list QML Basic Type
The list
type refers to a list of QML objects.
A list value can be accessed in a similar way to a JavaScript array:
- Values are assigned using the
[]
square bracket syntax with comma-separated values - The
length
property provides the number of items in the list - Values in the list are accessed using the
[index]
syntax
Values can be dynamically added to the list by using the push
method, as if it were a JavaScript Array
A list
can only store QML objects, and cannot contain any basic type values. (To store basic types within a list, use the var type instead.)
When integrating with C++, note that any QQmlListProperty value passed into QML from C++ is automatically converted into a list
value, and vice-versa.
Using the list Type
For example, the Item type has a states list-type property that can be assigned to and used as follows:
import QtQuick 2.0 Item { width: 100; height: 100 states: [ State { name: "activated" }, State { name: "deactivated" } ] Component.onCompleted: { console.log("Name of first state:", states[0].name) for (var i = 0; i < states.length; i++) console.log("state", i, states[i].name) } }
The defined State objects will be added to the states
list in the order in which they are defined.
If the list only contains one object, the square brackets may be omitted:
import QtQuick 2.0 Item { width: 100; height: 100 states: State { name: "activated" } }
Note that objects cannot be individually added to or removed from the list once created; to modify the contents of a list, it must be reassigned to a new list.
Note: The list
type is not recommended as a type for custom properties. The var
type should be used instead for this purpose as lists stored by the var
type can be manipulated with greater flexibility from within QML.
This basic type is provided by the QML language.
See also QML Basic Types.
© The Qt Company Ltd
Licensed under the GNU Free Documentation License, Version 1.3.
https://doc.qt.io/qt-5.14/qml-list.html