Chrome).
As a result, it renders the left & right cursor keys useless, which is needed inside the input box.
Is there any way to enhance the above code so that the cursor keys do not activate it, but so that the text still gets updated on the fly?
The best solution is to avoid using key events to capture text input. They're not the best tool for the job. Instead, you should use the HTML5 oninput event (supported in the latest and recent versions of every current major browser) and fall back to onpropertychange for older versions of Internet Explorer:
var alreadyHandled;
txt.bind("input propertychange", function (evt) {
// return if the value hasn't changed or we've already handled oninput
if (evt.type == "propertychange" && (window.event.propertyName != "value"
|| alreadyHandled)) {
alreadyHandled = false;
return;
}
alreadyHandled = true;
// Your code here
});
These events don't fire for keys that don't result in text entry — don't you just hate it when you shift-tab back to a form element and the resulting keyup event causes the page's script to move focus forward again?
Additional benefits over key events:
They fire immediately when the key is pressed and not when the key is lifted, as in keyup. This means you don't get a visual delay before any adjustments to the text are made.
They capture other forms of text input like dragging & droppping, spell checker corrections and cut/pasting.
Further reading at Effectively detecting user input in JavaScript.
Update the function:
var func = function(e) {
if(e.keyCode !== 37 && e.keyCode !== 38 && e.keyCode !== 39 && e.keyCode !== 40){
txt.val(txt.val().replace(/\s/g, ''));
}
}
try:
$(function() {
var txt = $("#myTextbox");
var func = function(e) {
if(e.keyCode != "37" && e.keyCode != "38" && e.keyCode != "39" && e.keyCode != "40"){
txt.val(txt.val().replace(/\s/g, ''));
}
}
txt.keyup(func).blur(func);
});
$(function() {
var txt = $("#myTextbox");
var func = function() {
txt.val(txt.val().replace(/\s/g, ''));
}
txt.keyup(function(evt){
if(evt.keyCode < 37 || evt.keyCode > 40) {
func;
}
}).blur(func);
});
Something like that should do it. It will run the function if the keycode isn't 37,38,39 or 40 (the four arrow key keycodes). Note that it won't actually stop the cursor position moving to the end when any other key is pressed. For that, you'd need to keep track of the current cursor position. Take a look at this link for jCaret plugin, which can do this

How can I disabling backspace key press on all browsers?

I'm trying to disable the backspace button on an order page in all cases except when a textarea or text input is an active element to prevent users from accidentally backing out of an order. I have it working fine in most browsers, but in IE (testing in IE9, both regular and compatibility mode) it still allows the user to hit the backspace and go to the previous page.
Here's the code:
$(document).keypress(function(e){
var activeNodeName=document.activeElement.nodeName;
var activeElType=document.activeElement.type;
if (e.keyCode==8 && activeNodeName != 'INPUT' && activeNodeName != 'TEXTAREA'){
return false;
} else {
if (e.keyCode==8 && activeNodeName=='INPUT' && activeElType != 'TEXT' && activeElType != 'text'){
return false;
}
}
});
Any advice on what I'm doing wrong here?
Thanks!
I think you're overcomplicating that. Rather than checking for an active element, find the event target instead. This should give you the information you need. It's also better to use keydown rather than keypress when there is no visible character. Finally, it's better to use e.preventDefault() for better granularity.
$(document).keydown(function(e) {
var nodeName = e.target.nodeName.toLowerCase();
if (e.which === 8) {
if ((nodeName === 'input' && e.target.type === 'text') ||
nodeName === 'textarea') {
// do nothing
} else {
e.preventDefault();
}
}
});
NB I could have done this the other way round, rather than an empty if block and all the code going in the else block, but I think this is more readable.
Instead of keypress, try the keydown function, it will fire before the actual browser based hook. Also, putting in a preventDefault() function will assist in this. IE :
$(document).keydown(function(e){
e.preventDefault();
alert(e.keyCode);
});
Hope this helps.
The most Simple thing you can do is add the following one line in the very first script of you page at very first line
window.history.forward(1);
Most examples seem to be for the JQuery framework - Here an example for ExtJS
(I've been getting a lot of downvotes for this recently as the question now has JQuery tag on it, which it didn't previously. I can remove the answer if you like as isn't for JQuery but it's proven to help others not using that framework).
To use this add this code block to your code base, I recommend adding it inside the applications init function().
/**
* This disables the backspace key in all browsers by listening for it on the keydown press and completely
* preventing any actions if it is not which the event fired from is one of the extjs nodes that it should affect
*/
Ext.EventManager.on(window, 'keydown', function(e, t) {
var nodeName = e.target.nodeName.toLowerCase();
if (e.getKey() == e.BACKSPACE) {
if ((nodeName === 'input' && e.target.type === 'text') ||
nodeName === 'textarea') {
// do nothing
} else {
e.preventDefault();
}
}
});
Use e.which instead of e.keyCode; jQuery normalizes this value across browsers.
http://api.jquery.com/keydown/
To determine which key was pressed,
examine the event object that is
passed to the handler function. While
browsers use differing properties to
store this information, jQuery
normalizes the .which property so you
can reliably use it to retrieve the
key code.
Then, use e.preventDefault(); to prevent the default behaviour of moving to the previous page.
<html>
<head>
<script type="text/javascript">
function stopKey(evt) {
var evt = (evt) ? evt : ((event) ? event : null);
var node = (evt.target) ? evt.target : ((evt.srcElement) ? evt.srcElement : null);
if ((evt.keyCode == 8) && (node.type!="text")) {return false;}
}
document.onkeypress = stopKey;
</script>
</head>
<body onkeydown="return stopKey()">
<form>
<input type="TEXTAREA" name="var1" >
<input type="TEXT" name="var2" >
</form>
</body>
</html
I had to add the onDownKey attribute to the body in order to get editing keys to go to the functions.
$(document).keydown(function(e) {
var elid = $(document.activeElement).is('input');
if (e.keyCode === 8 && !elid) {
return false;
}
});
Hope this might help you
Seems like the "backspace" will also act as "navigation back" if you have selected radio buttons, check-boxes and body of document as well. Really annoying for forms - especially when using post. All the form could be lost with one slip of the "backspace" key -_- ...
Honestly... who's idea was it to allow the "backspace as a navigational "back" button!!! really bad idea in my opinion.
I disable the "backspace" default on anything that is not a text area or text field - like this:
$(document).keydown(function(e){
console.log(e.keyCode+"\n");
var typeName = e.target.type;//typeName should end up being things like 'text', 'textarea', 'radio', 'undefined' etc.
console.log(typeName+"\n");
// Prevent Backspace as navigation backbutton
if(e.keyCode == 8 && typeName != "text" && typeName != "textarea"){
console.log("Prevent Backbutton as Navigation Back"+typeName+"\n");
e.preventDefault();
}
//
})
Not sure where else one would want the normal behavior of a back-button other than in these two areas.
document.onkeydown = KeyPress;
function KeyPress(e) {
if (!e.metaKey){
e.preventDefault();
}
}

Combination of Keypresses using JS / jQuery ( Escape & Shift +Escape )

Is there a way in js/jQuery how to have these two combinations of keypresses?
ESCape key
and
SHIFT + ESCape key
when I implemented it using:
document.onkeydown = function(e){if (e == null) {keycode = event.keyCode;}
else {keycode = e.which;}
if(keycode == 27){closeAll();}}
//upon pressing shift + esc
$(document).bind('keypress',function(event)
{
if(event.which === 27 && event.shiftKey)
{
closetogether();
}
});
The escape button works perfectly but the one with the shift + esc is getting confused I think because it's doing nothing. Don't worry the function works as when I change the combining key 27 to 90 (z) for example it works just fine.
Can someone opt me for a better way ?
Why don't you bind the keydown event using jQuery? That way you would already have a normalized event variable. You can also check the status of the shift key in the same handler.
These events send different keycodes back. Use keyup/keydown for capturing certain keys by scancodes and use keypress to capture actual text input by characters.
$(document).bind('keydown', function(event) {
if(event.which === 27){
if(event.shiftKey){
closetogether();
} else {
closeAll();
}
}
});

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