Slider Class Reference

A slider control for changing a value. More...

Inherits Component, SettableTooltipClient, AsyncUpdater, ButtonListener, LabelListener, and Value::Listener.

List of all members.

Public Types
enum	SliderStyle {   LinearHorizontal, LinearVertical, LinearBar, Rotary,   RotaryHorizontalDrag, RotaryVerticalDrag, IncDecButtons, TwoValueHorizontal,   TwoValueVertical, ThreeValueHorizontal, ThreeValueVertical }
	The types of slider available. More...
enum	IncDecButtonMode { incDecButtonsNotDraggable, incDecButtonsDraggable_AutoDirection, incDecButtonsDraggable_Horizontal, incDecButtonsDraggable_Vertical }
	Used by setIncDecButtonsMode(). More...
enum	TextEntryBoxPosition {   NoTextBox, TextBoxLeft, TextBoxRight, TextBoxAbove,   TextBoxBelow }
	The position of the slider's text-entry box. More...
enum	ColourIds {   backgroundColourId = 0x1001200, thumbColourId = 0x1001300, trackColourId = 0x1001310, rotarySliderFillColourId = 0x1001311,   rotarySliderOutlineColourId = 0x1001312, textBoxTextColourId = 0x1001400, textBoxBackgroundColourId = 0x1001500, textBoxHighlightColourId = 0x1001600,   textBoxOutlineColourId = 0x1001700 }
	A set of colour IDs to use to change the colour of various aspects of the slider. More...
Public Member Functions
	Slider (const String &componentName)
	Creates a slider.
	~Slider ()
	Destructor.
void	setSliderStyle (SliderStyle newStyle)
	Changes the type of slider interface being used.
SliderStyle	getSliderStyle () const
	Returns the slider's current style.
void	setRotaryParameters (float startAngleRadians, float endAngleRadians, bool stopAtEnd)
	Changes the properties of a rotary slider.
void	setMouseDragSensitivity (int distanceForFullScaleDrag)
	Sets the distance the mouse has to move to drag the slider across the full extent of its range.
void	setVelocityBasedMode (bool isVelocityBased)
	Changes the way the the mouse is used when dragging the slider.
bool	getVelocityBasedMode () const
	Returns true if velocity-based mode is active.
void	setVelocityModeParameters (double sensitivity=1.0, int threshold=1, double offset=0.0, bool userCanPressKeyToSwapMode=true)
	Changes aspects of the scaling used when in velocity-sensitive mode.
double	getVelocitySensitivity () const
	Returns the velocity sensitivity setting.
int	getVelocityThreshold () const
	Returns the velocity threshold setting.
double	getVelocityOffset () const
	Returns the velocity offset setting.
bool	getVelocityModeIsSwappable () const
	Returns the velocity user key setting.
void	setSkewFactor (double factor)
	Sets up a skew factor to alter the way values are distributed.
void	setSkewFactorFromMidPoint (double sliderValueToShowAtMidPoint)
	Sets up a skew factor to alter the way values are distributed.
double	getSkewFactor () const
	Returns the current skew factor.
void	setIncDecButtonsMode (IncDecButtonMode mode)
	When the style is IncDecButtons, this lets you turn on a mode where the mouse can be dragged on the buttons to drag the values.
void	setTextBoxStyle (TextEntryBoxPosition newPosition, bool isReadOnly, int textEntryBoxWidth, int textEntryBoxHeight)
	Changes the location and properties of the text-entry box.
const TextEntryBoxPosition	getTextBoxPosition () const
	Returns the status of the text-box.
int	getTextBoxWidth () const
	Returns the width used for the text-box.
int	getTextBoxHeight () const
	Returns the height used for the text-box.
void	setTextBoxIsEditable (bool shouldBeEditable)
	Makes the text-box editable.
bool	isTextBoxEditable () const
	Returns true if the text-box is read-only.
void	showTextBox ()
	If the text-box is editable, this will give it the focus so that the user can type directly into it.
void	hideTextBox (bool discardCurrentEditorContents)
	If the text-box currently has focus and is being edited, this resets it and takes keyboard focus away from it.
void	setValue (double newValue, bool sendUpdateMessage=true, bool sendMessageSynchronously=false)
	Changes the slider's current value.
double	getValue () const
	Returns the slider's current value.
Value &	getValueObject ()
	Returns the Value object that represents the slider's current position.
void	setRange (double newMinimum, double newMaximum, double newInterval=0)
	Sets the limits that the slider's value can take.
double	getMaximum () const
	Returns the current maximum value.
double	getMinimum () const
	Returns the current minimum value.
double	getInterval () const
	Returns the current step-size for values.
double	getMinValue () const
	For a slider with two or three thumbs, this returns the lower of its values.
Value &	getMinValueObject ()
	For a slider with two or three thumbs, this returns the lower of its values.
void	setMinValue (double newValue, bool sendUpdateMessage=true, bool sendMessageSynchronously=false, bool allowNudgingOfOtherValues=false)
	For a slider with two or three thumbs, this sets the lower of its values.
double	getMaxValue () const
	For a slider with two or three thumbs, this returns the higher of its values.
Value &	getMaxValueObject ()
	For a slider with two or three thumbs, this returns the higher of its values.
void	setMaxValue (double newValue, bool sendUpdateMessage=true, bool sendMessageSynchronously=false, bool allowNudgingOfOtherValues=false)
	For a slider with two or three thumbs, this sets the lower of its values.
void	addListener (SliderListener *listener)
	Adds a listener to be called when this slider's value changes.
void	removeListener (SliderListener *listener)
	Removes a previously-registered listener.
void	setDoubleClickReturnValue (bool isDoubleClickEnabled, double valueToSetOnDoubleClick)
	This lets you choose whether double-clicking moves the slider to a given position.
double	getDoubleClickReturnValue (bool &isEnabled) const
	Returns the values last set by setDoubleClickReturnValue() method.
void	setChangeNotificationOnlyOnRelease (bool onlyNotifyOnRelease)
	Tells the slider whether to keep sending change messages while the user is dragging the slider.
void	setSliderSnapsToMousePosition (bool shouldSnapToMouse)
	This lets you change whether the slider thumb jumps to the mouse position when you click.
void	setPopupDisplayEnabled (bool isEnabled, Component *parentComponentToUse)
	If enabled, this gives the slider a pop-up bubble which appears while the slider is being dragged.
void	setPopupMenuEnabled (bool menuEnabled)
	If this is set to true, then right-clicking on the slider will pop-up a menu to let the user change the way it works.
void	setScrollWheelEnabled (bool enabled)
	This can be used to stop the mouse scroll-wheel from moving the slider.
int	getThumbBeingDragged () const
	Returns a number to indicate which thumb is currently being dragged by the mouse.
virtual void	startedDragging ()
	Callback to indicate that the user is about to start dragging the slider.
virtual void	stoppedDragging ()
	Callback to indicate that the user has just stopped dragging the slider.
virtual void	valueChanged ()
	Callback to indicate that the user has just moved the slider.
virtual int	valueChanged (double)
	Callback to indicate that the user has just moved the slider.
virtual double	getValueFromText (const String &text)
	Subclasses can override this to convert a text string to a value.
virtual const String	getTextFromValue (double value)
	Turns the slider's current value into a text string.
void	setTextValueSuffix (const String &suffix)
	Sets a suffix to append to the end of the numeric value when it's displayed as a string.
const String	getTextValueSuffix () const
	Returns the suffix that was set by setTextValueSuffix().
virtual double	proportionOfLengthToValue (double proportion)
	Allows a user-defined mapping of distance along the slider to its value.
virtual double	valueToProportionOfLength (double value)
	Allows a user-defined mapping of value to the position of the slider along its length.
float	getPositionOfValue (double value)
	Returns the X or Y coordinate of a value along the slider's length.
virtual double	snapValue (double attemptedValue, bool userIsDragging)
	This can be overridden to allow the slider to snap to user-definable values.
void	updateText ()
	This can be called to force the text box to update its contents.
bool	isHorizontal () const
	True if the slider moves horizontally.
bool	isVertical () const
	True if the slider moves vertically.
Protected Member Functions
void	labelTextChanged (Label *)
void	paint (Graphics &g)
void	resized ()
void	mouseDown (const MouseEvent &e)
void	mouseUp (const MouseEvent &e)
void	mouseDrag (const MouseEvent &e)
void	mouseDoubleClick (const MouseEvent &e)
void	mouseWheelMove (const MouseEvent &e, float wheelIncrementX, float wheelIncrementY)
void	modifierKeysChanged (const ModifierKeys &modifiers)
void	buttonClicked (Button *button)
void	lookAndFeelChanged ()
void	enablementChanged ()
void	focusOfChildComponentChanged (FocusChangeType cause)
void	handleAsyncUpdate ()
void	colourChanged ()
void	valueChanged (Value &value)
int	getNumDecimalPlacesToDisplay () const throw ()
	Returns the best number of decimal places to use when displaying numbers.

---

Detailed Description

A slider control for changing a value.

The slider can be horizontal, vertical, or rotary, and can optionally have a text-box inside it to show an editable display of the current value.

To use it, create a Slider object and use the setSliderStyle() method to set up the type you want. To set up the text-entry box, use setTextBoxStyle().

To define the values that it can be set to, see the setRange() and setValue() methods.

There are also lots of custom tweaks you can do by subclassing and overriding some of the virtual methods, such as changing the scaling, changing the format of the text display, custom ways of limiting the values, etc.

You can register SliderListeners with a slider, which will be informed when the value changes, or a subclass can override valueChanged() to be informed synchronously.

See also:

SliderListener

---

Member Enumeration Documentation

enum Slider::SliderStyle

The types of slider available.

See also:

setSliderStyle, setRotaryParameters

Enumerator:

LinearHorizontal	A traditional horizontal slider.
LinearVertical	A traditional vertical slider.
LinearBar	A horizontal bar slider with the text label drawn on top of it.
Rotary	A rotary control that you move by dragging the mouse in a circular motion, like a knob. See also: setRotaryParameters
RotaryHorizontalDrag	A rotary control that you move by dragging the mouse left-to-right. See also: setRotaryParameters
RotaryVerticalDrag	A rotary control that you move by dragging the mouse up-and-down. See also: setRotaryParameters
IncDecButtons	A pair of buttons that increment or decrement the slider's value by the increment set in setRange().
TwoValueHorizontal	A horizontal slider that has two thumbs instead of one, so it can show a minimum and maximum value. See also: setMinValue, setMaxValue
TwoValueVertical	A vertical slider that has two thumbs instead of one, so it can show a minimum and maximum value. See also: setMinValue, setMaxValue
ThreeValueHorizontal	A horizontal slider that has three thumbs instead of one, so it can show a minimum and maximum value, with the current value being somewhere between them. See also: setMinValue, setMaxValue
ThreeValueVertical	A vertical slider that has three thumbs instead of one, so it can show a minimum and maximum value, with the current value being somewhere between them. See also: setMinValue, setMaxValue

enum Slider::IncDecButtonMode

Used by setIncDecButtonsMode().

Enumerator:

incDecButtonsNotDraggable
incDecButtonsDraggable_AutoDirection
incDecButtonsDraggable_Horizontal
incDecButtonsDraggable_Vertical

enum Slider::TextEntryBoxPosition

The position of the slider's text-entry box.

See also:

setTextBoxStyle

Enumerator:

NoTextBox	Doesn't display a text box.
TextBoxLeft	Puts the text box to the left of the slider, vertically centred.
TextBoxRight	Puts the text box to the right of the slider, vertically centred.
TextBoxAbove	Puts the text box above the slider, horizontally centred.
TextBoxBelow	Puts the text box below the slider, horizontally centred.

enum Slider::ColourIds

A set of colour IDs to use to change the colour of various aspects of the slider.

These constants can be used either via the Component::setColour(), or LookAndFeel::setColour() methods.

See also:

Component::setColour, Component::findColour, LookAndFeel::setColour, LookAndFeel::findColour

Enumerator:

backgroundColourId	A colour to use to fill the slider's background.
thumbColourId	The colour to draw the thumb with. It's up to the look and feel class how this is used.
trackColourId	The colour to draw the groove that the thumb moves along.
rotarySliderFillColourId	For rotary sliders, this colour fills the outer curve.
rotarySliderOutlineColourId	For rotary sliders, this colour is used to draw the outer curve's outline.
textBoxTextColourId	The colour for the text in the text-editor box used for editing the value.
textBoxBackgroundColourId	The background colour for the text-editor box.
textBoxHighlightColourId	The text highlight colour for the text-editor box.
textBoxOutlineColourId	The colour to use for a border around the text-editor box.

---

Constructor & Destructor Documentation

Slider::Slider

(

const String &

componentName

)

[explicit]

Creates a slider.

When created, you'll need to set up the slider's style and range with setSliderStyle(), setRange(), etc.

Slider::~Slider

(

)

Destructor.

---

Member Function Documentation

void Slider::setSliderStyle

(

SliderStyle

newStyle

)

Changes the type of slider interface being used.

Parameters:

newStyle

the type of interface

See also:

setRotaryParameters, setVelocityBasedMode,

SliderStyle Slider::getSliderStyle

(

)

const

Returns the slider's current style.

See also:

setSliderStyle

void Slider::setRotaryParameters	(	float	startAngleRadians,
		float	endAngleRadians,
		bool	stopAtEnd
	)

Changes the properties of a rotary slider.

Parameters:

	startAngleRadians	the angle (in radians, clockwise from the top) at which the slider's minimum value is represented
	endAngleRadians	the angle (in radians, clockwise from the top) at which the slider's maximum value is represented. This must be greater than startAngleRadians
	stopAtEnd	if true, then when the slider is dragged around past the minimum or maximum, it'll stop there; if false, it'll wrap back to the opposite value

void Slider::setMouseDragSensitivity

(

int

distanceForFullScaleDrag

)

Sets the distance the mouse has to move to drag the slider across the full extent of its range.

This only applies when in modes like RotaryHorizontalDrag, where it's using relative mouse movements to adjust the slider.

void Slider::setVelocityBasedMode

(

bool

isVelocityBased

)

Changes the way the the mouse is used when dragging the slider.

If true, this will turn on velocity-sensitive dragging, so that the faster the mouse moves, the bigger the movement to the slider. This helps when making accurate adjustments if the slider's range is quite large.

If false, the slider will just try to snap to wherever the mouse is.

bool Slider::getVelocityBasedMode

(

)

const

Returns true if velocity-based mode is active.

See also:

setVelocityBasedMode

void Slider::setVelocityModeParameters	(	double	sensitivity = 1.0,
		int	threshold = 1,
		double	offset = 0.0,
		bool	userCanPressKeyToSwapMode = true
	)

Changes aspects of the scaling used when in velocity-sensitive mode.

These apply when you've used setVelocityBasedMode() to turn on velocity mode, or if you're holding down ctrl.

Parameters:

	sensitivity	higher values than 1.0 increase the range of acceleration used
	threshold	the minimum number of pixels that the mouse needs to move for it to be treated as a movement
	offset	values greater than 0.0 increase the minimum speed that will be used when the threshold is reached
	userCanPressKeyToSwapMode	if true, then the user can hold down the ctrl or command key to toggle velocity-sensitive mode

double Slider::getVelocitySensitivity

(

)

const

Returns the velocity sensitivity setting.

See also:

setVelocityModeParameters

int Slider::getVelocityThreshold

(

)

const

Returns the velocity threshold setting.

See also:

setVelocityModeParameters

double Slider::getVelocityOffset

(

)

const

Returns the velocity offset setting.

See also:

setVelocityModeParameters

bool Slider::getVelocityModeIsSwappable

(

)

const

Returns the velocity user key setting.

See also:

setVelocityModeParameters

void Slider::setSkewFactor

(

double

factor

)

Sets up a skew factor to alter the way values are distributed.

You may want to use a range of values on the slider where more accuracy is required towards one end of the range, so this will logarithmically spread the values across the length of the slider.

If the factor is < 1.0, the lower end of the range will fill more of the slider's length; if the factor is > 1.0, the upper end of the range will be expanded instead. A factor of 1.0 doesn't skew it at all.

To set the skew position by using a mid-point, use the setSkewFactorFromMidPoint() method instead.

See also:

getSkewFactor, setSkewFactorFromMidPoint

void Slider::setSkewFactorFromMidPoint

(

double

sliderValueToShowAtMidPoint

)

Sets up a skew factor to alter the way values are distributed.

This allows you to specify the slider value that should appear in the centre of the slider's visible range.

See also:

setSkewFactor, getSkewFactor

double Slider::getSkewFactor

(

)

const

Returns the current skew factor.

See setSkewFactor for more info.

See also:

setSkewFactor, setSkewFactorFromMidPoint

void Slider::setIncDecButtonsMode

(

IncDecButtonMode

mode

)

When the style is IncDecButtons, this lets you turn on a mode where the mouse can be dragged on the buttons to drag the values.

By default this is turned off. When enabled, clicking on the buttons still works them as normal, but by holding down the mouse on a button and dragging it a little distance, it flips into a mode where the value can be dragged. The drag direction can either be set explicitly to be vertical or horizontal, or can be set to incDecButtonsDraggable_AutoDirection so that it depends on whether the buttons are side-by-side or above each other.

void Slider::setTextBoxStyle	(	TextEntryBoxPosition	newPosition,
		bool	isReadOnly,
		int	textEntryBoxWidth,
		int	textEntryBoxHeight
	)

Changes the location and properties of the text-entry box.

Parameters:

	newPosition	where it should go (or NoTextBox to not have one at all)
	isReadOnly	if true, it's a read-only display
	textEntryBoxWidth	the width of the text-box in pixels. Make sure this leaves enough room for the slider as well!
	textEntryBoxHeight	the height of the text-box in pixels. Make sure this leaves enough room for the slider as well!

See also:

setTextBoxIsEditable, getValueFromText, getTextFromValue

const TextEntryBoxPosition Slider::getTextBoxPosition

(

)

const

Returns the status of the text-box.

See also:

setTextBoxStyle

int Slider::getTextBoxWidth

(

)

const

Returns the width used for the text-box.

See also:

setTextBoxStyle

int Slider::getTextBoxHeight

(

)

const

Returns the height used for the text-box.

See also:

setTextBoxStyle

void Slider::setTextBoxIsEditable

(

bool

shouldBeEditable

)

Makes the text-box editable.

By default this is true, and the user can enter values into the textbox, but it can be turned off if that's not suitable.

See also:

setTextBoxStyle, getValueFromText, getTextFromValue

bool Slider::isTextBoxEditable

(

)

const

Returns true if the text-box is read-only.

See also:

setTextBoxStyle

void Slider::showTextBox

(

)

If the text-box is editable, this will give it the focus so that the user can type directly into it.

This is basically the effect as the user clicking on it.

void Slider::hideTextBox

(

bool

discardCurrentEditorContents

)

If the text-box currently has focus and is being edited, this resets it and takes keyboard focus away from it.

Parameters:

discardCurrentEditorContents

if true, the slider's value will be left unchanged; if false, the current contents of the text editor will be used to set the slider position before it is hidden.

void Slider::setValue	(	double	newValue,
		bool	sendUpdateMessage = true,
		bool	sendMessageSynchronously = false
	)

Changes the slider's current value.

This will trigger a callback to SliderListener::sliderValueChanged() for any listeners that are registered, and will synchronously call the valueChanged() method in case subclasses want to handle it.

Parameters:

	newValue	the new value to set - this will be restricted by the minimum and maximum range, and will be snapped to the nearest interval if one has been set
	sendUpdateMessage	if false, a change to the value will not trigger a call to any SliderListeners or the valueChanged() method
	sendMessageSynchronously	if true, then a call to the SliderListeners will be made synchronously; if false, it will be asynchronous

double Slider::getValue

(

)

const

Returns the slider's current value.

Value& Slider::getValueObject

(

)

Returns the Value object that represents the slider's current position.

You can use this Value object to connect the slider's position to external values or setters, either by taking a copy of the Value, or by using Value::referTo() to make it point to your own Value object.

See also:

Value, getMaxValue, getMinValueObject

void Slider::setRange	(	double	newMinimum,
		double	newMaximum,
		double	newInterval = 0
	)

Sets the limits that the slider's value can take.

Parameters:

	newMinimum	the lowest value allowed
	newMaximum	the highest value allowed
	newInterval	the steps in which the value is allowed to increase - if this is not zero, the value will always be (newMinimum + (newInterval * an integer)).

double Slider::getMaximum

(

)

const

Returns the current maximum value.

See also:

setRange

double Slider::getMinimum

(

)

const

Returns the current minimum value.

See also:

setRange

double Slider::getInterval

(

)

const

Returns the current step-size for values.

See also:

setRange

double Slider::getMinValue

(

)

const

For a slider with two or three thumbs, this returns the lower of its values.

For a two-value slider, the values are controlled with getMinValue() and getMaxValue(). A slider with three values also uses the normal getValue() and setValue() methods to control the middle value.

See also:

setMinValue, getMaxValue, TwoValueHorizontal, TwoValueVertical, ThreeValueHorizontal, ThreeValueVertical

Value& Slider::getMinValueObject

(

)

For a slider with two or three thumbs, this returns the lower of its values.

You can use this Value object to connect the slider's position to external values or setters, either by taking a copy of the Value, or by using Value::referTo() to make it point to your own Value object.

See also:

Value, getMinValue, getMaxValueObject

void Slider::setMinValue	(	double	newValue,
		bool	sendUpdateMessage = true,
		bool	sendMessageSynchronously = false,
		bool	allowNudgingOfOtherValues = false
	)

For a slider with two or three thumbs, this sets the lower of its values.

This will trigger a callback to SliderListener::sliderValueChanged() for any listeners that are registered, and will synchronously call the valueChanged() method in case subclasses want to handle it.

Parameters:

	newValue	the new value to set - this will be restricted by the minimum and maximum range, and will be snapped to the nearest interval if one has been set.
	sendUpdateMessage	if false, a change to the value will not trigger a call to any SliderListeners or the valueChanged() method
	sendMessageSynchronously	if true, then a call to the SliderListeners will be made synchronously; if false, it will be asynchronous
	allowNudgingOfOtherValues	if false, this value will be restricted to being below the max value (in a two-value slider) or the mid value (in a three-value slider). If false, then if this value goes beyond those values, it will push them along with it.

See also:

getMinValue, setMaxValue, setValue

double Slider::getMaxValue

(

)

const

For a slider with two or three thumbs, this returns the higher of its values.

For a two-value slider, the values are controlled with getMinValue() and getMaxValue(). A slider with three values also uses the normal getValue() and setValue() methods to control the middle value.

See also:

getMinValue, TwoValueHorizontal, TwoValueVertical, ThreeValueHorizontal, ThreeValueVertical

Value& Slider::getMaxValueObject

(

)

For a slider with two or three thumbs, this returns the higher of its values.

You can use this Value object to connect the slider's position to external values or setters, either by taking a copy of the Value, or by using Value::referTo() to make it point to your own Value object.

See also:

Value, getMaxValue, getMinValueObject

void Slider::setMaxValue	(	double	newValue,
		bool	sendUpdateMessage = true,
		bool	sendMessageSynchronously = false,
		bool	allowNudgingOfOtherValues = false
	)

For a slider with two or three thumbs, this sets the lower of its values.

This will trigger a callback to SliderListener::sliderValueChanged() for any listeners that are registered, and will synchronously call the valueChanged() method in case subclasses want to handle it.

Parameters:

	newValue	the new value to set - this will be restricted by the minimum and maximum range, and will be snapped to the nearest interval if one has been set.
	sendUpdateMessage	if false, a change to the value will not trigger a call to any SliderListeners or the valueChanged() method
	sendMessageSynchronously	if true, then a call to the SliderListeners will be made synchronously; if false, it will be asynchronous
	allowNudgingOfOtherValues	if false, this value will be restricted to being above the min value (in a two-value slider) or the mid value (in a three-value slider). If false, then if this value goes beyond those values, it will push them along with it.

See also:

getMaxValue, setMinValue, setValue

void Slider::addListener

(

SliderListener *

listener

)

Adds a listener to be called when this slider's value changes.

void Slider::removeListener

(

SliderListener *

listener

)

Removes a previously-registered listener.

void Slider::setDoubleClickReturnValue	(	bool	isDoubleClickEnabled,
		double	valueToSetOnDoubleClick
	)

This lets you choose whether double-clicking moves the slider to a given position.

By default this is turned off, but it's handy if you want a double-click to act as a quick way of resetting a slider. Just pass in the value you want it to go to when double-clicked.

See also:

getDoubleClickReturnValue

double Slider::getDoubleClickReturnValue

(

bool &

isEnabled

)

const

Returns the values last set by setDoubleClickReturnValue() method.

Sets isEnabled to true if double-click is enabled, and returns the value that was set.

See also:

setDoubleClickReturnValue

void Slider::setChangeNotificationOnlyOnRelease

(

bool

onlyNotifyOnRelease

)

Tells the slider whether to keep sending change messages while the user is dragging the slider.

If set to true, a change message will only be sent when the user has dragged the slider and let go. If set to false (the default), then messages will be continuously sent as they drag it while the mouse button is still held down.

void Slider::setSliderSnapsToMousePosition

(

bool

shouldSnapToMouse

)

This lets you change whether the slider thumb jumps to the mouse position when you click.

By default, this is true. If it's false, then the slider moves with relative motion when you drag it.

This only applies to linear bars, and won't affect two- or three- value sliders.

void Slider::setPopupDisplayEnabled	(	bool	isEnabled,
		Component *	parentComponentToUse
	)

If enabled, this gives the slider a pop-up bubble which appears while the slider is being dragged.

This can be handy if your slider doesn't have a text-box, so that users can see the value just when they're changing it.

If you pass a component as the parentComponentToUse parameter, the pop-up bubble will be added as a child of that component when it's needed. If you pass 0, the pop-up will be placed on the desktop instead (note that it's a transparent window, so if you're using an OS that can't do transparent windows you'll have to add it to a parent component instead).

void Slider::setPopupMenuEnabled

(

bool

menuEnabled

)

If this is set to true, then right-clicking on the slider will pop-up a menu to let the user change the way it works.

By default this is turned off, but when turned on, the menu will include things like velocity sensitivity, and for rotary sliders, whether they use a linear or rotary mouse-drag to move them.

void Slider::setScrollWheelEnabled

(

bool

enabled

)

This can be used to stop the mouse scroll-wheel from moving the slider.

By default it's enabled.

int Slider::getThumbBeingDragged

(

)

const

Returns a number to indicate which thumb is currently being dragged by the mouse.

This will return 0 for the main thumb, 1 for the minimum-value thumb, 2 for the maximum-value thumb, or -1 if none is currently down.

virtual void Slider::startedDragging

(

)

[virtual]

Callback to indicate that the user is about to start dragging the slider.

See also:

SliderListener::sliderDragStarted

virtual void Slider::stoppedDragging

(

)

[virtual]

Callback to indicate that the user has just stopped dragging the slider.

See also:

SliderListener::sliderDragEnded

virtual void Slider::valueChanged

(

)

[virtual]

Callback to indicate that the user has just moved the slider.

See also:

SliderListener::sliderValueChanged

virtual int Slider::valueChanged

(

double

)

[virtual]

Callback to indicate that the user has just moved the slider.

Note - the valueChanged() method has changed its format and now no longer has any parameters. Update your code to use the new version. This version has been left here with an int as its return value to cause a syntax error if you've got existing code that uses the old version.

virtual double Slider::getValueFromText

(

const String &

text

)

[virtual]

Subclasses can override this to convert a text string to a value.

When the user enters something into the text-entry box, this method is called to convert it to a value.

The default routine just tries to convert it to a double.

See also:

getTextFromValue

virtual const String Slider::getTextFromValue

(

double

value

)

[virtual]

Turns the slider's current value into a text string.

Subclasses can override this to customise the formatting of the text-entry box.

The default implementation just turns the value into a string, using a number of decimal places based on the range interval. If a suffix string has been set using setTextValueSuffix(), this will be appended to the text.

See also:

getValueFromText

void Slider::setTextValueSuffix

(

const String &

suffix

)

Sets a suffix to append to the end of the numeric value when it's displayed as a string.

This is used by the default implementation of getTextFromValue(), and is just appended to the numeric value. For more advanced formatting, you can override getTextFromValue() and do something else.

const String Slider::getTextValueSuffix

(

)

const

Returns the suffix that was set by setTextValueSuffix().

virtual double Slider::proportionOfLengthToValue

(

double

proportion

)

[virtual]

Allows a user-defined mapping of distance along the slider to its value.

The default implementation for this performs the skewing operation that can be set up in the setSkewFactor() method. Override it if you need some kind of custom mapping instead, but make sure you also implement the inverse function in valueToProportionOfLength().

Parameters:

proportion

a value 0 to 1.0, indicating a distance along the slider

Returns:

the slider value that is represented by this position

See also:

valueToProportionOfLength

virtual double Slider::valueToProportionOfLength

(

double

value

)

[virtual]

Allows a user-defined mapping of value to the position of the slider along its length.

The default implementation for this performs the skewing operation that can be set up in the setSkewFactor() method. Override it if you need some kind of custom mapping instead, but make sure you also implement the inverse function in proportionOfLengthToValue().

Parameters:

value

a valid slider value, between the range of values specified in setRange()

Returns:

a value 0 to 1.0 indicating the distance along the slider that represents this value

See also:

proportionOfLengthToValue

float Slider::getPositionOfValue

(

double

value

)

Returns the X or Y coordinate of a value along the slider's length.

If the slider is horizontal, this will be the X coordinate of the given value, relative to the left of the slider. If it's vertical, then this will be the Y coordinate, relative to the top of the slider.

If the slider is rotary, this will throw an assertion and return 0. If the value is out-of-range, it will be constrained to the length of the slider.

virtual double Slider::snapValue	(	double	attemptedValue,
		bool	userIsDragging
	)			[virtual]

This can be overridden to allow the slider to snap to user-definable values.

If overridden, it will be called when the user tries to move the slider to a given position, and allows a subclass to sanity-check this value, possibly returning a different value to use instead.

Parameters:

	attemptedValue	the value the user is trying to enter
	userIsDragging	true if the user is dragging with the mouse; false if they are entering the value using the text box

Returns:

the value to use instead

void Slider::updateText

(

)

This can be called to force the text box to update its contents.

(Not normally needed, as this is done automatically).

bool Slider::isHorizontal

(

)

const

True if the slider moves horizontally.

bool Slider::isVertical

(

)

const

True if the slider moves vertically.

void Slider::labelTextChanged

(

Label *

)

[protected, virtual]

For internal use only.

Implements LabelListener.

void Slider::paint

(

Graphics &

g

)

[protected, virtual]

For internal use only.

Reimplemented from Component.

void Slider::resized

(

)

[protected, virtual]

For internal use only.

Reimplemented from Component.

void Slider::mouseDown

(

const MouseEvent &

e

)

[protected, virtual]

For internal use only.

Reimplemented from Component.

void Slider::mouseUp

(

const MouseEvent &

e

)

[protected, virtual]

For internal use only.

Reimplemented from Component.

void Slider::mouseDrag

(

const MouseEvent &

e

)

[protected, virtual]

For internal use only.

Reimplemented from Component.

void Slider::mouseDoubleClick

(

const MouseEvent &

e

)

[protected, virtual]

For internal use only.

Reimplemented from Component.

void Slider::mouseWheelMove	(	const MouseEvent &	e,
		float	wheelIncrementX,
		float	wheelIncrementY
	)			[protected, virtual]

For internal use only.

Reimplemented from Component.

void Slider::modifierKeysChanged

(

const ModifierKeys &

modifiers

)

[protected, virtual]

For internal use only.

Reimplemented from Component.

void Slider::buttonClicked

(

Button *

button

)

[protected, virtual]

For internal use only.

Implements ButtonListener.

void Slider::lookAndFeelChanged

(

)

[protected, virtual]

For internal use only.

Reimplemented from Component.

void Slider::enablementChanged

(

)

[protected, virtual]

For internal use only.

Reimplemented from Component.

void Slider::focusOfChildComponentChanged

(

FocusChangeType

cause

)

[protected, virtual]

For internal use only.

Reimplemented from Component.

void Slider::handleAsyncUpdate

(

)

[protected, virtual]

For internal use only.

Implements AsyncUpdater.

void Slider::colourChanged

(

)

[protected, virtual]

For internal use only.

Reimplemented from Component.

void Slider::valueChanged

(

Value &

value

)

[protected, virtual]

For internal use only.

Implements Value::Listener.

int Slider::getNumDecimalPlacesToDisplay

(

)

const throw () [protected]

Returns the best number of decimal places to use when displaying numbers.

This is calculated from the slider's interval setting.

---

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

• juce_Slider.h