我正在实现一个自定义解决方案，它将使用查询字符串参数将过滤器应用于网格来初始化kendoGrid（及其多选列）。我正在使用Kendo UI v2014.2.903和multiselectbox用户扩展。
为了实现这一点，我有一个custom JavaScript function，它将查询字符串参数解析为filter对象，并使用其filter方法将其应用于kendoGrid的dataSource属性。以下代码段：
var preFilterQueryString = getPreFilterQuery(queryString);
if (preFilterQueryString != '') {
kendoGrid.dataSource.filter(parseFilterString(preFilterQueryString));
}
我正在按如下方式初始化multiselectbox：
args.element.kendoMultiSelectBox({
dataSource: getAutoCompleteDataSource(column.field),
valuePrimitive: true,
selectionChanged: function (e) {
//ignored for brevity
}
});
我的问题是如果我使用上述方法将过滤器设置为multiselectbox，它们不会正确应用于数据集。
例如，如果我将单个过滤器作为＆＃34; Vancouver＆＃34;，则会显示正确的结果集。多选框中的选择是＆＃34;全部＆＃34;和＃34;温哥华＆＃34;。但是，在多选框中不检查温哥华的选择。这是设计的吗？请看下面的图片。
如果我通过两个过滤器温哥华和华沙，只有最后一个过滤器华沙应用于网格，并且显示仅包含华沙的数据集。同样，在multiselectbox中没有选中任何选项。
以下是应用于dataSource.filter（）方法的过滤器对象。
kendoGrid's filter object image
疑难解答
以下是multiselectbox列的selectionchanged事件处理程序的压缩版本（为简洁起见）。
if (e.newValue && e.newValue.length) {
var newValue = e.newValue;
console.log('e.newValue: ' + e.newValue);
filter.filters = [];
for (var i = 0, l = newValue.length; i < l; i++) {
filter.filters.push({field: field,operator: 'contains',value: newValue[i]});
}
kendoGrid.dataSource.filter(allFilters);
}
我注意到，当两个过滤器通过时，e.newValue是＆＃34;华沙＆＃34;而不是阵列 - ＆＃34; [温哥华，华沙]＆＃34;
我花了很多时间来解决为什么只有华沙应用于数据集。 这是我发现的：
_raiseSelectionChanged函数是引发选择更改事件的内容。在该函数中，我注意到它设置了newValue和oldValue事件参数。要设置newValue，它使用＆＃34; Value＆＃34;功能。值函数使用以下代码检索所有选定的列表项并返回它们。
else {
var selecteditems = this._getSelectedListItems();
return $.map(selecteditems, function (item) {
var obj = $(item).children("span").first();
return obj.attr("data-value");
}).join();
}
_getSelectedListItems函数使用jQuery过滤器来获取所有具有css类的列表项＆＃34; .selected＆＃34;
_getSelectedListItems: function () {
return this._getAllValueListItems().filter("." + SELECTED);
},
有一个_select事件似乎正在添加＆＃34;。选择＆＃34;用于列出项目的类。当我在第286行放置一个断点时，它只打了一次，这就是华沙。我无法理解为什么它不会被称为温哥华。我没有线索，想知道是否有人有指针。
debug capture of _select function
以下是kendoMultiSelectBox用户扩展供您参考：
//MultiSelect - A user extension of KendoUI DropDownList widget.
(function ($) {
// shorten references to variables
var kendo = window.kendo,
ui = kendo.ui,
DropDownList = ui.DropDownList,
keys = kendo.keys,
SELECT = "select",
SELECTIONCHANGED = "selectionChanged",
SELECTED = "k-state-selected",
HIGHLIGHTED = "k-state-active",
CHECKBOX = "custom-multiselect-check-item",
SELECTALLITEM = "custom-multiselect-selectAll-item",
MULTISELECTPOPUP = "custom-multiselect-popup",
EMPTYSELECTION = "custom-multiselect-summary-empty";
var lineTemplate = '<input type="checkbox" name="#= {1} #" value="#= {0} #" class="' + CHECKBOX + '" />' +
'<span data-value="#= {0} #">#= {1} #</span>';
var MultiSelectBox = DropDownList.extend({
init: function (element, options) {
options.template = kendo.template(kendo.format(lineTemplate, options.dataValueField || 'data', options.dataTextField || 'data'));
// base call to widget initialization
DropDownList.fn.init.call(this, element, options);
var button = $('<input type="button" value="OK" style="float: right; padding: 3px; margin: 5px; cursor: pointer;" />');
button.on('click', $.proxy(this.close, this));
var popup = $(this.popup.element);
popup.append(button);
},
options: {
name: "MultiSelectBox",
index: -1,
showSelectAll: true,
preSummaryCount: 1, // number of items to show before summarising
emptySelectionLabel: '', // what to show when no items are selected
selectionChanged: null // provide callback to invoke when selection has changed
},
events: [
SELECTIONCHANGED
],
refresh: function () {
// base call
DropDownList.fn.refresh.call(this);
this._updateSummary();
$(this.popup.element).addClass(MULTISELECTPOPUP);
},
current: function (candidate) {
return this._current;
},
open: function () {
var self = this;
this._removeSelectAllItem();
this._addSelectAllItem();
if ($(this.ul).find('li').length > 6) {
$(this.popup.element).css({ 'padding-bottom': '30px' });
}
else {
$(this.popup.element).css({ 'padding-bottom': '0' });
}
DropDownList.fn.open.call(this);
//hook on to popup event because dropdown close does not
//fire consistently when user clicks on some other elements
//like a dataviz chart graphic
this.popup.one('close', $.proxy(this._onPopupClosed, this));
},
_onPopupClosed: function () {
this._removeSelectAllItem();
this._current = null;
this._raiseSelectionChanged();
},
_raiseSelectionChanged: function () {
var currentValue = this.value();
var currentValues = $.map((currentValue.length > 0 ? currentValue.split(",") : []).sort(), function (item) { return item.toString(); });
var oldValues = $.map((this._oldValue || []).sort(), function (item) { return item ? item.toString() : ''; });
// store for next pass
this._oldValue = $.map(currentValues, function (item) { return item.toString(); });
var changedArgs = { newValue: currentValues, oldValue: oldValues };
if (oldValues) {
var hasChanged = ($(oldValues).not(currentValues).length == 0 && $(currentValues).not(oldValues).length == 0) !== true;
if (hasChanged) {
//if (this.options.selectionChanged)
// this.options.selectionChanged(changedArgs);
this.trigger(SELECTIONCHANGED, changedArgs);
}
}
else if (currentValue.length > 0) {
//if (this.options.selectionChanged)
// this.options.selectionChanged(changedArgs);
this.trigger(SELECTIONCHANGED, changedArgs);
}
},
_addSelectAllItem: function () {
if (!this.options.showSelectAll) return;
var firstListItem = this.ul.children('li:first');
if (firstListItem.length > 0) {
this.selectAllListItem = $('<li tabindex="-1" role="option" unselectable="on" class="k-item ' + SELECTALLITEM + '"></li>').insertBefore(firstListItem);
// fake a data object to use for the template binding below
var selectAllData = {};
selectAllData[this.options.dataValueField || 'data'] = '*';
selectAllData[this.options.dataTextField || 'data'] = 'All';
this.selectAllListItem.html(this.options.template(selectAllData));
this._updateSelectAllItem();
this._makeUnselectable(); // required for IE8
}
},
_removeSelectAllItem: function () {
if (this.selectAllListItem) {
this.selectAllListItem.remove();
}
this.selectAllListItem = null;
},
_focus: function (li) {
if (this.popup.visible() && li && this.trigger(SELECT, { item: li })) {
this.close();
return;
}
this.select(li);
},
_keydown: function (e) {
// currently ignore Home and End keys
// can be added later
if (e.keyCode == kendo.keys.HOME ||
e.keyCode == kendo.keys.END) {
e.preventDefault();
return;
}
DropDownList.fn._keydown.call(this, e);
},
_keypress: function (e) {
// disable existing function
},
_move: function (e) {
var that = this,
key = e.keyCode,
ul = that.ul[0],
down = key === keys.DOWN,
pressed;
if (key === keys.UP || down) {
if (down) {
if (!that.popup.visible()) {
that.toggle(down);
}
if (!that._current) {
that._current = ul.firstChild;
} else {
that._current = ($(that._current)[0].nextSibling || that._current);
}
} else {
//up
// only if anything is highlighted
if (that._current) {
that._current = ($(that._current)[0].previousSibling || ul.firstChild);
}
}
if (that._current) {
that._scroll(that._current);
}
that._highlightCurrent();
e.preventDefault();
pressed = true;
} else {
pressed = DropDownList.fn._move.call(this, e);
}
return pressed;
},
selectAll: function () {
var unselectedItems = this._getUnselectedListItems();
this._selectItems(unselectedItems);
// todo: raise custom event
},
unselectAll: function () {
var selectedItems = this._getSelectedListItems();
this._selectItems(selectedItems); // will invert the selection
// todo: raise custom event
},
_selectItems: function (listItems) {
var that = this;
$.each(listItems, function (i, item) {
var idx = ui.List.inArray(item, that.ul[0]);
that.select(idx); // select OR unselect
});
},
_selectItem: function () {
// method override to prevent default selection of first item, done by normal dropdown
var that = this,
options = that.options,
useOptionIndex,
value;
useOptionIndex = that._isSelect && !that._initial && !options.value && options.index && !that._bound;
if (!useOptionIndex) {
value = that._selectedValue || options.value || that._accessor();
}
if (value) {
that.value(value);
} else if (that._bound === undefined) {
that.select(options.index);
}
},
_select: function (li) {
var that = this,
value,
text,
idx;
li = that._get(li);
if (li && li[0]) {
idx = ui.List.inArray(li[0], that.ul[0]);
if (idx > -1) {
if (li.hasClass(SELECTED)) {
li.removeClass(SELECTED);
that._uncheckItem(li);
if (this.selectAllListItem && li[0] === this.selectAllListItem[0]) {
this.unselectAll();
}
} else {
li.addClass(SELECTED);
that._checkItem(li);
if (this.selectAllListItem && li[0] === this.selectAllListItem[0]) {
this.selectAll();
}
}
if (this._open) {
that._current(li);
that._highlightCurrent();
}
var selecteditems = this._getSelectedListItems();
value = [];
text = [];
$.each(selecteditems, function (indx, item) {
var obj = $(item).children("span").first();
value.push(obj.attr("data-value"));
text.push(obj.text());
});
that._updateSummary(text);
that._updateSelectAllItem();
that._accessor(value, idx);
// todo: raise change event (add support for selectedIndex) if required
that._raiseSelectionChanged();
}
}
},
_getAllValueListItems: function () {
if (this.selectAllListItem) {
return this.ul.children("li").not(this.selectAllListItem[0]);
} else {
return this.ul.children("li");
}
},
_getSelectedListItems: function () {
return this._getAllValueListItems().filter("." + SELECTED);
},
_getUnselectedListItems: function () {
return this._getAllValueListItems().filter(":not(." + SELECTED + ")");
},
_getSelectedItemsText: function () {
var text = [];
var selecteditems = this._getSelectedListItems();
$.each(selecteditems, function (indx, item) {
var obj = $(item).children("span").first();
text.push(obj.text());
});
return text;
},
_updateSelectAllItem: function () {
if (!this.selectAllListItem) return;
// are all items selected?
if (this._getAllValueListItems().length == this._getSelectedListItems().length) {
this._checkItem(this.selectAllListItem);
this.selectAllListItem.addClass(SELECTED);
}
else {
this._uncheckItem(this.selectAllListItem);
this.selectAllListItem.removeClass(SELECTED);
}
},
_updateSummary: function (itemsText) {
if (!itemsText) {
itemsText = this._getSelectedItemsText();
}
if (itemsText.length == 0) {
this._inputWrapper.addClass(EMPTYSELECTION);
this.text(this.options.emptySelectionLabel);
return;
} else {
this._inputWrapper.removeClass(EMPTYSELECTION);
}
if (itemsText.length <= this.options.preSummaryCount) {
this._textAccessor(itemsText.join(", "));
}
else {
this._textAccessor(itemsText.length + ' selected');
}
},
_checkItem: function (itemContainer) {
if (!itemContainer) return;
itemContainer.children("input").prop("checked", true);
},
_uncheckItem: function (itemContainer) {
if (!itemContainer) return;
itemContainer.children("input").removeAttr("checked");
},
_isItemChecked: function (itemContainer) {
return itemContainer.children("input:checked").length > 0;
},
value: function (value) {
if(value != undefined)
console.log("value", value);
var that = this,
idx,
valuesList = [];
if (value !== undefined) {
if (!$.isArray(value)) {
valuesList.push(value);
this._oldValue = valuesList; // to allow for selectionChanged event
}
else {
valuesList = value;
this._oldValue = value; // to allow for selectionChanged event
}
// clear all selections first
$(that.ul[0]).children("li").removeClass(SELECTED);
$("input", that.ul[0]).removeAttr("checked");
$.each(valuesList, function (indx, item) {
var hasValue;
if (item !== null) {
item = item.toString();
}
that._selectedValue = item;
hasValue = value || (that.options.optionLabel && !that.element[0].disabled && value === "");
if (hasValue && that._fetchItems(value)) {
return;
}
idx = that._index(item);
if (idx > -1) {
that.select(
that.options.showSelectAll ? idx + 1 : idx
);
}
});
that._updateSummary();
}
else {
var selecteditems = this._getSelectedListItems();
return $.map(selecteditems, function (item) {
var obj = $(item).children("span").first();
return obj.attr("data-value");
}).join();
}
},
});
ui.plugin(MultiSelectBox);
})(jQuery);
更新
我遇到了multiselectbox的select事件的文档，该事件明确指出在以编程方式选择项目时不会触发select事件。它与我想要做的有关吗？但是，即使我以编程方式设置它们，为什么还要为其中一个过滤器触发？