BrightnessEffect

Since: BlackBerry 10.3.1

#include <bb/cascades/BrightnessEffect>

A brightness effect that can brighten or darken images and other controls.

Here are some examples of how icons appear using different levels of brightness.

Sets of icons that use different brightness values.

And here's an example of how to attach the effect to a control:

        ImageView {
            imageSource: "asset:///ca_camera_inactive.png"
            effects: [
                BrightnessEffect {
                    enabled: true
                    brightness: brightSlider.value
                }
            ]
        }


Overview

QML properties

brightness: float
attachedObjects: QDeclarativeListProperty< QObject > [read-only]Inherited
enabled: boolInherited
objectName: QStringInherited
parent: QObject [read-only]Inherited
ui: bb::cascades::UIConfig [read-only]Inherited

QML signals

Properties Index

floatbrightness
QDeclarativeListProperty< QObject >attachedObjects [read-only]Inherited
boolenabledInherited
QStringobjectNameInherited
QObjectparent [read-only]Inherited
bb::cascades::UIConfigui [read-only]Inherited

Public Functions Index

BrightnessEffect (VisualNode *parent=0)
virtual ~BrightnessEffect ()
floatbrightness () const
Q_SLOT voidresetBrightness ()
Q_SLOT voidsetBrightness (float brightness)
virtual boolevent (QEvent *event)Inherited
boolisEnabled () const Inherited
Q_SLOT voidresetEnabled ()Inherited
Q_SLOT voidsetEnabled (bool enabled)Inherited
voidsetObjectName (const QString &name)Inherited
virtual Q_INVOKABLE QStringtoDebugString () const Inherited
Q_INVOKABLE bb::cascades::UIConfig *ui () const Inherited

Static Public Functions Index

Buildercreate ()

Protected Functions Index

Only has inherited protected functions

BaseObject (QObject *parent=0)Inherited
virtual voidconnectNotify (const char *signal)Inherited
virtual voiddisconnectNotify (const char *signal)Inherited

Signals Index

voidbrightnessChanged (float brightness)
voidcreationCompleted ()Inherited
voidenabledChanged (bool enabled)Inherited
voidobjectNameChanged (const QString &objectName)Inherited

Properties

float brightness

The brightness of the BrightnessEffect.

Since:

BlackBerry 10.3.1

QDeclarativeListProperty< QObject > attachedObjectsInherited[read-only]

A hierarchical list of the UIObject's attached objects.

Since:

BlackBerry 10.0.0

bool enabledInherited

Whether the effect is enabled out or not.

Since:

BlackBerry 10.3.1

QString objectNameInherited

This property is overridden from QObject.

See also:

QObject::objectName().

Since:

BlackBerry 10.0.0

QObject parentInherited[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

bb::cascades::UIConfig uiInherited[read-only]

An object that gives access to unit conversion routines.

QML use:
        // Size using design units
        Container {
            preferredWidth: ui.du(12)
            preferredHeight: ui.du(5)
        }

        // Size using design units, snap to whole pixels
        Container {
            preferredWidth: ui.sdu(13.5)
            preferredHeight: ui.sdu(7.5)
        }

        // Size using absolute pixel values
        Container {
            preferredWidth: ui.px(150)
            preferredHeight: ui.px(50)
        }
C++ use:
Container *container1 = Container::create().background(Color::Red);
UIConfig *ui = container1->ui();
container1->setPreferredWidth(ui->du(12));
container1->setPreferredHeight(ui->du(5));

Container *container2 = Container::create().background(Color::Green);
container2->setPreferredWidth(ui->sdu(13.5));
container2->setPreferredHeight(ui->sdu(7.5));

Container *container3 = Container::create().background(Color::Blue);
container3->setPreferredWidth(ui->px(150));
container3->setPreferredHeight(ui->sdu(50));
Since:

Blackberry 10.3.0

Public Functions

BrightnessEffect (

Constructs a BrightnessEffect object.

When you add a brightness effect to a control using VisualNode::addEffect(), the control assumes ownership of this instance unless it was previously added to a different control, in which case ownership stays with the original control.

Parameters
parent

The parent visual node. This parameter is optional and defaults to 0 if not specified. When the effect is assigned to a node, this value is updated.

virtual~BrightnessEffect ()

Destructor.

float brightness ()

Gets the brightness for the BrightnessEffect.

Return:

The brightness of the BrightnessEffect. Valid values range from -150.0 (all pixels darkened to be black or transparent) to 150.0 (all pixels brightened to be white or transparent).

Since:

BlackBerry 10.3.1

Q_SLOT void resetBrightness ()

Resets the brightness for this BrightnessEffect to 0.0.

Since:

BlackBerry 10.3.1

Q_SLOT void setBrightness (
  • floatbrightness)

Sets the brightness level for the BrightnessEffect.

Parameters
brightness

The brightness to use on this BrightnessEffect.

Since:

BlackBerry 10.3.1

virtual bool event (Inherited

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

bool isEnabled ()Inherited

Specifies whether the effect is enabled or not.

If the enabled property is set to false, the effect is not rendered. The default enabled value is true.

Since:

BlackBerry 10.3.1

Return:

true if the effect is enabled, false otherwise.

Since:

BlackBerry 10.3.1

Q_SLOT void resetEnabled ()Inherited

Resets the effect to be enabled.

If the enabled property is set to false, the effect is not rendered. The default enabled value is true.

Since:

BlackBerry 10.3.1

Since:

BlackBerry 10.3.1

Q_SLOT void setEnabled (
  • boolenabled)
Inherited

Sets whether the effect should be enabled or not.

If the enabled property is set to false, the effect is not rendered. The default enabled value is true.

Since:

BlackBerry 10.3.1

Parameters
enabled

true to make the effect enabled, false otherwise.

Since:

BlackBerry 10.3.1

void setObjectName (Inherited

Sets the objectName property.

Parameters
name

The new name for the object.

Since:

BlackBerry 10.0.0

virtual Q_INVOKABLE QString toDebugString ()Inherited

Returns a debug string representing this object.

Return:

A debug string for the object.

Since:

BlackBerry 10.0.0

Q_INVOKABLE bb::cascades::UIConfig * ui ()Inherited

Returns the UIConfig for this ui object.

The UIConfig can be used to perform unit conversions from design units (du) and snapped design units (sdu) to pixels.

Ownership remains with Cascades.

C++ use:
Container *container1 = Container::create().background(Color::Red);
UIConfig *ui = container1->ui();
container1->setPreferredWidth(ui->du(12));
container1->setPreferredHeight(ui->du(5));

Container *container2 = Container::create().background(Color::Green);
container2->setPreferredWidth(ui->sdu(13.5));
container2->setPreferredHeight(ui->sdu(7.5));

Container *container3 = Container::create().background(Color::Blue);
container3->setPreferredWidth(ui->px(150));
container3->setPreferredHeight(ui->sdu(50));
Return:

The UIConfig for this ui object.

Since:

BlackBerry 10.3.0

Static Public Functions

Builder create ()

Creates and returns a builder for constructing an BrightnessEffect.

Using the builder to create an BrightnessEffect object:
 BrightnessEffect* pBrightnessEffect = BrightnessEffect::create()
Return:

A builder used for constructing an BrightnessEffect object.

Protected Functions

(Only has inherited protected functions)

BaseObject (Inherited

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)
Inherited

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)
Inherited

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 brightnessChanged (
  • floatbrightness)

Emitted when the brightness level changes.

Parameters
brightness

The new brightness level for the BrightnessEffect.

Since:

BlackBerry 10.3.1

void creationCompleted ()Inherited

Emitted 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 indicates 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.

See also:

QmlDocument

Since:

BlackBerry 10.0.0

void enabledChanged (
  • boolenabled)
Inherited

Emitted when the enabled property of the effect is changed.

If the enabled property is set to false, the effect is not rendered. The default enabled value is true.

Since:

BlackBerry 10.3.1

Parameters
enabled

The new enabled value for the effect.

Since:

BlackBerry 10.3.1

void objectNameChanged (Inherited

This signal is emitted when the objectName property is changed.

Since:

BlackBerry 10.0.0

Last modified: 2015-03-26



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