This class acts as a typed wrapper around a property inside a ValueTree. More...

#include <juce_CachedValue.h>

Inheritance diagram for CachedValue< Type >:

Collaboration diagram for CachedValue< Type >:

[legend]

Public Member Functions
	CachedValue ()
	Default constructor. More...

	CachedValue (ValueTree &tree, const Identifier &propertyID, UndoManager *undoManager)
	Constructor. More...

	CachedValue (ValueTree &tree, const Identifier &propertyID, UndoManager *undoManager, const Type &defaultToUse)
	Constructor. More...

void	forceUpdateOfCachedValue ()
	Force an update in case the referenced property has been changed from elsewhere. More...

Type	get () const noexcept
	Returns the current value of the property. More...

Type	getDefault () const
	Returns the current fallback default value. More...

Value	getPropertyAsValue ()
	Returns the current property as a Value object. More...

const Identifier &	getPropertyID () const noexcept
	Returns the property ID of the referenced property. More...

ValueTree &	getValueTree () noexcept
	Returns a reference to the ValueTree containing the referenced property. More...

bool	isUsingDefault () const
	Returns true if the current property does not exist and the CachedValue is using the fallback default value instead. More...

	operator Type () const noexcept
	Returns the current value of the property. More...

template<typename OtherType >
bool	operator!= (const OtherType &other) const
	Returns true if the current value of the property (or the fallback value) is not equal to other. More...

Type &	operator* () noexcept
	Dereference operator. More...

Type *	operator-> () noexcept
	Dereference operator. More...

CachedValue &	operator= (const Type &newValue)
	Sets the property. More...

template<typename OtherType >
bool	operator== (const OtherType &other) const
	Returns true if the current value of the property (or the fallback value) is equal to other. More...

void	referTo (ValueTree &tree, const Identifier &property, UndoManager *um)
	Makes the CachedValue refer to the specified property inside the given ValueTree. More...

void	referTo (ValueTree &tree, const Identifier &property, UndoManager *um, const Type &defaultVal)
	Makes the CachedValue refer to the specified property inside the given ValueTree, and specifies a fallback value to use if the property does not exist. More...

void	resetToDefault ()
	Removes the property from the referenced ValueTree and makes the CachedValue return the fallback default value instead. More...

void	resetToDefault (UndoManager *undoManagerToUse)
	Removes the property from the referenced ValueTree and makes the CachedValue return the fallback default value instead. More...

void	setDefault (const Type &value)
	Resets the fallback default value. More...

void	setValue (const Type &newValue, UndoManager *undoManagerToUse)
	Sets the property. More...

Private Member Functions
Type	getTypedValue () const

void	referToWithDefault (ValueTree &, const Identifier &, UndoManager *, const Type &)

void	valueTreeChildAdded (ValueTree &, ValueTree &) override
	This method is called when a child sub-tree is added. More...

void	valueTreeChildOrderChanged (ValueTree &, int, int) override
	This method is called when a tree's children have been re-shuffled. More...

void	valueTreeChildRemoved (ValueTree &, ValueTree &, int) override
	This method is called when a child sub-tree is removed. More...

void	valueTreeParentChanged (ValueTree &) override
	This method is called when a tree has been added or removed from a parent node. More...

void	valueTreePropertyChanged (ValueTree &changedTree, const Identifier &changedProperty) override
	This method is called when a property of this node (or of one of its sub-nodes) has changed. More...

virtual void	valueTreeRedirected (ValueTree &treeWhichHasBeenChanged)
	This method is called when a tree is made to point to a different internal shared object. More...

Private Attributes
Type	cachedValue

Type	defaultValue

Identifier	targetProperty

ValueTree	targetTree

UndoManager *	undoManager

Detailed Description

template<typename Type>
class CachedValue< Type >

This class acts as a typed wrapper around a property inside a ValueTree.

A CachedValue provides an easy way to read and write a ValueTree property with a chosen type. So for example a CachedValue<int> allows you to read or write the property as an int, and a CachedValue<String> lets you work with it as a String.

It also allows efficient access to the value, by caching a copy of it in the type that is being used.

You can give the CachedValue an optional UndoManager which it will use when writing to the underlying ValueTree.

If the property inside the ValueTree is missing, the CachedValue will automatically return an optional default value, which can be specified when initialising the CachedValue.

To create one, you can either use the constructor to attach the CachedValue to a ValueTree, or can create an uninitialised CachedValue with its default constructor and then attach it later with the referTo() methods.

Common types like String, int, double which can be easily converted to a var should work out-of-the-box, but if you want to use more complex custom types, you may need to implement some template specialisations of VariantConverter which this class uses to convert between the type and the ValueTree's internal var.

Constructor & Destructor Documentation

◆ CachedValue() [1/3]

template<typename Type >

CachedValue< Type >::CachedValue ( )

inline

Default constructor.

Creates a default CachedValue not referring to any property. To initialise the object, call one of the referTo() methods.

◆ CachedValue() [2/3]

template<typename Type >

CachedValue< Type >::CachedValue	(	ValueTree &	tree,
		const Identifier &	propertyID,
		UndoManager *	undoManager
	)

inline

Constructor.

Creates a CachedValue referring to a Value property inside a ValueTree. If you use this constructor, the fallback value will be a default-constructed instance of Type.

Parameters

tree	The ValueTree containing the property
propertyID	The identifier of the property
undoManager	The UndoManager to use when writing to the property

References ValueTree::addListener(), and CachedValue< Type >::targetTree.

◆ CachedValue() [3/3]

template<typename Type >

CachedValue< Type >::CachedValue	(	ValueTree &	tree,
		const Identifier &	propertyID,
		UndoManager *	undoManager,
		const Type &	defaultToUse
	)

inline

Constructor.

Creates a default Cached Value referring to a Value property inside a ValueTree, and specifies a fallback value to use if the property does not exist.

Parameters

tree	The ValueTree containing the property
propertyID	The identifier of the property
undoManager	The UndoManager to use when writing to the property
defaultToUse	The fallback default value to use.

References ValueTree::addListener(), and CachedValue< Type >::targetTree.

Member Function Documentation

◆ forceUpdateOfCachedValue()

template<typename Type >

void CachedValue< Type >::forceUpdateOfCachedValue ( )

inline

Force an update in case the referenced property has been changed from elsewhere.

Note: The CachedValue is a ValueTree::Listener and therefore will be informed of changes of the referenced property anyway (and update itself). But this may happen asynchronously. forceUpdateOfCachedValue() forces an update immediately.

References CachedValue< Type >::cachedValue, and CachedValue< Type >::getTypedValue().

Referenced by CachedValue< Type >::resetToDefault(), CachedValue< Type >::setDefault(), and CachedValue< Type >::valueTreePropertyChanged().

◆ get()

template<typename Type >

Type CachedValue< Type >::get ( ) const

inlinenoexcept

Returns the current value of the property.

If the property does not exist, returns the fallback default value.

References CachedValue< Type >::cachedValue.

◆ getDefault()

template<typename Type >

Type CachedValue< Type >::getDefault ( ) const

inline

Returns the current fallback default value.

References CachedValue< Type >::defaultValue, CachedValue< Type >::operator=(), CachedValue< Type >::resetToDefault(), and CachedValue< Type >::setValue().

◆ getPropertyAsValue()

template<typename Type >

Value CachedValue< Type >::getPropertyAsValue ( )

inline

Returns the current property as a Value object.

References ValueTree::getPropertyAsValue(), CachedValue< Type >::targetProperty, CachedValue< Type >::targetTree, and CachedValue< Type >::undoManager.

Referenced by CachedValue< Type >::operator!=().

◆ getPropertyID()

template<typename Type >

const Identifier& CachedValue< Type >::getPropertyID ( ) const

inlinenoexcept

Returns the property ID of the referenced property.

References CachedValue< Type >::targetProperty.

◆ getTypedValue()

template<typename Type >

Type CachedValue< Type >::getTypedValue ( ) const

inlineprivate

References CachedValue< Type >::defaultValue, ValueTree::getPropertyPointer(), CachedValue< Type >::targetProperty, and CachedValue< Type >::targetTree.

Referenced by CachedValue< Type >::forceUpdateOfCachedValue(), and CachedValue< Type >::referToWithDefault().

◆ getValueTree()

template<typename Type >

ValueTree& CachedValue< Type >::getValueTree ( )

inlinenoexcept

Returns a reference to the ValueTree containing the referenced property.

References CachedValue< Type >::targetTree.

◆ isUsingDefault()

template<typename Type >

bool CachedValue< Type >::isUsingDefault ( ) const

inline

Returns true if the current property does not exist and the CachedValue is using the fallback default value instead.

References ValueTree::hasProperty(), CachedValue< Type >::targetProperty, and CachedValue< Type >::targetTree.

Referenced by CachedValue< Type >::operator!=(), and CachedValue< Type >::setValue().

◆ operator Type()

template<typename Type >

CachedValue< Type >::operator Type ( ) const

inlinenoexcept

Returns the current value of the property.

If the property does not exist, returns the fallback default value.

This is the same as calling get().

References CachedValue< Type >::cachedValue.

◆ operator!=()

template<typename Type >

template<typename OtherType >

bool CachedValue< Type >::operator!= ( const OtherType & other ) const

inline

Returns true if the current value of the property (or the fallback value) is not equal to other.

References CachedValue< Type >::cachedValue, CachedValue< Type >::getPropertyAsValue(), and CachedValue< Type >::isUsingDefault().

◆ operator*()

template<typename Type >

Type& CachedValue< Type >::operator* ( )

inlinenoexcept

Dereference operator.

Provides direct access to the property.

References CachedValue< Type >::cachedValue.

◆ operator->()

template<typename Type >

Type* CachedValue< Type >::operator-> ( )

inlinenoexcept

Dereference operator.

Provides direct access to members of the property if it is of object type.

References CachedValue< Type >::cachedValue.

◆ operator=()

template<typename Type >

CachedValue< Type > & CachedValue< Type >::operator= ( const Type & newValue )

inline

Sets the property.

This will actually modify the property in the referenced ValueTree.

References CachedValue< Type >::setValue(), and CachedValue< Type >::undoManager.

Referenced by CachedValue< Type >::getDefault().

◆ operator==()

template<typename Type >

template<typename OtherType >

bool CachedValue< Type >::operator== ( const OtherType & other ) const

inline

Returns true if the current value of the property (or the fallback value) is equal to other.

References CachedValue< Type >::cachedValue.

◆ referTo() [1/2]

template<typename Type >

void CachedValue< Type >::referTo	(	ValueTree &	tree,
		const Identifier &	property,
		UndoManager *	um
	)

inline

Makes the CachedValue refer to the specified property inside the given ValueTree.

References CachedValue< Type >::referToWithDefault().

Referenced by CachedValue< Type >::setDefault().

◆ referTo() [2/2]

template<typename Type >

void CachedValue< Type >::referTo	(	ValueTree &	tree,
		const Identifier &	property,
		UndoManager *	um,
		const Type &	defaultVal
	)

inline

Makes the CachedValue refer to the specified property inside the given ValueTree, and specifies a fallback value to use if the property does not exist.

References CachedValue< Type >::referToWithDefault().

◆ referToWithDefault()

template<typename Type >

void CachedValue< Type >::referToWithDefault	(	ValueTree &	v,
		const Identifier &	i,
		UndoManager *	um,
		const Type &	defaultVal
	)

inlineprivate

References ValueTree::addListener(), CachedValue< Type >::cachedValue, CachedValue< Type >::defaultValue, CachedValue< Type >::getTypedValue(), ValueTree::removeListener(), CachedValue< Type >::targetProperty, CachedValue< Type >::targetTree, and CachedValue< Type >::undoManager.

Referenced by CachedValue< Type >::referTo().

◆ resetToDefault() [1/2]

template<typename Type >

void CachedValue< Type >::resetToDefault ( )

inline

Removes the property from the referenced ValueTree and makes the CachedValue return the fallback default value instead.

References CachedValue< Type >::undoManager.

Referenced by CachedValue< Type >::getDefault().

◆ resetToDefault() [2/2]

template<typename Type >

void CachedValue< Type >::resetToDefault ( UndoManager * undoManagerToUse )

inline

Removes the property from the referenced ValueTree and makes the CachedValue return the fallback default value instead.

References CachedValue< Type >::forceUpdateOfCachedValue(), ValueTree::removeProperty(), CachedValue< Type >::targetProperty, and CachedValue< Type >::targetTree.

◆ setDefault()

template<typename Type >

void CachedValue< Type >::setDefault ( const Type & value )

inline

Resets the fallback default value.

References CachedValue< Type >::defaultValue, CachedValue< Type >::forceUpdateOfCachedValue(), and CachedValue< Type >::referTo().

◆ setValue()

template<typename Type >

void CachedValue< Type >::setValue	(	const Type &	newValue,
		UndoManager *	undoManagerToUse
	)

inline

Sets the property.

This will actually modify the property in the referenced ValueTree.

References CachedValue< Type >::cachedValue, CachedValue< Type >::isUsingDefault(), ValueTree::setProperty(), CachedValue< Type >::targetProperty, and CachedValue< Type >::targetTree.

Referenced by CachedValue< Type >::getDefault(), and CachedValue< Type >::operator=().

◆ valueTreeChildAdded()

template<typename Type >

void CachedValue< Type >::valueTreeChildAdded	(	ValueTree &	parentTree,
		ValueTree &	childWhichHasBeenAdded
	)

inlineoverrideprivatevirtual

This method is called when a child sub-tree is added.

Note that when you register a listener to a tree, it will receive this callback for child changes in both that tree and any of its children, (recursively, at any depth). If your tree has sub-trees but you only want to know about changes to the top level tree, just check the parentTree parameter to make sure it's the one that you're interested in.

Implements ValueTree::Listener.

◆ valueTreeChildOrderChanged()

template<typename Type >

void CachedValue< Type >::valueTreeChildOrderChanged	(	ValueTree &	parentTreeWhoseChildrenHaveMoved,
		int	oldIndex,
		int	newIndex
	)

inlineoverrideprivatevirtual

This method is called when a tree's children have been re-shuffled.

Note that when you register a listener to a tree, it will receive this callback for child changes in both that tree and any of its children, (recursively, at any depth). If your tree has sub-trees but you only want to know about changes to the top level tree, just check the parameter to make sure it's the tree that you're interested in.

Implements ValueTree::Listener.

◆ valueTreeChildRemoved()

template<typename Type >

void CachedValue< Type >::valueTreeChildRemoved	(	ValueTree &	parentTree,
		ValueTree &	childWhichHasBeenRemoved,
		int	indexFromWhichChildWasRemoved
	)

inlineoverrideprivatevirtual

This method is called when a child sub-tree is removed.

Note that when you register a listener to a tree, it will receive this callback for child changes in both that tree and any of its children, (recursively, at any depth). If your tree has sub-trees but you only want to know about changes to the top level tree, just check the parentTree parameter to make sure it's the one that you're interested in.

Implements ValueTree::Listener.

◆ valueTreeParentChanged()

template<typename Type >

void CachedValue< Type >::valueTreeParentChanged ( ValueTree & treeWhoseParentHasChanged )

inlineoverrideprivatevirtual

This method is called when a tree has been added or removed from a parent node.

This callback happens when the tree to which the listener was registered is added or removed from a parent. Unlike the other callbacks, it applies only to the tree to which the listener is registered, and not to any of its children.

Implements ValueTree::Listener.

References JUCE_DECLARE_NON_COPYABLE.

◆ valueTreePropertyChanged()

template<typename Type >

void CachedValue< Type >::valueTreePropertyChanged	(	ValueTree &	treeWhosePropertyHasChanged,
		const Identifier &	property
	)

inlineoverrideprivatevirtual

This method is called when a property of this node (or of one of its sub-nodes) has changed.

The tree parameter indicates which tree has had its property changed, and the property parameter indicates the property.

Note that when you register a listener to a tree, it will receive this callback for property changes in that tree, and also for any of its children, (recursively, at any depth). If your tree has sub-trees but you only want to know about changes to the top level tree, simply check the tree parameter in this callback to make sure it's the tree you're interested in.

Implements ValueTree::Listener.

References CachedValue< Type >::forceUpdateOfCachedValue(), CachedValue< Type >::targetProperty, and CachedValue< Type >::targetTree.

◆ valueTreeRedirected()

virtual void ValueTree::Listener::valueTreeRedirected ( ValueTree & treeWhichHasBeenChanged )

virtualinherited

template<typename Type >

UndoManager* CachedValue< Type >::undoManager

private

Referenced by CachedValue< Type >::getPropertyAsValue(), CachedValue< Type >::operator=(), CachedValue< Type >::referToWithDefault(), and CachedValue< Type >::resetToDefault().

The documentation for this class was generated from the following file:

juce_CachedValue.h

Public Member Functions

Private Member Functions

Private Attributes

Detailed Description

template<typename Type> class CachedValue< Type >

Constructor & Destructor Documentation

◆ CachedValue() [1/3]

◆ CachedValue() [2/3]

◆ CachedValue() [3/3]

Member Function Documentation

◆ forceUpdateOfCachedValue()

◆ get()

◆ getDefault()

◆ getPropertyAsValue()

◆ getPropertyID()

◆ getTypedValue()

◆ getValueTree()

◆ isUsingDefault()

◆ operator Type()

◆ operator!=()

◆ operator*()

◆ operator->()

◆ operator=()

◆ operator==()

◆ referTo() [1/2]

◆ referTo() [2/2]

◆ referToWithDefault()

◆ resetToDefault() [1/2]

◆ resetToDefault() [2/2]

◆ setDefault()

◆ setValue()

◆ valueTreeChildAdded()

◆ valueTreeChildOrderChanged()

◆ valueTreeChildRemoved()

◆ valueTreeParentChanged()

◆ valueTreePropertyChanged()

◆ valueTreeRedirected()

Member Data Documentation

◆ cachedValue

◆ defaultValue

◆ targetProperty

◆ targetTree

◆ undoManager

template<typename Type>
class CachedValue< Type >