slint::interpreter::Value Class

class Value;

C++

#include <slint-interpreter.h>

C++

This is a dynamically typed value used in the Slint interpreter. It can hold a value of different types, and you should use the different overloaded constructors and the to_xxx() functions to access the value within.

It is also possible to query the type the value holds by calling the Value::type() function.

Note that models are only represented in one direction: You can create a slint::Model<Value> in C++, store it in a std::shared_ptr ↗ and construct Value from it. Then you can set it on a property in your .slint code that was declared to be either an array (property <[sometype]> foo;) or an object literal (property <{foo: string, bar: int}> my_prop;). Such properties are dynamic and accept models implemented in C++.

Value v(42.0); // Creates a value that holds a double with the value 42.

Value some_value = ...;
// Check if the value has a string
if (std::optional<slint::SharedString> string_value = some_value.to_string())
    do_something(*string_value);  // Extract the string by de-referencing

C++

Public Types

Type

ValueType using slint::interpreter::Value::Type =  ValueType

A convenience alias for the value type enum.

Friends

operator==

bool operator==(const Value &a, const Value &b)

Returns true if a and b hold values of the same type and the underlying vales are equal.

Public Functions

Value

slint::interpreter::Value::Value()

Constructs a new value of type Value::Type::Void.

Value

slint::interpreter::Value::Value(const Value &other)

Constructs a new value by copying other.

Value

slint::interpreter::Value::Value(Value &&other)

Constructs a new value by moving other to this.

operator=

Value & slint::interpreter::Value::operator=(const Value &other)

Assigns the value other to this.

operator=

Value & slint::interpreter::Value::operator=(Value &&other)

Moves the value other to this.

~Value

slint::interpreter::Value::~Value()

Destroys the value.

to_number

std::optional< double > slint::interpreter::Value::to_number() const

Returns a std::optional ↗ that contains a double if the type of this Value is Type::Double, otherwise an empty optional is returned.

to_string

std::optional< slint::SharedString > slint::interpreter::Value::to_string() const

Returns a std::optional ↗ that contains a string if the type of this Value is Type::String, otherwise an empty optional is returned.

to_bool

std::optional< bool > slint::interpreter::Value::to_bool() const

Returns a std::optional ↗ that contains a bool if the type of this Value is Type::Bool, otherwise an empty optional is returned.

to_array

std::optional< slint::SharedVector< Value > > slint::interpreter::Value::to_array() const

Returns a std::optional ↗ that contains a vector of values if the type of this Value is Type::Model, otherwise an empty optional is returned.

The vector will be constructed by serializing all the elements of the model.

to_brush

std::optional< slint::Brush > slint::interpreter::Value::to_brush() const

Returns a std::optional ↗ that contains a brush if the type of this Value is Type::Brush, otherwise an empty optional is returned.

to_struct

std::optional< Struct > slint::interpreter::Value::to_struct() const

Returns a std::optional ↗ that contains a Struct if the type of this Value is Type::Struct, otherwise an empty optional is returned.

to_image

std::optional< Image > slint::interpreter::Value::to_image() const

Returns a std::optional ↗ that contains an Image if the type of this Value is Type::Image, otherwise an empty optional is returned.

Value

slint::interpreter::Value::Value(double value)

Constructs a new Value that holds the double value.

Value

slint::interpreter::Value::Value(int value)

Constructs a new Value that holds the int value. Internally this is stored as a double and Value::type() will return Value::Type::Number.

Value

slint::interpreter::Value::Value(const SharedString &str)

Constructs a new Value that holds the string str.

Value

slint::interpreter::Value::Value(bool b)

Constructs a new Value that holds the boolean b.

Value

slint::interpreter::Value::Value(const SharedVector< Value > &v)

Constructs a new Value that holds the value vector v as a model.

Value

slint::interpreter::Value::Value(const std::shared_ptr< slint::Model< Value > > &m)

Constructs a new Value that holds the value model m.

Value

slint::interpreter::Value::Value(const slint::Brush &brush)

Constructs a new Value that holds the brush b.

Value

slint::interpreter::Value::Value(const Struct &struc)

Constructs a new Value that holds the Struct struc.

Value

slint::interpreter::Value::Value(const Image &img)

Constructs a new Value that holds the Image img.

type

Type slint::interpreter::Value::type() const

Returns the type the variant holds.