User Interaction
In the List widget, selection is disabled by default. To enable it, choose one of selection modes using the selectionMode option.
- $(function() {
- $("#listContainer").dxList({
- // ...
- selectionMode: "single" // or "multiple" | "all" | "none" (disables selection)
- });
- });
To select a List item, an end user simply clicks or taps it. Selected items become shaded. If you want to indicate selected items more manifestly, set the showSelectionControls option to true. This setting adds a check box to each item on the List. Also, make this setting if you use the "all" selectionMode. Otherwise, the "Select All" check box will be missing.
- $(function() {
- $("#listContainer").dxList({
- // ...
- showSelectionControls: true
- });
- });
When data in the List is paginated, you can choose whether the "Select All" check box will select all items on all pages or items on the currently rendered pages only. To make this choice, specify the selectAllMode option.
- $(function() {
- $("#listContainer").dxList({
- // ...
- selectAllMode: "allPages" // or "page"
- });
- });
See Also
API
You can select an item or cancel its selection in the following ways.
By key
Add or remove the key from the selectedItemKeys collection.JavaScript- var list = $("#listContainer").dxList("instance");
- var selectedKeys = list.option("selectedItemKeys");
- // Selects the item with key 5
- selectedKeys.push(5);
- list.option("selectedItemKeys", selectedKeys);
- // Cancels the selection of the item with key 5
- selectedKeys = $.grep(selectedKeys, function(key) {
- return key != 5;
- });
- list.option("selectedItemKeys", selectedKeys);
You can also use the selectedItemKeys collection to select items initially.
JavaScript- $(function() {
- $("#listContainer").dxList({
- // ...
- selectedItemKeys: [0, 2, 5]
- });
- });
By data object
Add or remove the data object from the selectedItems collection.JavaScript- var fruits = [
- { fruit: "Apples", count: 10 },
- { fruit: "Oranges", count: 12 },
- { fruit: "Lemons", count: 15 }
- ];
- var list = $("#listContainer").dxList("instance");
- var selectedItems = list.option("selectedItems");
- // Selects the "Oranges" item
- selectedItems.push(fruits[1]);
- list.option("selectedItems", selectedItems);
- // Cancels the selection of the "Oranges" item
- selectedItems = $.grep(selectedItems, function(item) {
- return item != fruits[1];
- });
- list.option("selectedItems", selectedItems);
You can also use the selectedItems collection to select items initially.
JavaScript- var fruits = [
- // ...
- ];
- $(function() {
- $("#listContainer").dxList({
- dataSource: fruits,
- selectedItems: [fruits[0], fruits[2]]
- });
- });
By index
Pass the index to the selectItem(itemIndex) or unselectItem(itemIndex) method. If the List is grouped, these methods should be given an object with the indexes of the group and the item.JavaScript- var list = $("#listContainer").dxList("instance");
- // Selects the item with index 1
- list.selectItem(1);
- // Checks that the item with index 1 is selected; if so, cancels the selection
- if(list.isItemSelected(1)) {
- list.unselectItem(1);
- }
- // Selects the item with index 3 in the group with index 2
- list.selectItem({ group: 2, item: 3 });
- // Checks that the item with index 3 in the group with index 2 is selected; if so, cancels the selection
- var itemToUnselect = { group: 2, item: 3 };
- if(list.isItemSelected(itemToUnselect)) {
- list.unselectItem(itemToUnselect);
- }
By DOM node
Pass the DOM node to the selectItem(itemElement) or unselectItem(itemElement) method.JavaScript- var list = $("#listContainer").dxList("instance");
- var itemNodes = $("#listContainer").find(".dx-list-item");
- // Selects the last item by its DOM node
- list.selectItem(itemNodes[itemNodes.length-1]);
- // Checks that the last item is selected; if so, cancels the selection
- if(list.isItemSelected(itemNodes[itemNodes.length-1])) {
- list.unselectItem(itemNodes[itemNodes.length-1]);
- }
See Also
Events
The List widget fires the selectionChanged event when an item is selected or when the selection is cancelled. The widget also fires the selectAllValueChanged event when the "Select All" check box has changed its value. If the functions that handle these events are not going to be changed during the lifetime of the widget, assign them to the corresponding onEventName options when you configure the widget.
- $(function () {
- $("#listContainer").dxList({
- // ...
- onSelectionChanged: function(e) {
- var addedItems = e.addedItems;
- var removedItems = e.removedItems;
- // Handler of the "selectionChanged" event
- },
- onSelectAllValueChanged: function(e) {
- var newCheckBoxValue = e.value;
- // Handler of the "selectAllValueChanged" event
- }
- });
- });
If you are going to change the event handlers at runtime, or if you need to attach several handlers to a single event, subscribe to this event using the on(eventName, eventHandler) method. This approach is more typical of jQuery.
- var selectionChangedEventHandler1 = function(e) {
- // First handler of the "selectionChanged" event
- };
- var selectionChangedEventHandler2 = function(e) {
- // Second handler of the "selectionChanged" event
- };
- $("#listContainer").dxList("instance")
- .on("selectionChanged", selectionChangedEventHandler1)
- .on("selectionChanged", selectionChangedEventHandler2);
See Also
If you have technical questions, please create a support ticket in the DevExpress Support Center.