AudioParameterChoice Class Reference

Provides a class of AudioProcessorParameter that can be used to select an indexed, named choice from a list. More...

#include <juce_AudioParameterChoice.h>

Inheritance diagram for AudioParameterChoice:

Collaboration diagram for AudioParameterChoice:

Public Types
enum	Category {   genericParameter = (0 << 16) | 0,   inputGain = (1 << 16) | 0,   outputGain = (1 << 16) | 1,   inputMeter = (2 << 16) | 0,   outputMeter = (2 << 16) | 1,   compressorLimiterGainReductionMeter = (2 << 16) | 2,   expanderGateGainReductionMeter = (2 << 16) | 3,   analysisMeter = (2 << 16) | 4,   otherMeter = (2 << 16) | 5 }

Public Member Functions
	AudioParameterChoice (const String &parameterID, const String &name, const StringArray &choices, int defaultItemIndex, const String &label=String())
	Creates a AudioParameterChoice with an ID, name, and list of items. More...
	~AudioParameterChoice ()
	Destructor. More...
void	beginChangeGesture ()
	Sends a signal to the host to tell it that the user is about to start changing this parameter. More...
void	endChangeGesture ()
	Tells the host that the user has finished changing this parameter. More...
String	getCurrentChoiceName () const noexcept
	Returns the name of the currently selected item. More...
int	getIndex () const noexcept
	Returns the current index of the selected item. More...
int	getParameterIndex () const noexcept
	Returns the index of this parameter in its parent processor's parameter list. More...
virtual bool	isAutomatable () const
	Returns true if the host can automate this parameter. More...
virtual bool	isMetaParameter () const
	Should return true if this parameter is a "meta" parameter. More...
virtual bool	isOrientationInverted () const
	This can be overridden to tell the host that this parameter operates in the reverse direction. More...
	operator int () const noexcept
	Returns the current index of the selected item. More...
	operator String () const noexcept
	Returns the name of the currently selected item. More...
AudioParameterChoice &	operator= (int newValue)
	Changes the selected item to a new index. More...
void	setValueNotifyingHost (float newValue)
	Your filter can call this when it needs to change one of its parameters. More...

Public Attributes
const Category	category
	Provides access to the parameter's category. More...
const StringArray	choices
	Provides access to the list of choices that this parameter is working with. More...
const String	label
	Provides access to the parameter's label. More...
const String	name
	Provides access to the parameter's name. More...
const String	paramID
	Provides access to the parameter's ID string. More...

Private Member Functions
int	convertFrom0to1 (float) const noexcept
float	convertTo0to1 (int) const noexcept
float	getDefaultValue () const override
	This should return the default value for this parameter. More...
int	getNumSteps () const override
	Returns the number of discrete interval steps that this parameter's range should be quantised into. More...
String	getText (float, int) const override
	Returns a textual version of the supplied parameter value. More...
float	getValue () const override
	Called by the host to find out the value of this parameter. More...
float	getValueForText (const String &) const override
	Should parse a string and return the appropriate value for it. More...
int	limitRange (int) const noexcept
void	setValue (float newValue) override
	The host will call this method to change the value of one of the filter's parameters. More...

Private Attributes
float	defaultValue
float	value

Detailed Description

Provides a class of AudioProcessorParameter that can be used to select an indexed, named choice from a list.

See also

AudioParameterFloat, AudioParameterInt, AudioParameterBool

Member Enumeration Documentation

Category

enum AudioProcessorParameter::Category

inherited

Enumerator
genericParameter
inputGain	If your parameter is not a meter then you should use this category.
outputGain	Currently not used.
inputMeter	The following categories tell the host that this parameter is a meter level value and therefore read-only. Most hosts will display these type of parameters as a meter in the generic view of your plug-in. Pro-Tools will also show the meter in the mixer view.
outputMeter
compressorLimiterGainReductionMeter
expanderGateGainReductionMeter
analysisMeter
otherMeter

Constructor & Destructor Documentation

AudioParameterChoice()

AudioParameterChoice::AudioParameterChoice	(	const String &	parameterID,
		const String &	name,
		const StringArray &	choices,
		int	defaultItemIndex,
		const String &	label = String()
	)

Creates a AudioParameterChoice with an ID, name, and list of items.

On creation, its value is set to the default index.

~AudioParameterChoice()

AudioParameterChoice::~AudioParameterChoice

(

)

Destructor.

Member Function Documentation

beginChangeGesture()

void AudioProcessorParameter::beginChangeGesture ( )

inherited

Sends a signal to the host to tell it that the user is about to start changing this parameter.

This allows the host to know when a parameter is actively being held by the user, and it may use this information to help it record automation. If you call this, it must be matched by a later call to endChangeGesture().

convertFrom0to1()

int AudioParameterChoice::convertFrom0to1 ( float  ) const

privatenoexcept

convertTo0to1()

float AudioParameterChoice::convertTo0to1 ( int  ) const

privatenoexcept

endChangeGesture()

void AudioProcessorParameter::endChangeGesture ( )

inherited

Tells the host that the user has finished changing this parameter.

This allows the host to know when a parameter is actively being held by the user, and it may use this information to help it record automation. A call to this method must follow a call to beginChangeGesture().

getCurrentChoiceName()

String AudioParameterChoice::getCurrentChoiceName ( ) const

inlinenoexcept

Returns the name of the currently selected item.

getDefaultValue()

float AudioParameterChoice::getDefaultValue ( ) const

overrideprivatevirtual

This should return the default value for this parameter.

Implements AudioProcessorParameter.

getIndex()

int AudioParameterChoice::getIndex ( ) const

inlinenoexcept

Returns the current index of the selected item.

References juce::roundToInt().

getNumSteps()

int AudioParameterChoice::getNumSteps ( ) const

overrideprivatevirtual

Returns the number of discrete interval steps that this parameter's range should be quantised into.

If you want a continuous range of values, don't override this method, and allow the default implementation to return AudioProcessor::getDefaultNumParameterSteps(). If your parameter is boolean, then you may want to make this return 2. The value that is returned may or may not be used, depending on the host.

Reimplemented from AudioProcessorParameter.

getParameterIndex()

int AudioProcessorParameter::getParameterIndex ( ) const

inlinenoexceptinherited

Returns the index of this parameter in its parent processor's parameter list.

getText()

String AudioParameterChoice::getText ( float  value, int    ) const

overrideprivatevirtual

Returns a textual version of the supplied parameter value.

The default implementation just returns the floating point value as a string, but this could do anything you need for a custom type of value.

Reimplemented from AudioProcessorParameter.

getValue()

float AudioParameterChoice::getValue ( ) const

overrideprivatevirtual

Called by the host to find out the value of this parameter.

Hosts will expect the value returned to be between 0 and 1.0.

This could be called quite frequently, so try to make your code efficient. It's also likely to be called by non-UI threads, so the code in here should be thread-aware.

Implements AudioProcessorParameter.

getValueForText()

float AudioParameterChoice::getValueForText ( const String &  text ) const

overrideprivatevirtual

Should parse a string and return the appropriate value for it.

Implements AudioProcessorParameter.

isAutomatable()

virtual bool AudioProcessorParameter::isAutomatable ( ) const

virtualinherited

Returns true if the host can automate this parameter.

By default, this returns true.

isMetaParameter()

virtual bool AudioProcessorParameter::isMetaParameter ( ) const

virtualinherited

Should return true if this parameter is a "meta" parameter.

A meta-parameter is a parameter that changes other params. It is used by some hosts (e.g. AudioUnit hosts). By default this returns false.

isOrientationInverted()

virtual bool AudioProcessorParameter::isOrientationInverted ( ) const

virtualinherited

This can be overridden to tell the host that this parameter operates in the reverse direction.

(Not all plugin formats or hosts will actually use this information).

limitRange()

int AudioParameterChoice::limitRange ( int  ) const

privatenoexcept

operator int()

AudioParameterChoice::operator int ( ) const

inlinenoexcept

Returns the current index of the selected item.

operator String()

AudioParameterChoice::operator String ( ) const

inlinenoexcept

Returns the name of the currently selected item.

operator=()

AudioParameterChoice& AudioParameterChoice::operator=

(

int

newValue

)

Changes the selected item to a new index.

setValue()

void AudioParameterChoice::setValue ( float  newValue )

overrideprivatevirtual

The host will call this method to change the value of one of the filter's parameters.

The host may call this at any time, including during the audio processing callback, so the filter has to process this very fast and avoid blocking.

If you want to set the value of a parameter internally, e.g. from your editor component, then don't call this directly - instead, use the setValueNotifyingHost() method, which will also send a message to the host telling it about the change. If the message isn't sent, the host won't be able to automate your parameters properly.

The value passed will be between 0 and 1.0.

Implements AudioProcessorParameter.

setValueNotifyingHost()

void AudioProcessorParameter::setValueNotifyingHost ( float  newValue )

inherited

Your filter can call this when it needs to change one of its parameters.

This could happen when the editor or some other internal operation changes a parameter. This method will call the setValue() method to change the value, and will then send a message to the host telling it about the change.

Note that to make sure the host correctly handles automation, you should call the beginChangeGesture() and endChangeGesture() methods to tell the host when the user has started and stopped changing the parameter.

Member Data Documentation

category

const Category AudioProcessorParameterWithID::category

inherited

Provides access to the parameter's category.

choices

const StringArray AudioParameterChoice::choices

Provides access to the list of choices that this parameter is working with.

defaultValue

float AudioParameterChoice::defaultValue

private

label

const String AudioProcessorParameterWithID::label

inherited

Provides access to the parameter's label.

name

const String AudioProcessorParameterWithID::name

inherited

Provides access to the parameter's name.

paramID

const String AudioProcessorParameterWithID::paramID

inherited

Provides access to the parameter's ID string.

value

float AudioParameterChoice::value

private

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

• juce_AudioParameterChoice.h