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@rosieks
Created February 4, 2014 20:58
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DataTables 1.10 binding handler for knockout
(function ($, ko) {
ko.gridModel = function (requestData) {
var page = ko.observable(1),
pageSize = ko.observable(20).extend({ throttle: 0 }),
sortField = ko.observable().extend({ throttle: 0 }),
sortOrder = ko.observable('ASC').extend({ throttle: 0 }),
totalRows = ko.observable(),
items = ko.observableArray();
var model = {
page: page,
pageSize: pageSize,
sortField: sortField,
sortOrder: sortOrder,
totalRows: totalRows,
items: items
};
_subscribe();
_requestData();
return model;
function _requestData() {
console.log('Request ' + model.pageSize() + 'rows');
requestData(model).done(function (items, totalRows) {
model.totalRows(totalRows);
model.items(items);
});
}
function _subscribe() {
var fields = ['page', 'pageSize', 'sortField', 'sortOrder'];
for (var i = 0, j = fields.length; i < j; i++) {
model[fields[i]].subscribe(_requestData);
}
}
};
ko.gridModel.inMemory = function (items) {
return ko.gridModel(function (model) {
var dfd = $.Deferred();
setTimeout(function () {
var start = parseInt(model.pageSize() * (model.page() - 1)),
end = parseInt(model.pageSize() * model.page()),
result = [];
var sortField = model.sortField();
var sortMultiplier = model.sortOrder() === 'asc' ? -1 : 1;
items.sort(function (i, j) {
if (ko.unwrap(i[sortField]) < ko.unwrap(j[sortField])) {
return sortMultiplier;
}
else if (ko.unwrap(i[sortField]) > ko.unwrap(j[sortField])) {
return -sortMultiplier;
}
else {
return 0;
}
});
for (var i = start; i < end && i < items.length; i++) {
result.push(items[i]);
}
dfd.resolve(result, items.length);
}, 0);
return dfd;
});
};
ko.dtColumn = function (name, displayName) {
var args;
if (arguments.length === 2 || arguments.length === 1 && typeof (name) === 'string') {
args = { name: name, displayName: displayName };
}
else {
args = name;
}
return {
data: propertyGetter,
render: createTemplateFn(args.template, args.name),
title: args.displayName || args.name,
sortable: !!args.name
};
function propertyGetter(source, type) {
if (type === 'display') {
return args.name || '$data';
}
else if (type === 'filter' || type === 'sort') {
return args.name;
}
else if (type === 'set') {
return;
}
else {
return function () { return source[args.name] || source; };
}
}
function createTemplateFn(value, bindingField) {
return function () {
return value || '<td data-bind="text: ' + (bindingField || '$data') + '"></td>';
};
}
};
ko.bindingHandlers.datatables = {
init: function (element, valueAccessor, allBindingsAccessor, viewModel, bindingContext) {
var binding = valueAccessor();
var options = {
columnDefs: $.each(binding.columns, function (i, val) { val.targets = [i]; }),
displayLength: binding.datasource.pageSize(),
displayStart: binding.datasource.pageSize() * (binding.datasource.page() - 1),
serverSide: true,
dom: buildDom(binding),
deferRender: binding.deferRender || binding.virtualScrolling,
scrollY: setupHeight(binding)
};
createRowTemplate(options.columnDefs);
options.serverData = function (source, data) {
var start = data.start,
pageSize = data.length,
page = start / pageSize + 1,
sortField = binding.columns[data.order[0].column].data(undefined, 'sort'),
sortOrder = data.order[0].dir;
binding.datasource.page(page);
binding.datasource.pageSize(pageSize);
binding.datasource.sortField(sortField);
binding.datasource.sortOrder(sortOrder);
};
options.rowCallback = function (row, srcData, displayIndex) {
var itemContext = bindingContext.createChildContext(ko.unwrap(srcData), options['as']);
itemContext['$index'] = ko.observable(displayIndex);
ko.renderTemplate(binding.rowTemplate || element, itemContext, {}, row, 'replaceChildren');
if (binding.rowCallback) {
binding.rowCallback(row, srcData);
}
if (ko.isObservable(binding.selectedRow)) {
$(row).click(function () {
binding.selectedRow(srcData);
});
}
return row;
};
$(element).dataTable(options);
binding.datasource.items.subscribe(function (newItems) {
var dataTable = $(element).dataTable();
var api = dataTable.api();
var tableNodes = api.rows().nodes();
if (tableNodes.length) {
// Unregister each of the table rows from knockout.
ko.utils.arrayForEach(tableNodes, function (node) { ko.cleanNode(node); });
}
dataTable._fnAjaxUpdateDraw({
aaData: newItems,
iTotalRecords: binding.datasource.totalRows(),
iTotalDisplayRecords: binding.datasource.totalRows()
});
});
function createRowTemplate(columns) {
var row = $('<tr>');
ko.utils.arrayForEach(columns, function (column) {
row.append(column.render());
});
var templateNodes = row[0].childNodes,
container = ko.utils.moveCleanedNodesToContainerElement(templateNodes);
new ko.templateSources.anonymousTemplate(element).nodes(container);
}
function buildDom(binding) {
if (binding.dom) {
return binding.dom;
}
return (binding.allowColumnReorder === true ? 'R' : '') + 'ti' + (binding.virtualScrolling === true ? 'S' : 'p');
}
function setupHeight(binding) {
if (binding.scrollY) {
if (typeof binding.scrollY === 'function') {
var setScrollY = function () {
var body = $(element).parent();
if (body.length > 0) {
body.height($.proxy(binding.scrollY, body)());
}
};
$(window).resize(setScrollY);
setTimeout(function () {
$(element).dataTable()._fnAdjustColumnSizing(true);
setScrollY();
}, 100);
try {
return binding.scrollY() || 500;
}
catch (err) {
return 500;
}
}
else {
return binding.scrollY;
}
}
}
}
};
})(window.$, window.ko);
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ghost commented May 18, 2015

How should we use it then?

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