PropCategory Class Reference

Category properties define a tree-relationship between all properties in a property map. More...

Inheritance diagram for PropCategory:

Public Member Functions

std::vector< Property >	features (Error &err=Error::Default()) const Retrieves the list of properties in a property category.
Public Member Functions inherited from Property
	Property ()=default Creates an invalid object.
bool	is_valid () const noexcept Checks whether this property is a valid object.
bool	operator== (const Property &other) const noexcept Checks whether a property object refers to the same property as another property object.
bool	operator!= (const Property &other) const noexcept Checks whether a property object refers to a different property as another property object.
bool	operator< (const Property &other) const noexcept Provides an ordering of property objects.
PropType	type (Error &err=Error::Default()) const Returns the type of the property.
std::string	name (Error &err=Error::Default()) const Returns the name of the property.
bool	isAvailable (Error &err=Error::Default()) const Checks whether a property is currently available.
bool	isLocked (Error &err=Error::Default()) const Checks whether a property is currently locked.
bool	isLikelyLockedByStream (Error &err=Error::Default()) const Tries to determine whether a property is locked because a data stream is active.
bool	isReadOnly (Error &err=Error::Default()) const Checks whether a property is read-only.
PropVisibility	visibility (Error &err=Error::Default()) const Returns a visibility hint for the property.
std::string	displayName (Error &err=Error::Default()) const Returns the display name of the property.
std::string	tooltip (Error &err=Error::Default()) const Returns a tooltip for the property.
std::string	description (Error &err=Error::Default()) const Returns a description for the property.
PropCommand	asCommand (Error &err=Error::Default()) const Converts this property into a PropCommand.
PropInteger	asInteger (Error &err=Error::Default()) const Converts this property into a PropInteger.
PropBoolean	asBoolean (Error &err=Error::Default()) const Converts this property into a PropBoolean.
PropFloat	asFloat (Error &err=Error::Default()) const Converts this property into a PropFloat.
PropString	asString (Error &err=Error::Default()) const Converts this property into a PropString.
PropEnumeration	asEnumeration (Error &err=Error::Default()) const Converts this property into a PropEnumeration.
PropEnumEntry	asEnumEntry (Error &err=Error::Default()) const Converts this property into a PropEnumEntry.
PropRegister	asRegister (Error &err=Error::Default()) const Converts this property into a PropRegister.
PropCategory	asCategory (Error &=Error::Default()) const Converts this property into a PropCategory.
NotificationToken	eventAddNotification (NotificationHandler cb, Error &err=Error::Default()) Registers a new property notification event handler.
bool	eventRemoveNotification (NotificationToken token, Error &err=Error::Default()) Unregisters a previously registered property notification event handler.
bool	isSelector (Error &err=Error::Default()) const Indicates whether this property's value changes the meaning and/or value of other properties.
std::vector< Property >	selectedProperties (Error &err=Error::Default()) const Returns the list of properties whose values' meaning depend on this property.

Additional Inherited Members

Public Types inherited from Property
using	NotificationHandler = std::function< void(Property &prop)> Function prototype for property notification event handlers.
using	NotificationToken = void * Represents a registered callback.

Detailed Description

Category properties define a tree-relationship between all properties in a property map.

The root of the tree is always the category property with the name Root.

To find which properties are linked from a category, use PropCategory::features().

Categories can contain other categories recursively. A very simple category tree might look like this:

Root (category)
- AcquisitionControl (category)
  - AcquisitionStart (command)
  - AcquisitionStop (command)
  - AcquisitionFrameRate (float)
- ImageFormatControl (category)
  - Width (integer)
  - Height (integer)

PropCategory instances are created in two ways:

By converting a property known to be a category property using Property::asCategory()
By directly querying a typed known property using PropertyMap::findCategory().

Member Function Documentation

◆ features()

std::vector< Property > features ( Error & err = Error::Default() ) const

inline

Retrieves the list of properties in a property category.

Parameters

[out] err Reference to an error handler. See Error Handling for details.

Returns: A std::vector containing the properties in this category.
If an error occurred, the function returns an empty vector. Check the err output parameter for details.