XmlRole QML Type▲
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Import Statement: import QtQuick.XmlListModel 2.12
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Group: XmlRole is part of qtquick-models
Detailed Description▲
Property Documentation▲
isKey : bool▲
Defines whether this is a key role. Key roles are used to determine whether a set of values should be updated or added to the XML list model when XmlListModel::reload() is called.
See Also▲
See also XmlListModel
name : string▲
The name for the role. This name is used to access the model data for this role.
For example, the following model has a role named "title", which can be accessed from the view's delegate:
XmlListModel {
id: xmlModel
// ...
XmlRole {
name: "title"
query: "title/string()"
}
}ListView {
model: xmlModel
delegate: Text { text: title }
}query : string▲
The relative XPath expression query for this role. The query must be relative; it cannot start with a '/'.
For example, if there is an XML document like this:
Here are some valid XPath expressions for XmlRole queries on this document:
XmlListModel {
id: model
...
// XmlRole queries will be made on <book> elements
query: "/catalog/book"
// query the book title
XmlRole { name: "title"; query: "title/string()" }
// query the book's year
XmlRole { name: "year"; query: "year/number()" }
// query the book's type (the '@' indicates 'type' is an attribute, not an element)
XmlRole { name: "type"; query: "@type/string()" }
// query the book's first listed author (note in XPath the first index is 1, not 0)
XmlRole { name: "first_author"; query: "author[1]/string()" }
// query the wanted attribute as a boolean
XmlRole { name: "wanted"; query: "boolean(@wanted)" }
}Accessing the model data for the above roles from a delegate:
ListView {
width: 300; height: 200
model: model
delegate: Column {
Text { text: title + " (" + type + ")"; font.bold: wanted }
Text { text: first_author }
Text { text: year }
}See the W3C XPath 2.0 specification for more information.