On my site I have a set of input buttons with sizes.
// input elements
<input type="button" value="S" class="pblI" />
<input type="button" value="M" class="pblI" />
<input type="button" value="L" class="pblI" />
// output element
<input type="text" id="sizeMaster" value="" />
The user can click these buttons to construct an assortment, for example size S/1, M/2, L/3. A click on size S adds S/1 to the assortment. Next click on S make it S/2 and so on.
I'm using it on a mobile site with Jquery Mobile, so I know I'm getting the 300ms delay click.
Still the script is awfully slow to exectute, so I'm wondering if someone can point me to any "performance enhancements" for the following:
// an array and defaults
var remSize = [],
remIndex = -1,
szString, remData, i;
// click listener
$(document).on('click', '.pblI', function () {
// when clicked, construct a new object ala {size=S;qty=1}
szString = "";
remData = {};
remData.size = $(this).find('input').val();
remData.qty = 1;
// loop through the array to see whether the size is already in there
for (i = 0; i < remSize.length; i++) {
// return index position of size (otherwise index stays on -1)
if (remSize[i].size == remData.size) {
remIndex = i;
break;
}
}
// if the size is not in the array push the new object into the array
if (remIndex == -1 || typeof remIndex == "undefined") {
remSize.push(remData);
} else {
// else increase qty of exisiting size by 1
++remSize[remIndex].qty;
}
// create input string to display for the user
$(remSize).each(function (i) {
szString = szString + remSize[i].size + "/" + remSize[i].qty + " ";
// this will output something like this: 34/1 36/2 38/1
});
// update input field
$('#sizeMaster').val(szString);
});
I don't know what exactly is slow, but you can do these parts a little bit faster:
for (i = 0; i < remSize.length; i++) {
// return index position of size (otherwise index stays on -1)
if (remSize[i].size == remData.size) {
remIndex = i;
break;
}
}
to
for (i=0,j=remSize.length;i<j;++i) {
// return index position of size (otherwise index stays on -1)
if(remSize[i].size === remData.size) {
remIndex = i; i = j;
}
}
and
$(remSize).each(function (i) {
szString = szString + remSize[i].size + "/" + remSize[i].qty + " ";
// this will output something like this: 34/1 36/2 38/1
});
to
for(i=0;i<j;++i) {
szString += remSize[i].size + "/" + remSize[i].qty + " ";
}
and
$('#sizeMaster').val(szString);
to
document.getElementById('sizeMaster').value = szString;
But i don't think this will make a big difference.
Edit: Of course you need to define "j" at the beginning.
You can remove some of the delay by listening for touchend rather than click
Here's an example - http://code.google.com/mobile/articles/fast_buttons.html
The technical post webpages of this site follow the CC BY-SA 4.0 protocol. If you need to reprint, please indicate the site URL or the original address.Any question please contact:yoyou2525@163.com.