QMetaProperty¶

PyQt5.QtCore.QMetaProperty

Description¶

The QMetaProperty class provides meta-data about a property.

Property meta-data is obtained from an object’s meta-object. See property() and propertyCount() for details.

Property Meta-Data¶

A property has a name() and a type(), as well as various attributes that specify its behavior: isReadable(), isWritable(), isDesignable(), isScriptable(), revision(), and isStored().

If the property is an enumeration, isEnumType() returns true; if the property is an enumeration that is also a flag (i.e. its values can be combined using the OR operator), isEnumType() and isFlagType() both return true. The enumerator for these types is available from enumerator().

The property’s values are set and retrieved with read(), write(), and reset(); they can also be changed through QObject’s set and get functions. See setProperty() and property() for details.

Copying and Assignment¶

QMetaProperty objects can be copied by value. However, each copy will refer to the same underlying property meta-data.

Methods¶

__init__(): TODO

__init__(QMetaProperty): TODO

enumerator() → QMetaEnum: Returns the enumerator if this property’s type is an enumerator type; otherwise the returned value is undefined.

See also

isEnumType(), isFlagType().

hasNotifySignal() → bool: Returns true if this property has a corresponding change notify signal; otherwise returns false.

See also

notifySignal().

hasStdCppSet() → bool: Returns true if the property has a C++ setter function that follows Qt’s standard “name” / “setName” pattern. Designer and uic query hasStdCppSet() in order to avoid expensive setProperty() calls. All properties in Qt [should] follow this pattern.

isConstant() → bool

Returns true if the property is constant; otherwise returns false.

A property is constant if the Q_PROPERTY()’s CONSTANT attribute is set.

isDesignable(object: QObject = None) → bool

Returns true if this property is designable for the given object; otherwise returns false.

If no object is given, the function returns false if the Q_PROPERTY()’s DESIGNABLE attribute is false; otherwise returns true (if the attribute is true or is a function or expression).

See also

isScriptable(), isStored().

isEnumType() → bool: Returns true if the property’s type is an enumeration value; otherwise returns false.

See also

enumerator(), isFlagType().

isFinal() → bool

Returns true if the property is final; otherwise returns false.

A property is final if the Q_PROPERTY()’s FINAL attribute is set.

isFlagType() → bool

Returns true if the property’s type is an enumeration value that is used as a flag; otherwise returns false.

Flags can be combined using the OR operator. A flag type is implicitly also an enum type.

See also

isEnumType(), enumerator(), isFlag().

isReadable() → bool: Returns true if this property is readable; otherwise returns false.

See also

isWritable(), read(), isValid().

isResettable() → bool: Returns true if this property can be reset to a default value; otherwise returns false.

See also

reset().

isScriptable(object: QObject = None) → bool

Returns true if the property is scriptable for the given object; otherwise returns false.

If no object is given, the function returns false if the Q_PROPERTY()’s SCRIPTABLE attribute is false; otherwise returns true (if the attribute is true or is a function or expression).

See also

isDesignable(), isStored().

isStored(object: QObject = None) → bool

Returns true if the property is stored for object; otherwise returns false.

If no object is given, the function returns false if the Q_PROPERTY()’s STORED attribute is false; otherwise returns true (if the attribute is true or is a function or expression).

See also

isDesignable(), isScriptable().

isUser(object: QObject = None) → bool

Returns true if this property is designated as the USER property, i.e., the one that the user can edit for object or that is significant in some other way. Otherwise it returns false. e.g., the text property is the USER editable property of a QLineEdit.

If object is null, the function returns false if the Q_PROPERTY()’s USER attribute is false. Otherwise it returns true.

isValid() → bool: TODO

isWritable() → bool: Returns true if this property is writable; otherwise returns false.

See also

isReadable(), write().

name() → str: Returns this property’s name.

See also

type(), typeName().

notifySignal() → QMetaMethod: Returns the QMetaMethod instance of the property change notifying signal if one was specified, otherwise returns an invalid QMetaMethod.

See also

hasNotifySignal().

notifySignalIndex() → int: Returns the index of the property change notifying signal if one was specified, otherwise returns -1.

See also

hasNotifySignal().

propertyIndex() → int: Returns this property’s index.

read(QObject) → Any: Reads the property’s value from the given object. Returns the value if it was able to read it; otherwise returns an invalid variant.

See also

write(), reset(), isReadable().

relativePropertyIndex() → int: TODO

reset(QObject) → bool

Resets the property for the given object with a reset method. Returns true if the reset worked; otherwise returns false.

Reset methods are optional; only a few properties support them.

See also

read(), write().

type() → Type: Returns this property’s type. The return value is one of the values of the Type enumeration.

See also

userType(), typeName(), name().

typeName() → str: Returns the name of this property’s type.

See also

type(), name().

userType() → int: Returns this property’s user type. The return value is one of the values that are registered with QMetaType, or QMetaType::UnknownType if the type is not registered.

See also

type(), QMetaType, typeName().

write(QObject, Any) → bool

Writes value as the property’s value to the given object. Returns true if the write succeeded; otherwise returns false.

If value is not of the same type type as the property, a conversion is attempted. An empty QVariant() is equivalent to a call to reset() if this property is resetable, or setting a default-constructed object otherwise.

See also

read(), reset(), isWritable().