Sheet

Since: BlackBerry 10.0.0

#include <bb/cascades/Sheet>

A class that represents a full-screen view as a layer.

Sheets are full-screen views that are placed as separate layers on top of the current screen context. A sheet displays a view from within the current application.

Sheets are primarily used to display a UI that's related to the creation or selection of content, often as temporary subtasks to the main navigation of the application. You can think of a sheet as representing a separate flow, or detour, from the main application flow.

Some examples of where you might use sheets include composing an email, creating a new contact, creating a meeting, or selecting content by using a picker.

A sheet includes a set of buttons at the top, which represent actions that are specific to that sheet. For example, a sheet for composing an email might include actions such as Cancel and Send. In general, a sheet should contain a cancel or back action in the upper-left corner, and a positive action (such as Send, Confirm, or OK) in the upper-right corner.

A sheet always occupies the entire screen when it is displayed, and can contain NavigationPane, TabbedPane, or Page components. A sheet can also include actions that appear on the action bar at the bottom of the sheet. An opened sheet will always be placed on top of the current screen context and will cover any previously opened sheets.

You can attach a sheet to any UIObject by using the attachedObjects property.

Defining a Sheet in C++:

Sheet* pMySheet = Sheet::create()
                  .content(Page::create())
                  .onClosed(this, SLOT(onClosedHandler())
                  .open();

Defining a Sheet in QML:

Page {
    attachedObjects: [
        Sheet {
            id: mySheet
            content: Page {
                Button {
                    text: "Close Sheet"
                    onClicked: mySheet.close()
                }
            }
        }
    ]
    actions: [
        ActionItem {
            title: "Show Sheet"
            ActionBar.placement: ActionBarPlacement.OnBar
            onTriggered: {
               mySheet.open();
            }
        }
    ]
}

Overview

Inheritance

bb::cascades::BaseObject
	bb::cascades::UIObject
		bb::cascades::AbstractDialog
			bb::cascades::Sheet

QML properties

content	: bb::cascades::AbstractPane
peekEnabled	: bool
accessibility	: bb::cascades::AbstractA11yObject [read-only]
attachedObjects	: QDeclarativeListProperty< QObject > [read-only]
objectName	: QString
opened	: bool [read-only]
parent	: QObject [read-only]

QML signals

onContentChanged	: {}
onPeekEnabledChanged	: {}
onClosed	: {}
onCreationCompleted	: {}
onObjectNameChanged	: {}
onOpened	: {}
onOpenedChanged	: {}

Properties Index

bb::cascades::AbstractPane	content
bool	peekEnabled
bb::cascades::AbstractA11yObject	accessibility [read-only]
QDeclarativeListProperty< QObject >	attachedObjects [read-only]
QString	objectName
bool	opened [read-only]
QObject	parent [read-only]

Public Functions Index

	Sheet (UIObject *parent=0)
virtual	~Sheet ()
bb::cascades::AbstractPane *	content () const
bool	isPeekEnabled () const
Q_SLOT void	resetContent ()
Q_SLOT void	resetPeekEnabled ()
Q_SLOT void	setContent (bb::cascades::AbstractPane *content)
Q_SLOT void	setPeekEnabled (bool enabled)
bb::cascades::AbstractA11yObject *	accessibility () const
Q_SLOT void	close ()
virtual bool	event (QEvent *event)
bool	isOpened () const
Q_SLOT void	open ()
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	contentChanged (bb::cascades::AbstractPane *content)
void	peekEnabledChanged (bool enabled)
void	closed ()
void	creationCompleted ()
void	objectNameChanged (const QString &objectName)
void	opened ()
void	openedChanged (bool opened)

Properties

bb::cascades::AbstractPane content

The root control for this Sheet.

This property specifies the control that appears as the root control and is displayed on this Sheet. It's often a good idea to use a Page as the root control, and add other controls to the Page.

This property is the default property of the Sheet control, so it does not need to be explicitly declared in the QML. A control added inside the Sheet will automatically be assigned to the content property.

Page {
    attachedObjects: [
        Sheet {
            Page {
                Container {
                    Button {}
                    Button {}
                }
            }
        }
    ]
}

The code sample above is equal to the following code sample:

Page {
    attachedObjects: [
        Sheet {
            content: Page {
                Container {
                    Button {}
                    Button {}
                }
            }
        }
    ]
}

Since:

BlackBerry 10.0.0

bool peekEnabled

Indicates whether peeking should be enabled in this Sheet.

This property specifies whether dragging and swiping to the right inside the current Sheet should peek. The default value is true (enabled). If enabled, the drag and swipe gestures will allow peeking in the Sheet.

When enabled, dragging or swiping to the right inside the Sheet will reveal the content directly underneath the Sheet.

Since:

BlackBerry 10.0.0

bb::cascades::AbstractA11yObject accessibility[read-only]

Defines this dialog's accessibility objects.

Accessibility objects are used by assistive technologies for people with disabilities or special needs (for example, visual impairment).

See also:

Control::accessibility

Since:

BlackBerry 10.2.0

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.

See also:

QObject::objectName().

Since:

BlackBerry 10.0.0

bool opened[read-only]

Indicates whether the dialog is currently opened.

If the value is true, the dialog is opened. If it is false, the dialog is closed.

The default value of this property is false.

The openedChanged() signal is emitted when this property changes.

Since:

BlackBerry 10.0.0

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

Sheet (
UIObject *parent)

Construct a Sheet instance.

Since:

BlackBerry 10.0.0

virtual~Sheet ()

Destructor.

bb::cascades::AbstractPane * content ()

Gets the active content of this Sheet.

Ownership will not be transferred.

Return:

The content of this Sheet.

Since:

BlackBerry 10.0.0

bool isPeekEnabled ()

Indicates whether peeking from within the current Sheet should be enabled.

Return:

true if peeking is enabled, false otherwise.

Since:

BlackBerry 10.0.0

Q_SLOT void resetContent ()

Resets the content for this Sheet.

This function resets the content for this Sheet. Content will be removed and content property set to 0. This is equivalent to setContent(0).

When this function completes, the contentChanged() signal is emitted.

Since:

BlackBerry 10.0.0

Q_SLOT void resetPeekEnabled ()

Resets the peeking behavior of the Sheet to its default state, which is disabled.

Since:

BlackBerry 10.0.0

Q_SLOT void setContent (
bb::cascades::AbstractPane *content)

Sets the content of this Sheet.

Ownership of the content will always be transferred to this Sheet. If this Sheet already has content, the old content is still owned by this Sheet and will be destroyed when this Sheet is destroyed.

If content was successfully set using this function, the contentChanged() signal is emitted.

Parameters
content	The content to set. Can be 0 to remove content (old content will still be owned by this Sheet).

Since:

BlackBerry 10.0.0

Q_SLOT void setPeekEnabled (
boolenabled)

Sets whether peeking from within the current Sheet should be enabled.

If successfully set using this function, the peekedEnabledChanged() signal is emitted.

Parameters
enabled	If true peeking is enabled, if false peeking is disabled.

Since:

BlackBerry 10.0.0

bb::cascades::AbstractA11yObject * accessibility ()

Returns the accessibility object.

Return:

The accessibility object.

Since:

BlackBerry 10.2.0

Q_SLOT void close ()

Closes the dialog.

When the dialog is closed, the value of the opened property changes to false and the closed() signal is emitted. The closed() signal might not be emitted immediately when this function is called, but could happen asynchronously at a later time.

If called when the dialog is already opening or closing, this function has no effect.

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

bool isOpened ()

Indicates whether the dialog is opened.

Return:

true if the dialog is opened, false otherwise.

Since:

BlackBerry 10.0.0

Q_SLOT void open ()

Opens the dialog.

When the dialog is opened, the value of the opened property changes to true and the opened() signal is emitted. The opened() signal might not be emitted immediately when this function is called, but could happen asynchronously at a later time.

If called when the dialog is already opening or closing, this function has no effect.

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 Sheet.

Using the builder to create a Sheet:

Sheet* mySheet = Sheet::create();

Return:

A Builder used for constructing a Sheet.

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 contentChanged (
bb::cascades::AbstractPane *content)

Emitted when the content of this Sheet has changed.

Parameters
content	The new content of this Sheet.

Since:

BlackBerry 10.0.0

void peekEnabledChanged (
boolenabled)

Emitted when peeking on the Sheet is enabled or disabled.

Parameters
enabled	If true peeking is enabled, if false peeking is disabled.

Since:

BlackBerry 10.0.0

void closed ()

Emitted when the dialog is closed.

The signal is emitted asynchronously when the dialog is completely closed after the close animation is finished.

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.

See also:

QmlDocument

Since:

BlackBerry 10.0.0

void objectNameChanged (
const QString &objectName)

This signal is emitted when the objectName property is changed.

See also:

QObject, BaseObject::objectName.

Since:

BlackBerry 10.0.0

void opened ()

Emitted when the dialog is opened.

The signal is emitted asynchronously when the dialog is completely opened after the open animation is finished.

Since:

BlackBerry 10.0.0

void openedChanged (
boolopened)

Emitted when the opened property changes its value.

Parameters
opened	If true the dialog is opened, if false the dialog is closed.

Since:

BlackBerry 10.0.0

Sheet

Overview

Inheritance

QML properties

QML signals

Properties Index

Public Functions Index

Static Public Functions Index

Protected Functions Index

Signals Index

Properties

bb::cascades::AbstractPane content

bool peekEnabled

bb::cascades::AbstractA11yObject accessibility[read-only]

QDeclarativeListProperty< QObject > attachedObjects[read-only]

QString objectName

bool opened[read-only]

QObject parent[read-only]

Public Functions

Sheet (UIObject *parent)

virtual~Sheet ()

bb::cascades::AbstractPane * content ()

bool isPeekEnabled ()

Q_SLOT void resetContent ()

Q_SLOT void resetPeekEnabled ()

Q_SLOT void setContent (bb::cascades::AbstractPane *content)

Q_SLOT void setPeekEnabled (boolenabled)

bb::cascades::AbstractA11yObject * accessibility ()

Q_SLOT void close ()

virtual bool event (QEvent *event)

bool isOpened ()

Q_SLOT void open ()

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 contentChanged (bb::cascades::AbstractPane *content)

void peekEnabledChanged (boolenabled)

void closed ()

void creationCompleted ()

void objectNameChanged (const QString &objectName)

void opened ()

void openedChanged (boolopened)

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Sheet (
UIObject *parent)

Q_SLOT void setContent (
bb::cascades::AbstractPane *content)

Q_SLOT void setPeekEnabled (
boolenabled)

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 contentChanged (
bb::cascades::AbstractPane *content)

void peekEnabledChanged (
boolenabled)

void objectNameChanged (
const QString &objectName)

void openedChanged (
boolopened)