Selection

User Interaction

In the List widget, selection is disabled by default. To enable it, choose one of selection modes using the selectionMode option.

JavaScript
$(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.

JavaScript
$(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.

JavaScript
$(function() {
    $("#listContainer").dxList({
        // ...
        selectAllMode: "allPages" // or "page"
    });
});

View Demo

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]
        });
    });
    NOTE
    To specify the key field, use the keyExpr option of the List or the key option of the Store.
  • 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(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(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(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.

JavaScript
$(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
        }
    });
});

View Demo

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.

JavaScript
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