QQmlListReference Class
The QQmlListReference class allows the manipulation of QQmlListProperty properties. More...
| Header: | #include <QQmlListReference> |
| qmake: | QT += qml |
| Since: | Qt 5.0 |
This class was introduced in Qt 5.0.
Detailed Description
QQmlListReference allows C++ programs to read from, and assign values to a QML list property in a simple and type-safe way. A QQmlListReference can be created by passing an object and property name or through a QQmlProperty instance. These two are equivalent:
QQmlListReference ref1(object, "children"); QQmlProperty ref2(object, "children"); QQmlListReference ref2 = qvariant_cast<QQmlListReference>(ref2.read());
Not all QML list properties support all operations. A set of methods, canAppend(), canAt(), canClear() and canCount() allow programs to query whether an operation is supported on a given property.
QML list properties are type-safe. Only QObject's that derive from the correct base class can be assigned to the list. The listElementType() method can be used to query the QMetaObject of the QObject type supported. Attempting to add objects of the incorrect type to a list property will fail.
Like with normal lists, when accessing a list element by index, it is the callers responsibility to ensure that it does not request an out of range element using the count() method before calling at().