- DataTables 1.9 had 5 different parameters that controlled how Ajax
data was obtained, which with its own naming properties, often mapping
to the jQuery.ajax methods, or otherwise extending them. To hugely
simply and extend the Ajax functionality DataTables has, these five
parameters have now been deprecated and the funtionality provided by
them merged into the new `ajax` parameter.
- Deprecated properties:
- sAjaxSource
- fnServerData
- sAjaxDataProp
- sServerMethod
- fnServerParams
- Note that these parameters are still fully supported and can be used,
but for new projects, `ajax` should be used as they will eventually be
removed (likely DataTables v2 whenever that is, as they are too widely
used to be removed in v1.x).
- Added additional / missing tests for the deprecated properties to
ensure full backwards compatiblity
- The new `ajax` property is fully documented in the doc comments, but
as a summary it can take three forms:
- string - the url to get the data from (i.e. this is the new
sAjaxSource)
- object - maps directly to jQuery.ajax, allowing full control of the
Ajax call (provides the abilities of fnServerParams, sServerMethod,
sAjaxDataProp)
- function - a function so you can get the data your own way
(provides the abilities of fnServerData)
- Added unit tests for the new `ajax` property and doc comment examples
updated to use this property exclusively.
- As of jQuery 1.8 `andSelf` was deprecated in favour of `andBack`.
`andBack` was not available in jQuery <1.8, and I don't want to make
1.8 a requirement yet, so a small workaround requiring two unbind
calls is used to avoid calling `andSelf` or `andBack`.
- jQuery migrate gives a warning about the use of `attr` rather than
`prop`. However, we should really just be using `val` here - much
easier.
- Thread: 13931
object notation.
- Previously if you had an object key that contained a period, it
wouldn't work with `data` or `render` (or rather it would need a
function call to do it manually), since a split was being done on the
periods to reconstruct the Javascript object property chain. Now it is
possible to escape a period, allowing it to be included in the
property name read / set.
- Example:
$('#example').dataTable( {
columns: [
{ data: 'a' },
{ data: 'b\\.c' }
],
data: [
{ 'a': 1, 'b.c': 2 },
{ 'a': 3, 'b.c': 4 },
{ 'a': 5, 'b.c': 6 },
{ 'a': 7, 'b.c': 8 }
]
} );
- As part of completing the planning development for reading data, I've
added support for calling functions from the string defined in `data`
and `render` column options. So you can now do something like:
`render: 'name()'` rather than needing to use an anon function and
calling name() in that. This is useful for cases where you want to
give DataTables an array of Javascript instances, rather than objects
or arrays (see example below). It also fully supports the continuation
of the dotted notation DataTables supports, so you could use
`name().first` if `name()` returns an object. Again to make it easier
than needed to define a function.
- Documentation for `data` and `render` updated to reflect this
abilities
- Unit tests for this still to come
- There is one backwards incompatiblity that should be noted - although
I think this is a real edge case and I just can't see it being an
issue. If before, you had `data:null` without `render` or
`defaultContent` specified, DataTables would have output an empty
cell. Now it will output the original data source object. Can't see
this being an issue since, why would you have a column empty cells? If
this is an issue, then you simply need to add `defaultContent:''` now.
- Example use case, using Javascript instances:
$(document).ready(function() {
var z = function (i) {
this.a = function (set) {
if ( set ) {
return this;
}
return i+'-0';
};
this.b = function (set) {
if ( set ) {
return this;
}
return i+'-1';
};
this.c = function (set) {
if ( set ) {
return this;
}
return i+'-2';
};
this.d = function (set) {
if ( set ) {
return this;
}
return i+'-3';
};
this.e = function (set) {
if ( set ) {
return this;
}
return {
q: i+'-4q',
w: i+'-4w'
};
};
};
window.dataset = [
new z(0),
new z(1),
new z(2),
new z(3),
new z(4),
new z(5)
];
$('#example').dataTable( {
columns: [
{ data: null, /*render: 'a()'*/ },
{ data: 'b()' },
{ data: 'c' },
{ data: 'd()' },
{ data: 'e().q' }
],
data: dataset
} );
} );
- Typically I think setting bDestroy or bRetrieve as default true is a
bad idea as it could lead to more processing of tables than is needed
by mistake, but if set the defaults should be acted upon.
- These are slightly different to the other defaults since the settings
object hasn't been expanded by the point they are checked, so need to
manually check the values.
- When scrolling is enabled, the scrollbar can be placed on the right or
the left of the scrolling container by the browser for rtl layout (of
the current browsers, only Safari appears to place it on the right) -
when placed on the left the padding adjustment that DataTables makes
for the scrollbar area was added to the wrong side.
- To cope with this, the browser compat method (moved to the compat
file) will check for the position of the scrollbar and set a flag so
the scroll draw can adjust the position as needed.
Removed: fnCookieCallback (cookieCallback) - This is now irrelevant since DataTables does not state save in cookies by default.
Removed: sCookiePrefix (cookiePrefix) - This is now irrelevant since DataTables does not state save in cookies by default.
Depreciated: iCookieDuration (cookieDuration) - Since DataTables does not use cookies for state saving by default the name of this parameter is now incorrect. The new parameter `stateDuration` should be used instead, although the old parameter is still supported. It will be removed in the next major version of DataTables.
Update - Performance / Memory: The functions that DataTables uses are not instance based, they are locally scoped, but they were included in the DataTable constructore, which meant that every time you create a new 'instance' of DataTables ($().dataTable()) it would create these functions in that scope again and again. That's completely pointless since we only need them once, so moving them outside the constructor helps both performance and memory (not huge, but very little helps!).
Backwards compatibility issues: The main goal here (other than to use camel-case notation!) is to preserve backwards compatibility. Unfortunately this isn't 100% possible:
- DataTable.defaults.columns has been renamed to be DataTable.defaults.column
- Otherwise it conflicts with aoColumns in the defaults.
Without doubt this is going to be a long process - for example the unit tests and examples need to be completely updated for this change. The JSDoc comments have been updated, so the site should take care of itself for the most part, when released.
In terms of implementation, it is important to note that I have not broken backwards compatibility here - the way it is does is that the current defaults are retained, and a camel-case to Hungarian mapping is automatically generated and then applied to the objects given by the end user. This adds around 0.5K to the size of DataTables, but writing the mapping manually would require at least 3K, and changing DataTables wholesale to camel-case would utterly break backwards compatibility. This is the least 'evil' way to accomplish this. It is important to note that this is a step along the roadmap for DataTables - come v2 Hungarian notation will likely be dropped completely.
One important note to make about this mapping is that if you use camel-case DataTables will copy the value from the camel-case properties to their Hungarian counterparts, so you will end up with additional properties on your source object. As I say, this appears to be to be the least 'evil' option, although still not perfect itself. The challenges of working with legacy software and installs...!
simplify conditions:
!A || (A && (B || C)
really is the same as:
!A || (true && (B || C))
which simplifies to:
!A || (B || C)
which simplifies to:
!A || B || C
- With the introduction of the -pre method in DataTables 1.9, the -asc and -desc sorting functions became more or less redundant since they are simple comparisons (all of the complexity is now in the -pre formatting function). As such the call to the -asc / -desc method is overhead that really isn't needed, and this commit introduces a sort function that doesn't call the -asc / -desc methods, instead just doing the comparison itself. In tests, this relatively simple change leads to a performance improvement of around 15% in all browsers (it also has the side benefit of less operations, so IE8- will be able to sort larger tables before flagging up a slow script warning).
- We can't just remove the sorting method which will call -asc / -desc though since not all sorting plug-ins will have a -pre method. Therefore, for backwards compatiblity the old sort function (albeit updated for the changed variables) is retained. The backwards compatibality code adds around 300 bytes to the library, but this is an unaccounced change, so backwards compatiblity must be retained.
- The old sort method will be removed in v1.11. The -asc and -desc methods are now fully depricated.
- Altered the sorting method to flatten the aaSorting array since the introduction of aDataSort in v1.9 required an extra loop in several locations. The functionality is very useful, but the extra loop can be a bit messy and slightly hit performance, so it is now flattened to be a single array (with object information so it makes sense, rather htan array indexes!).
- Altered the order of sorting when building _aSortData since it was looking up the same variable smultiple times which really wasn't needed.
This is part of a small incremental changes plan for DataTables! There are still a huge number of things to improve in this area, but this is a nice clean up and a nice 15% sorting performance improvement to get us started :-).
Note: _fnColumnOrdering is left in place at the moment, although it may be updated as work progresses on 1.10 with regard to the increased use of column names.
Removed: fnRender - fnRender was depricated in 1.9 and is now being completely removed here. Its always been a bit messy and is now superseded by mRender. The main reason for this is that DataTables use to take an independent copy of the input data source object / array. This is a performance hit and it means we can't do any binding to external objects (for example it makes Knockout integration almost impossible).
Removed: bUseRendered - with fnRender being removed, bUseRendered is irrelevent
Updated: With fnRender being removed we no longer need to take an independent copy of the data source object / array (since DataTables itself isn't ever going to write to it now - fnRender did and the copy was included so we didn't inadvertantly change a developers data source object without them knowing about it. This is no longer a problem, and in fact having it use the same data source object is extremely useful in many cases.
Simplify and improve performance
- Only check once for the presence of any sorting class instead of checking for the 3 individual classes
- Use lastIndexOf(str, 0) instead of indexOf
http://jsperf.com/rep-reg-string/4
Use greedy match regex for replacements
Otherwise, you could have:
"_START_ of _TOTAL_, showing _START_ to _END_"
replaced as:
"1 of 5, showing _START_ to 3"
Tweaks to improve performance
Cache nodes
Restructure to use nextSibling rather than childNodes
(small increase in file size, but may be a slight decrease in minified size)
Fix: Use jQuery html() and text() for HTML data to search method. Much tidier and copes with strict XHTML - downside is that it is a little slower if & is in a data string.
