Option

Since: BlackBerry 10.0.0

#include <bb/cascades/Option>

An option that can be used in a list of selectable items.

The text, description, and image properties are displayed on the screen with the intention to give visual feedback to the user regarding the option. The value property is not visible and is intended as a utility for associating the option with a certain value.

An Option is intended to be used by any control that needs to display options as selectable items in some sort of list (e.g. the DropDown control).

Not all properties in the Option control need to be visually represented by a certain control. It is up to the control that uses it to implement whatever properties it needs to and determine how they are presented.

Here's a simple QML example demonstrating how a DropDown uses options:

DropDown {
    title: "Reminder"
    enabled: true

    // image + text + description
    Option {
        imageSource: "asset:///alarm.png"
        text: "5 min"
        description: "Sets the alarm to 5 minutes"
        value: "5min"
        selected: true

        onSelectedChanged: {
            if (selected) {
                console.log("Setting alarm to 5 minutes.");
            }
        }
    }

    // text + description
    Option {
        text: "10 min"
        description: "Sets the alarm to 10 minutes"
        value: "10min"
    }

    // text only
    Option {
        text: "15 min"
        value: "15min"
    }
}

And another example in C++:

DropDown* dropDown = DropDown::create().title("DropDown");
dropDown->add(Option::create().text("Option 1"));
dropDown->add(Option::create().text("Option 2"));
dropDown->add(Option::create().text("Option 3"));

rootContainer->add(dropDown);

Overview

Inheritance

bb::cascades::BaseObject
	bb::cascades::UIObject
		bb::cascades::Option

QML properties

description	: QString
enabled	: bool
image	: bb::cascades::Image
imageSource	: QUrl
selected	: bool
text	: QString
value	: QVariant
attachedObjects	: QDeclarativeListProperty< QObject > [read-only]
objectName	: QString
parent	: QObject [read-only]

QML signals

onDescriptionChanged	: {}
onEnabledChanged	: {}
onImageChanged	: {}
onImageSourceChanged	: {}
onSelectedChanged	: {}
onTextChanged	: {}
onValueChanged	: {}
onCreationCompleted	: {}
onObjectNameChanged	: {}

Properties Index

QString	description
bool	enabled
QVariant	image
QUrl	imageSource
bool	selected
QString	text
QVariant	value
QDeclarativeListProperty< QObject >	attachedObjects [read-only]
QString	objectName
QObject	parent [read-only]

Public Functions Index

	Option (Control *parent=0)
virtual	~Option ()
const QString	description () const
Image	image () const
QUrl	imageSource () const
bool	isEnabled () const
bool	isSelected () const
Q_SLOT void	resetDescription ()
Q_SLOT void	resetEnabled ()
Q_SLOT void	resetImage ()
Q_SLOT void	resetImageSource ()
Q_SLOT void	resetSelected ()
Q_SLOT void	resetText ()
Q_SLOT void	resetValue ()
Q_SLOT void	setDescription (const QString &description)
Q_SLOT void	setEnabled (bool enabled)
Q_SLOT void	setImage (const Image &image)
Q_SLOT void	setImageSource (const QUrl &source)
Q_SLOT void	setSelected (bool selected)
Q_SLOT void	setText (const QString &text)
Q_SLOT void	setValue (const QVariant &value)
const QString	text () const
const QVariant	value () const
virtual bool	event (QEvent *event)
void	setObjectName (const QString &name)
virtual Q_INVOKABLE QString	toDebugString () const

Static Public Functions Index

Builder

create ()

Protected Functions Index

Only has inherited protected functions

	BaseObject (QObject *parent=0)
virtual void	connectNotify (const char *signal)
virtual void	disconnectNotify (const char *signal)

Signals Index

void	descriptionChanged (QString description)
void	enabledChanged (bool enabled)
void	imageChanged (const bb::cascades::Image &image)
void	imageSourceChanged (const QUrl &imageSource)
void	selectedChanged (bool selected)
void	textChanged (QString text)
void	valueChanged (QVariant value)
void	creationCompleted ()
void	objectNameChanged (const QString &objectName)

Properties

QString description

A description text set on this option.

This is the secondary textual representation of the option (the primary being the text property) and can be used for giving the user additional information. The default value is QString::null, indicating that no description is set. The descriptionChanged() signal is emitted when the description changes.

Since:

BlackBerry 10.0.0

bool enabled

Indicates whether the option is enabled.

When the option is disabled, it cannot be selected by interaction. However, the programmatic API allows selection updates even for disabled options.

If true the option is enabled, if false it is disabled. The default value is true (enabled). The enabledChanged() signal is emitted when the enabled state changes.

Since:

BlackBerry 10.0.0

QVariant image

An image set on this option.

This image can be used for giving the user additional information on this option (e.g. a contact image). The default value is a null image, indicating that no image is set. The imageChanged() signal is emitted when the image changes.

Since:

BlackBerry 10.0.0

QUrl imageSource

An image to display on the option.

If no image is set, an invalid QUrl will be returned. When changing the image source the imageSourceChanged() signal will be emitted.

Since:

BlackBerry 10.0.0

bool selected

Indicates the selected state of the option.

true if the option is selected, false otherwise. The default value is false (not selected). The selectedChanged() signal is emitted when the selected state changes.

Since:

BlackBerry 10.0.0

QString text

A title text set on this option.

This is the primary textual representation of the option and should reflect what this option is. The default value is QString::null, indicating that no title text is set. The textChanged() signal is emitted when the text changes.

Since:

BlackBerry 10.0.0

QVariant value

A value set on this option.

The value is intended to associate the option with a value and thus isn't visually represented. The value in question can be anything application specific, such as a pointer to a record set in a database. The default value is QVariant::Invalid, indicating that no value is set. The valueChanged() signal is emitted when the value changes.

Since:

BlackBerry 10.0.0

QDeclarativeListProperty< QObject > attachedObjects[read-only]

A hierarchical list of the UIObject's attached objects.

This QDeclarativeListProperty can contain any QObject. When a QObject is added to property, the UIObject takes ownership of the attached object.

This feature is typically used from QML to specify business logic object or any other shared objects for the subnodes of this UIObject. In C++ the same functionality can be achived by setting a parent of a QObject to be attached to the QObject which is going to own it.

QML usage example (MyObject is a custom class registered for QML using the qmlRegisterType() function):

Container {
    Label { text: "Title: " + myObject.title } 
    Label { text: "Subject: " + myObject.subject }
    attachedObjects: [
        MyObject { id: myObject
            title: "Hello World"
            subject: "Nice Day"
        }
    ]
}

Since:

BlackBerry 10.0.0

QString objectName

This property is overridden from QObject.

As the objectName property is overridden from the QObject class, this signal will not be emitted if setObjectName() function is called directly on QObject.

The default value of this property is QString::null.

QObject parent[read-only]

A read-only property that represents this object's parent.

The parent of an object is specified using QObject::setParent(QObject*). The purpose of the property is to expose the object's parent to QML.

This property is read-only to prevent modifications from QML, where typically the parent is declaratively set. In C++ code, the parent can be explicitly set using QObject::setParent(QObject*), or implicitly set by adding it to a visual container.

The default value of this property is 0.

Since:

BlackBerry 10.0.0

Public Functions

Option (
Control *parent)

Constructs an Option.

Parameters
parent	The parent Control of this Option. The default is 0 if you don't specify a parent. If not 0, the ownership of the constructed option will be transferred to the parent.

Since:

BlackBerry 10.0.0

virtual~Option ()

Destructor.

Since:

BlackBerry 10.0.0

const QString description ()

Returns the description text set on this option.

QString::null is returned when description text was not set.

Return:

The description text set on this option.

Since:

BlackBerry 10.0.0

Image image ()

Returns the image set on this option.

A null Image is returned when an image is not set.

Return:

The image set on this option.

Since:

BlackBerry 10.0.0

QUrl imageSource ()

Returns the image source.

Return:

The source of the displayed image.

Since:

BlackBerry 10.0.0

bool isEnabled ()

Returns the enabled state of the option (i.e.

if it is enabled or not).

Return:

true if the option is enabled, false otherwise.

Since:

BlackBerry 10.0.0

bool isSelected ()

Returns the selected state for the option.

Return:

true if this option is selected, false if it is not selected.

Since:

BlackBerry 10.0.0

Q_SLOT void resetDescription ()

Resets the description text on this option to a default value of QString::null.

The descriptionChanged() signal is emitted if the description text is changed.

Since:

BlackBerry 10.0.0

Q_SLOT void resetEnabled ()

Resets the enabled state of the option to true.

Since:

BlackBerry 10.0.0

Q_SLOT void resetImage ()

Resets the image on this option to a default value of a null Image.

The imageChanged() signal is emitted if the image is reset.

Since:

BlackBerry 10.0.0

Q_SLOT void resetImageSource ()

Resets the Image on the option to its default, meaning that no image is set.

This function emits an imageSourceChanged() signal if the currently set image source changes.

Since:

BlackBerry 10.0.0

Q_SLOT void resetSelected ()

Resets the option to the default state (not selected).

Since:

BlackBerry 10.0.0

Q_SLOT void resetText ()

Resets the text on this option to a default value of QString::null.

The textChanged() signal is emitted if the text is reset.

Since:

BlackBerry 10.0.0

Q_SLOT void resetValue ()

Resets the value of this option.

The valueChanged() signal is emitted if the value is changed.

Since:

BlackBerry 10.0.0

Q_SLOT void setDescription (
const QString &description)

Sets the description text on this option.

The descriptionChanged() signal is emitted if the description text is changed.

Parameters
description	The new description text for this option.

Since:

BlackBerry 10.0.0

Q_SLOT void setEnabled (
boolenabled)

Sets the enabled state of the option (i.e.

if it is enabled or not).

Parameters
enabled	If true the option is enabled, if false the option is disabled.

Since:

BlackBerry 10.0.0

Q_SLOT void setImage (
const Image &image)

Sets the image on this option.

The imageChanged() signal is emitted if the image is changed.

Parameters
image	The new image for this option.

Since:

BlackBerry 10.0.0

Q_SLOT void setImageSource (
const QUrl &source)

Sets the Image for the option.

An invalid QUrl indicates no image. This function emits an imageSourceChanged() signal if the currently set image source changes.

Parameters
source	The image url.

Since:

BlackBerry 10.0.0

Q_SLOT void setSelected (
boolselected)

Sets the selected state for the option.

Parameters
selected	If true this option is selected, if false this option is not selected.

Since:

BlackBerry 10.0.0

Q_SLOT void setText (
const QString &text)

Sets the new text on this option.

The textChanged() signal is emitted if the text is changed.

Parameters
text	The new text for this option.

Since:

BlackBerry 10.0.0

Q_SLOT void setValue (
const QVariant &value)

Sets the value on this option.

The valueChanged() signal is emitted if the value is changed.

Parameters
value	The new value for this option.

Since:

BlackBerry 10.0.0

const QString text ()

Returns the text set on this option.

QString::null is returned when text was not set.

Return:

The text set on this option.

Since:

BlackBerry 10.0.0

const QVariant value ()

Returns the value set on this option.

Return:

The value set on this option.

Since:

BlackBerry 10.0.0

virtual bool event (
QEvent *event)

Overloaded to implement the event mechanism in Cascades.

Warning!

If this function is overridden, it must be called by the derived class for events to work properly in Cascades.

Parameters
event	The received event.

Return:

True if the received event was recognized and processed, false otherwise.

Since:

BlackBerry 10.0.0

void setObjectName (
const QString &name)

Sets the objectName property.

Parameters
name	The new name for the object.

Since:

BlackBerry 10.0.0

virtual Q_INVOKABLE QString toDebugString ()

Returns a debug string representing this object.

Return:

A debug string for the object.

Since:

BlackBerry 10.0.0

Static Public Functions

Builder create ()

Creates and returns a builder for constructing a Option.

Using the builder to create a Option:

Option* option5 = Option::create()
    .text("option 5")
    .selected(true);

Return:

A builder used for constructing an Option.

Since:

BlackBerry 10.0.0

Protected Functions

(Only has inherited protected functions)

BaseObject (
QObject *parent)

Constructs an instance of BaseObject's subclass.

Parameters
parent	An optional parent, defaults to 0.

Since:

BlackBerry 10.0.0

virtual void connectNotify (
const char *signal)

Overloaded to implement the event mechanism in Cascades.

If this function is overridden, it must be called by the derived class for events to work properly in Cascades.

Parameters
signal	The connected signal.

Since:

BlackBerry 10.0.0

virtual void disconnectNotify (
const char *signal)

Overloaded to implement the event mechanism in Cascades.

If this function is overridden, it must be called by the derived class for events to work properly in Cascades.

Parameters
signal	The disconnected signal.

Since:

BlackBerry 10.0.0

Signals

void descriptionChanged (
QStringdescription)

Emitted when this option's description text changes.

Parameters
description	The new description string, or QString::null if changed to an empty description.

Since:

BlackBerry 10.0.0

void enabledChanged (
boolenabled)

Emitted when the enabled property on the option changes.

Parameters
enabled	If true the option is enabled, if false the option is disabled.

Since:

BlackBerry 10.0.0

void imageChanged (
const bb::cascades::Image &image,
)

Emitted when this option's image changes.

Parameters
image	The new image, or a null image if no image is shown.

Since:

BlackBerry 10.0.0

void imageSourceChanged (
const QUrl &imageSource)

Emitted when the image source changes.

Parameters
imageSource	The new image source, or an invalid QUrl if no source is set.

Since:

BlackBerry 10.0.0

void selectedChanged (
boolselected)

Emitted when the selected state changes.

Parameters
selected	The new selected state. If true this option is selected, if false this option is not selected.

Since:

BlackBerry 10.0.0

void textChanged (
QStringtext)

Emitted when this option's title text changes.

Parameters
text	The new text string, or QString::null if changed to an empty text.

Since:

BlackBerry 10.0.0

void valueChanged (
QVariantvalue)

Emitted when this option's value changes.

Parameters
value	The new value, or QString::null if changed to an empty value.

Since:

BlackBerry 10.0.0

void creationCompleted ()

This signal is emitted only when this object is instantiated as a result of loading a QML document and creating the root node, or when an object is being constructed using its builder class.

This signal is emitted only when this object is instantiated as a result of loading a QML document and creating the root node (only after the root component that caused this instantiation has completed construction), or when the object is being constructed from its builder class. This signal is emitted to indicate that the construction and initialization of the object has been completed, the properties are initialized, and any QML binding values have been assigned to the object.

This signal is not emitted when the object is constructed from C++ using the constructor. If the object is constructed using its builder class, the signal is emitted when the the builder class returns the fully constructed object.

This signal can be used when there is an activity that needs to be performed, such as a property state integrity verification after the object is instantiated from a QML document or a builder, but before control is returned to the application.

void objectNameChanged (
const QString &objectName)

This signal is emitted when the objectName property is changed.

Option

Overview

Inheritance

QML properties

QML signals

Properties Index

Public Functions Index

Static Public Functions Index

Protected Functions Index

Signals Index

Properties

QString description

bool enabled

QVariant image

QUrl imageSource

bool selected

QString text

QVariant value

QDeclarativeListProperty< QObject > attachedObjects[read-only]

QString objectName

QObject parent[read-only]

Public Functions

Option (Control *parent)

virtual~Option ()

const QString description ()

Image image ()

QUrl imageSource ()

bool isEnabled ()

bool isSelected ()

Q_SLOT void resetDescription ()

Q_SLOT void resetEnabled ()

Q_SLOT void resetImage ()

Q_SLOT void resetImageSource ()

Q_SLOT void resetSelected ()

Q_SLOT void resetText ()

Q_SLOT void resetValue ()

Q_SLOT void setDescription (const QString &description)

Q_SLOT void setEnabled (boolenabled)

Q_SLOT void setImage (const Image &image)

Q_SLOT void setImageSource (const QUrl &source)

Q_SLOT void setSelected (boolselected)

Q_SLOT void setText (const QString &text)

Q_SLOT void setValue (const QVariant &value)

const QString text ()

const QVariant value ()

virtual bool event (QEvent *event)

void setObjectName (const QString &name)

virtual Q_INVOKABLE QString toDebugString ()

Static Public Functions

Builder create ()

Protected Functions

BaseObject (QObject *parent)

virtual void connectNotify (const char *signal)

virtual void disconnectNotify (const char *signal)

Signals

void descriptionChanged (QStringdescription)

void enabledChanged (boolenabled)

void imageChanged (const bb::cascades::Image &image, )

void imageSourceChanged (const QUrl &imageSource)

void selectedChanged (boolselected)

void textChanged (QStringtext)

void valueChanged (QVariantvalue)

void creationCompleted ()

void objectNameChanged (const QString &objectName)

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Option (
Control *parent)

Q_SLOT void setDescription (
const QString &description)

Q_SLOT void setEnabled (
boolenabled)

Q_SLOT void setImage (
const Image &image)

Q_SLOT void setImageSource (
const QUrl &source)

Q_SLOT void setSelected (
boolselected)

Q_SLOT void setText (
const QString &text)

Q_SLOT void setValue (
const QVariant &value)

virtual bool event (
QEvent *event)

void setObjectName (
const QString &name)

BaseObject (
QObject *parent)

virtual void connectNotify (
const char *signal)

virtual void disconnectNotify (
const char *signal)

void descriptionChanged (
QStringdescription)

void enabledChanged (
boolenabled)

void imageChanged (
const bb::cascades::Image &image,
)

void imageSourceChanged (
const QUrl &imageSource)

void selectedChanged (
boolselected)

void textChanged (
QStringtext)

void valueChanged (
QVariantvalue)

void objectNameChanged (
const QString &objectName)