PickerProvider

#include <bb/cascades/PickerProvider>

An interface for providing VisualNode objects as items in a Picker.

When you implement a PickerProvider, the following functions are required:

createItem(): creates an empty VisualNode object for the Picker, to be used as a picker item
updateItem(): updates an existing picker item for a particular cell in the Picker
columnCount(): gets the number of columns in the Picker

Here is how the PickerProvider can be attached to the Picker.

QML:

Picker {
    id: picker
    title: "Select items";
    onCreationCompleted: {
        picker.setPickerItemProvider(provider)
    }
    attachedObjects: [
        CustomPickerItemsProvider {
            id: provider
            columnWidthRatio: [ 2, 1 ]
        }
    ]
}

C++:

Picker *picker = Picker::create().title("Title");
PickerProvider *itemProvider = new MyPickerProvider();
picker->setPickerItemProvider(itemProvider);

Since:

BlackBerry 10.1.0

Inheritance

bb::cascades::BaseObject
	bb::cascades::PickerProvider

QML properties

columnWidthRatio	: QVariantList
objectName	: QString
parent	: QObject [read-only]

QML signals

onItemUpdatesNeeded	: {}
onColumnWidthRatioChanged	: {}
onUpdateRange	: {}
onCreationCompleted	: {}
onObjectNameChanged	: {}

Properties Index

QVariantList	columnWidthRatio
QString	objectName
QObject	parent [read-only]

Public Static Attributes Index

const int

NoBoundary

Public Functions Index

	PickerProvider (QObject *parent=0)
virtual	~PickerProvider ()
VisualNode *	createItem (Picker *pickerList, int columnIndex)=0
void	updateItem (Picker pickerList, int columnIndex, int rowIndex, VisualNode pickerItem)=0
int	columnCount () const =0
virtual void	range (int column, int lowerBoundary, int upperBoundary)
virtual QVariant	value (Picker *picker, const QList< int > &indices) const
virtual QList< int >	indicesOf (Picker *picker, const QVariant &value) const
QVariantList	columnWidthRatio ()
void	setColumnWidthRatio (const QVariantList &ratio)
void	resetColumnWidthRatio ()
void	setObjectName (const QString &name)
virtual Q_INVOKABLE QString	toDebugString () const

Protected Functions Index

Only has inherited protected functions

BaseObject (QObject *parent=0)

Signals Index

void	itemUpdatesNeeded (int column)
void	columnWidthRatioChanged (const QVariantList &ratio)
void	updateRange (int column)
void	creationCompleted ()
void	objectNameChanged (const QString &objectName)

Properties

QVariantList columnWidthRatio

Column width ratio defining widths of the Picker columns.

Since:

BlackBerry 10.1.0

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:

QObject::objectName().

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 Static Attributes

const int NoBoundary ()

Public Functions

PickerProvider (
QObject *parent)

virtual~PickerProvider ()

Destructor.

VisualNode * createItem (
Picker *pickerList,
intcolumnIndex )

Called to create a new item for the Picker.

Parameters
pickerList	The generic picker control sending the request.
columnIndex	The column which the item will be added to.

Return:

The VisualNode pointer.

Since:

BlackBerry 10.1.0

void updateItem (
Picker pickerList,
intcolumnIndex,
introwIndex,
VisualNode pickerItem )

Called to update the content for a picker item.

Parameters
pickerList	The generic picker control sending the request.
columnIndex	The column which the item is shown in.
rowIndex	The item index this node is mapped to on the server.
pickerItem	Pointer to the picker item to update.

Since:

BlackBerry 10.1.0

int columnCount ()

Gets the number of columns for this provider.

Return:

The number of columns for this provider.

Since:

BlackBerry 10.1.0

virtual void range (
intcolumn,
int lowerBoundary,
int upperBoundary )

Gets the lower and upper boundaries for the column.

Parameters
column	The column index.
lowerBoundary	The lower boundary for the column.
upperBoundary	The upper boundary for the column.

Since:

BlackBerry 10.1.0

virtualQVariant value (
Picker *picker,
const QList< int > &indices )

This method maps a list of indices to the corresponding value.

Parameters
picker	The pointer to the picker control.
indices	A list of indices to get the value for.

Return:

QVariant holding values representing the list of indices.

Since:

BlackBerry 10.1.0

virtualQList< int > indicesOf (
Picker *picker,
const QVariant &value )

Finds the picker item corresponding to the specified value.

Parameters
picker	The pointer to the picker control.
value	The value.

Return:

The list of indices corresponding to the value, or empty list if the value cannot be located

Since:

BlackBerry 10.1.0

QVariantList columnWidthRatio ()

Gets the width ratio for columns in the picker control.

Return:

The list of width ratio for columns

Since:

BlackBerry 10.1.0

void setColumnWidthRatio (
const QVariantList &ratio)

Sets width ratio for columns of picker control.

Parameters
ratio	List of int-values specifying the relative width factor.

Since:

BlackBerry 10.1.0

void resetColumnWidthRatio ()

Resets the width ratio for columns in the picker control.

Since:

BlackBerry 10.1.0

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

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

Signals

void itemUpdatesNeeded (
intcolumn)

Emitted when the Picker that uses this PickerProvider should call updateItem() for all of its cached items.

The PickerProvider implementation should typically emit this signal when an application wants to change the visual appearance of all items in a Picker.

Parameters
column	Number of column to update.

Since:

BlackBerry 10.1.0

void columnWidthRatioChanged (
const QVariantList &ratio)

Emitted when the column width ratio changes.

Parameters
ratio	The new column width ratio

Since:

BlackBerry 10.1.0

void updateRange (
intcolumn)

Emitted when the column range is changed and should be updated.

Parameters
column	The column index for which the boundaries should be updated

Since:

BlackBerry 10.1.0

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:

QmlDocument

Since:

BlackBerry 10.0.0

void objectNameChanged (
const QString &objectName)

This signal is emitted when the objectName property is changed.

See:

QObject, BaseObject::objectName.

Since:

BlackBerry 10.0.0

Inheritance

QML properties

QML signals

Properties Index

Public Static Attributes Index

Public Functions Index

Protected Functions Index

Signals Index

Properties

QVariantList columnWidthRatio

QString objectName

QObject parent[read-only]

Public Static Attributes

const int NoBoundary ()

Public Functions

PickerProvider (QObject *parent)

virtual~PickerProvider ()

VisualNode * createItem (Picker *pickerList, intcolumnIndex )

void updateItem (Picker *pickerList, intcolumnIndex, introwIndex, VisualNode *pickerItem )

int columnCount ()

virtual void range (intcolumn, int *lowerBoundary, int *upperBoundary )

virtualQVariant value (Picker *picker, const QList< int > &indices )

virtualQList< int > indicesOf (Picker *picker, const QVariant &value )

QVariantList columnWidthRatio ()

void setColumnWidthRatio (const QVariantList &ratio)

void resetColumnWidthRatio ()

void setObjectName (const QString &name)

virtual Q_INVOKABLE QString toDebugString ()

Protected Functions

BaseObject (QObject *parent)

Signals

void itemUpdatesNeeded (intcolumn)

void columnWidthRatioChanged (const QVariantList &ratio)

void updateRange (intcolumn)

void creationCompleted ()

void objectNameChanged (const QString &objectName)

PickerProvider (
QObject *parent)

VisualNode * createItem (
Picker *pickerList,
intcolumnIndex )

void updateItem (
Picker pickerList,
intcolumnIndex,
introwIndex,
VisualNode pickerItem )

virtual void range (
intcolumn,
int lowerBoundary,
int upperBoundary )

virtualQVariant value (
Picker *picker,
const QList< int > &indices )

virtualQList< int > indicesOf (
Picker *picker,
const QVariant &value )

void setColumnWidthRatio (
const QVariantList &ratio)

void setObjectName (
const QString &name)

BaseObject (
QObject *parent)

void itemUpdatesNeeded (
intcolumn)

void columnWidthRatioChanged (
const QVariantList &ratio)

void updateRange (
intcolumn)

void objectNameChanged (
const QString &objectName)