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QQmlScriptString Class

The QQmlScriptString class encapsulates a script and its context. More...

Header: #include <QQmlScriptString>
qmake: QT += qml

Public Functions

QQmlScriptString(const QQmlScriptString &other)
QQmlScriptString()
QQmlScriptString & operator=(const QQmlScriptString &other)
bool booleanLiteral(bool *ok) const
bool isEmpty() const
bool isNullLiteral() const
bool isUndefinedLiteral() const
qreal numberLiteral(bool *ok) const
QString stringLiteral() const
bool operator!=(const QQmlScriptString &other) const
bool operator==(const QQmlScriptString &other) const

Detailed Description

QQmlScriptString is used to create QObject properties that accept a script "assignment" from QML.

Normally, the following QML would result in a binding being established for the script property; i.e. script would be assigned the value obtained from running myObj.value = Math.max(myValue, 100)

MyType {
    script: myObj.value = Math.max(myValue, 100)
}

If instead the property had a type of QQmlScriptString, the script itself -- myObj.value = Math.max(myValue, 100) -- would be passed to the script property and the class could choose how to handle it. Typically, the class will evaluate the script at some later time using a QQmlExpression.

QQmlExpression expr(scriptString);
expr.evaluate();

See also QQmlExpression.

Member Function Documentation

QQmlScriptString::QQmlScriptString(const QQmlScriptString &other)

Copies other.

QQmlScriptString::QQmlScriptString()

Constructs an empty instance.

QQmlScriptString &QQmlScriptString::operator=(const QQmlScriptString &other)

Assigns other to this.

bool QQmlScriptString::booleanLiteral(bool *ok) const

If the content of the QQmlScriptString is a boolean literal, returns the boolean value and sets ok to true. Otherwise returns false and sets ok to false.

bool QQmlScriptString::isEmpty() const

Returns whether the QQmlScriptString is empty.

bool QQmlScriptString::isNullLiteral() const

Returns whether the content of the QQmlScriptString is the null literal.

bool QQmlScriptString::isUndefinedLiteral() const

Returns whether the content of the QQmlScriptString is the undefined literal.

qreal QQmlScriptString::numberLiteral(bool *ok) const

If the content of the QQmlScriptString is a number literal, returns that number and sets ok to true. Otherwise returns 0.0 and sets ok to false.

QString QQmlScriptString::stringLiteral() const

If the content of the QQmlScriptString is a string literal, returns that string. Otherwise returns a null QString.

bool QQmlScriptString::operator!=(const QQmlScriptString &other) const

Returns true if this and the other QQmlScriptString objects are different.

See also operator==().

bool QQmlScriptString::operator==(const QQmlScriptString &other) const

Returns true if this and the other QQmlScriptString objects are equal.

See also operator!=().

© The Qt Company Ltd
Licensed under the GNU Free Documentation License, Version 1.3.
https://doc.qt.io/qt-5.15/qqmlscriptstring.html