Nokia NFC 1.1.6 - Day1

1

Manikantan Krishnamurthy Technical Manager

Nokia, SEAP

NFC and Qt Mobility for NFC

© 2011 Nokia Nokia NFC Development v. 1.1.6

NFC Forum and the NFC Forum logo are trademarks of the Near Field Communication Forum.

What is Near Field Communication (NFC)?

Simplifies local communication into an easy and intuitive gesture

Based on and extends RFID. Operates on 13.56 MHz frequency. Transmits up to 424Kbits/sec

Open-platform technology that is being standardized in the NFC Forum

Short-range radio technology that enables communication between devices that touch/momentarily held close together

Operates over a distance of just a few centimetres, up to 10cm (Nokia: best to touch)

Typical applications are in contactless transactions, social and local interactions

Extensive experience in NFC globally • First to bring commercial NFC devices to market

• More than 80 trials and pilots globally (AT&T, O2, Citibank, Maxis, Visa, MasterCard)

• First to deploy commercial services (Austria, Malaysia, India)

3

2005 2007 2008 P6/2011

Nokia 3220 Nokia 5140i Nokia 6131 NFC

Nokia 6212 classic

Nokia C7 Symbian Anna

4

Key NFC Experiences Sharing

Transfer content between any two NFC devices

Peer to peer mode

Pairing

Connect easily with other NFC devices

Reader mode

Service Initiation

Start a service or an application

Reader/writer mode

Secure NFC

Mobile device is a credit card and travel card

Card emulation mode

5

What can NFC do for your App? Add value (NFC enhanced apps) vs. Create new value (NFC centric apps)

NFC Application Types

• NFC Centric Apps

– The application will only work

on NFC devices.

– Publisher makes sure that

the application is only

available to NFC enabled

devices

• NFC Enhanced Apps

– Offer NFC feature when

available on device

– Check for presence of NFC

feature and adapt the user

experience or...

– Make 2 versions of the

application

6

7

NFC Enhanced App – Angry Birds Magic

Comes with 20 levels

• First 5 levels available for play

• Remaining 15 levels are locked

Unlock 5 levels at a time with NFC interaction

• Touch your C7 with another C7 or certain NFC tags

NFC Centric App – Poken • Poken is a social networking app that enables

exchanging social business cards with a touch

– Create your social identity with multiple profiles

– Auto-friending on social networks such as FB,

LinkedIn…

– Combines activity feeds

• Collect, classify and share NFC tag info

• View contacts and collection in a dynamic

timeline

8

9

NFC Basics

http://www.nfc-forum.org/specs/




Near Field Communication

• International standard

– Interface and protocol for simple wireless interconnection of

closely coupled devices operating at 13.56 MHz

• Spec overview

– Omits specific bit / byte encodings,

details and alternatives

– Gives high-level overview of the concepts!

10

The 'N' Logo is a trademark of the NFC Forum, Inc. in the United States and in other countries.

NFC Forum Standard Overview *

11

Applications

RF Layer – ISO 18092 + ISO 14443 A/B + FeliCa

Mode Switching

Card Emulation

Smart Card capability for mobile devices

Peer-2-Peer

– LLCP (Logical Link Control Protocol)

– NFCIP

Reader / Writer

– RTD (Record Type Definition)

– NDEF (NFC Data Exchange format)

Protocol bindings (IP, OBEX, etc)

Tag Type 1, 2, 3, 4

* Figure adapted from NFC Forum Specification (www.nfc-forum.org)

12

Operating Modes

• Reader/writer: when reader is polling for a

tag

• Peer to Peer: communicate with another

NFC device (share information)

• Card Emulation*: where the NFC device

acts as a card (e.g. credit card or gift card)

Reader /writer

Peer to Peer

Base Band

NFC Antenna

Services & adaptation

NFC Interfaces

NFC Applications

NFC Controller Card Emulation*

* not supported in Symbian Anna

13

Tag & Reader NFC-based communication between two devices is possible when one device acts as a reader/writer and the other as a tag.

Tag (Initiator)

• Simple, thin device containing antenna and

small amount of memory

• Passive, powered by magnetic field that can

be picked up by Target

• Can be Read-Only/Rewritable/Writable once

Reader (Target)

• Active device generating radio signals to

communicate with tags

• Powers the passive tag when the two are

engaged in the passive mode

14

Discover Services and Content

Touch a hot spot on a smart poster with your device

What is a smart poster or object?

• Any object which contains readable NFC tags

Poster Magazine page Gadgets

What can NFC tags contain? * • Business card

• An SMS message

• Website URL

• Bluetooth information

• Code to launch an app

* Additional content types are possible as well.

Interactive, immersive and immediate

15

NFC tags vs. Barcodes

– No NFC HW required – Easily recognizable

– Inconvenient (camera, focus, take picture) – Large visual impact on product – Very limited data storage – Limited use cases (no app launch, BT pairing) – Write-only

– Works by touching, instant – Design can be merged with product – Larger data storage possible – Multiple use cases (app launch, BT pairing) – Re-writable (if desired)

– Requires NFC HW – New to consumers

16

Developing NFC apps in Qt

Target NFC devices

17 © 2011 Nokia Nokia NFC Development v. 1.1.6

Nokia 600

Nokia 700

Nokia 701

N9

Nokia 603

Following slides are for Qt SDK 1.1.3

24 © 2011 Nokia Nokia NFC Development v. 1.1.6 August 16, 2011

Qt NFC Development • Requirements

– Qt SDK 1.1.3 – Contains: Qt 4.7.3, Qt Mobility 1.1.3 – Contains: Qt 4.7.4, Qt Mobility 1.2.0

– Nokia Ovi Suite 3.x

– Symbian – Windows 7 (or XP) – Nokia C7 with Symbian Anna (for development) – Simulator

– MeeGo – Nokia N9 – Install Qt SDK’s experimental MeeGo Harmattan target


Device Setup • Install Symbian Belle (Windows Start menu)

– Qt 4.7.4

– WebKit for Qt 4.7.4

– CODA

– Qt mobility1.2.0

• One-click install from Windows requires Ovi Suite

– Alternative: copy files to device mass memory, install on

the device using Applications → Office → File mgr.



Qt Mobility

Mobility 1.0

Bearer Management API Contacts Location Messaging Multimedia Publish and Subscribe Service Framework Sensors System Information Versit

Mobility 1.1

Camera Document Gallery Feedback Landmarks Maps/Navigation Organizer Service Framework – Out of process

Mobility 1.2 – develop now, deploy later this year

Connectivity (Bluetooth, NFC)

Qt Mobility 1.2 NFC • Interact with

– NFC Forum tags

– Target detection

– NDEF message handlers

– Reading and writing NDEF messages

– Send tag specific commands

– Master / slave communication

– NFC Forum devices

– LLCP Sockets

– Peer to peer communication



API Overview* QNearFieldManager

Detects and filters targets

QLlcpServer Listen for new server socket connections.

QNearFieldTarget Query properties,

read/write messages, send commands or

establish a client socket

QNdefMessage Collection of 0 or more

records

QNdefRecord Access to NDEF data.

Subclasses for handling specific details.

QLlcpSocket Read / write data. For

server & client sockets.

* Not a class diagram, but explains sequential usage order

Generic NFC

Tag access

Peer to peer

Qt NFC Source Code • Qt Mobility is Open Source

– How does a method work? How to make best use

of it? Take a look at the source code!

• Download complete source package

– http://labs.qt.nokia.com/2011/04/12/qt-mobility-

1-2-beta-package-released/

→ qt-mobility-symbian-opensource-1.2.0-beta1.zip

– Find implementation in:

C:\QtMobility\src\connectivity\nfc


http://labs.qt.nokia.com/2011/04/12/qt-mobility-1-2-beta-package-released/













31

NFC Corkboards


Tasks

– Extend Qt SDK example with NFC:

Touch tag to create note

– Qt Quick based UI

– C++ based NFC

– Integrate C++ with QML

https://projects.developer.nokia.com/nfccorkboards



Importing the Example • From Qt Creator

– Open project:

C:\QtSDK\Examples\4.7\declarative\toys\corkboards\corkboards.pro


Choosing Targets • If you are using SDK 1.1.2,

• Select our new Qt 4.7.3 for Symbian^3 with QtM1.2b target


Choosing Targets • If you are using SDK 1.1.3,

• Select Qt Simulator


Test! With Simulator

• Select Qt Simulator

• Play to compile and deploy!



App Overview

main.cpp

Application startup

Loads and shows corkboards.qml

corkboards.qml

UI definition

Defines data model and view

Day.qml

Delegate for drawing the UI for a single day

Interaction for notes

ndefmanager.cpp/.h

NFC Tag discovery and reading

We will add this:

in: corkboards.qml id: list

in: corkboards.qml id: flickable

in: Day.qml


Model, View & Delegate

ListModel

Defines free-form list data source

Container for ListElement definitions

ListView

Shows data from a model in a list

Horizontal or vertical

Delegate

Template defining each item instantiated by the view

Add Connectivity

• Edit the Qt project file (corkboards.pro)

– Uncomment & add mobility component: connectivity

– Add LocalServices Capability


CONFIG += mobility

MOBILITY += connectivity

symbian:TARGET.CAPABILITY += NetworkServices LocalServices

Allows Internet access Allows NFC

Good to Know: Symbian Security *

1. Determine the required security / privacy related features

– Most common:

2. Define the capabilities in the Qt project file (.pro)


* Qt apps are native apps; therefore, the security model of the target operating system applies.

Feature Capability

Internet access, telephony, messaging NetworkServices

Access location (GPS, etc.) Location

Camera, record audio UserEnvironment

Contacts, Calendar ReadUserData / WriteUserData

Bluetooth, NFC LocalServices

IMEI, model name, battery status ReadDeviceData

(See: developer.nokia.com/Community/Wiki/Capabilities)

symbian:TARGET.CAPABILITY += Location LocalServices

Basic Capabilities

Extended Capabilities

http://www.developer.nokia.com/Community/Wiki/Capabilities

V#-Filename.ppt / 10/25/2011 © 2009 Nokia 40 Access

Capability

Certified Signed

Symbian Signed for

Nokia

Sa

les v

ersio

n

Sa

les v

ersio

n

1 week 1 week

LocalServices

ReadUserData

WriteUserData

NetworkServices

UserEnvironment

Location

SwEvent

ProtServ

TrustedUI

PowerMgmt

SurroundingsDD

ReadDeviceData

WriteDeviceData

CommDD

DiskAdmin

MultimediaDD

NetworkControl

AllFiles

DRM

TCB

Lead-time

Note Test house

Tested Test house

Tested

Express Signed

Sa

les v

ersio

n

Immediate Developer

tested

Open Signed

with PublisherID

For te

sting

Immediate

Certify on PC

Open Signed

without PublisherID

For te

sting

Immediate

Upload SIS

For

testin

g &

sa

les

ve

rsion

User Grantable

Immediate Developer

Tested

Device

Manufacturer

approval

Good to Know: Symbian Security

3. Get the right certificate during development


No / Basic Capabilities Extended Capabilities

Sign up for Ovi Publish account (€1) publish.ovi.com

Request development certificate (free) developer.nokia.com/Distribute/Packaging_and_signing.xhtml

Sign your app (Qt Creator build settings)

Test on your develoment device(s)

Use auto-generated self signed certificate (default, no action required)

http://publish.ovi.com/

http://www.developer.nokia.com/Distribute/Packaging_and_signing.xhtml

Good to Know: Symbian Security

4. Publish


No / Basic Capabilities Extended Capabilities

Sign up for Ovi Publish account (€1) publish.ovi.com

Request development certificate (free) developer.nokia.com/Distribute/Packaging_and_signing.xhtml

Sign & package your Qt app with the Smart Installer (Qt Creator build settings)

Publish to the Nokia Store Need Certified Signed capabilities? developer.nokia.com/Community/Wiki/Capabilities -> Purchase a Publisher ID ($200 / year) Submit to Certified Signed process @ www.symbiansigned.com

http://publish.ovi.com/


http://www.developer.nokia.com/Community/Wiki/Capabilities

http://www.symbiansigned.com/

NdefManager

• New C++ class

– Right-click the project

→ Add New ...

→ C++ Class

– Class name: NdefManager

– Base class: QObject


Qt Meta-Object System

• C++ extended with QObject

– Introspection: meta-information at runtime

– Inter-object communication: signals & slots

– Parent / Child hierarchy: easier memory

management


Include

• Headers, define member variable


#include <qnearfieldmanager.h>

#include <qndeffilter.h>

#include <qnearfieldtarget.h>

#include <qndefmessage.h>

#include <qndefrecord.h>

#include <qndefnfcurirecord.h>

#include <QUrl>

#include <QDebug> // we will test first!

QTM_USE_NAMESPACE // Use Qt Mobility namespace

[...]

private:

QNearFieldManager *nfcManager;

ndefmanager.h


Start Waiting NdefManager::NdefManager(QObject *parent) : QObject(parent)

{

// NdefManager (this) is the parent; will automatically delete nfcManager

nfcManager = new QNearFieldManager(this);

nfcManager->setTargetAccessModes(QNearFieldManager::NdefReadTargetAccess);

// React only to Uri records (NfcRtd, "U")

QNdefFilter filter;

filter.appendRecord<QNdefNfcUriRecord>();

// Registers message handler with criteria - Uri

nfcManager->registerNdefMessageHandler(filter,

this, SLOT(targetDetected(QNdefMessage,QNearFieldTarget*)));

// Get notified when the tag gets out of range

connect(nfcManager, SIGNAL(targetLost(QNearFieldTarget*)),

this, SLOT(targetLost(QNearFieldTarget*)));

}

ndefmanager.cpp

Signals & Slots • Signal

– Emitted when a particular event occurs (e.g., clicked())

– Qt objects: predefined signals

– Also create your own signals

• Slot

– Function called in response to a signal

– Qt objects: predefined slots (e.g., quit())

– Also create your own slots

• Connection signals slots established by developer,

handled by Qt framework


Signals & Slots • Type safe

– Signal signature must match signature of receiving slot

– (Slot might also have shorter signature and ignore the rest of the

arguments)

• Loosely coupled

– Emitter doesn’t know or care which slots receive signal

– Information encapsulation

• Integrated, independent components

– Slots are normal C++ member functions

– Don’t know if signals are connected to them


Lost & Found

• Methods to handle lost & found tags = Slots

• Tip

– Alt + Enter, and Qt Creator writes the .cpp method definition!


private slots:

void targetDetected(const QNdefMessage &message,

QNearFieldTarget *target);

void targetLost(QNearFieldTarget *target);

ndefmanager.h

React

• New target: write debug output to console for now

• Target out of range: delayed object delete


void NdefManager::targetDetected(const QNdefMessage &message,

QNearFieldTarget *target)

{

qDebug() << "Uri Target detected!";

}

ndefmanager.cpp

void NdefManager::targetLost(QNearFieldTarget *target)

{

target->deleteLater();

}

ndefmanager.cpp

Register C++ with QML

• Make your C++ class available in QML

– QML Name: NdefManager

– QML Library: Nfc 1.0


#include <QtDeclarative>

#include "ndefmanager.h"

int main(int argc, char *argv[]) {

QApplication app(argc, argv);

qmlRegisterType<NdefManager>("Nfc", 1, 0, "NdefManager");

[...]

}

main.cpp

NdefManager in QML

• Import module

• Create Instance


import Nfc 1.0

corkboards.qml

NdefManager {

id: ndefManager

}

corkboards.qml

Test! #2

• Run the app

• Touch a URI formatted NDEF tag

• Observe the Application Output


Parse Tag & Emit Contents

• Revisit and extend the target detection slot


void NdefManager::targetDetected(const QNdefMessage &message,

QNearFieldTarget *target) {

qDebug() << "Uri Target detected!";

// Go through all records in the message

foreach (const QNdefRecord &record, message) {

// Check type again, just to make sure

if (record.isRecordType<QNdefNfcUriRecord>()) {

// Convert to the specialized URI record class

QNdefNfcUriRecord uriRecord(record);

// Emit a signal with the URI

emit nfcReadTagUri(uriRecord.uri());

}

}

}

ndefmanager.cpp

Define the Signal

• Signals have no implementation

– They represent information, not a method to execute


signals:

void nfcReadTagUri(const QUrl& nfcTagUri);

ndefmanager.h

Create new Notes

• Handle our new signal

– on<signal> : <javascript code>

– Get current corkboard page → append new notes element →

key: “noteText”, value: URI from NDEF message


NdefManager {

id: ndefManager

onNfcReadTagUri:

list.get(flickable.currentIndex).notes.append({"noteText":nfcTagUri})

}

corkboards.qml

Test! #3

• Touch Uri-formatted NDEF NFC tags to create notes on the

current page!


58

Interactive NFC Corkboards


Tasks

– Extend previous example

– React to any kind of tags

– Write tags by pressing the red flag

while touching a tag





Overview – Before QNdefFilter filter;


nfcManager->registerNdefMessageHandler(filter, this,

SLOT(targetDetected(QNdefMessage,QNearFieldTarget*)));

void targetDetected(const QNdefMessage &message,

QNearFieldTarget *target);

Signal is only emitted when a tag containing all records defined in the filter are found

Register NDEF filters and detect targets

The slot directly gets the NDEF message


Overview – After connect(nfcManager, SIGNAL(targetDetected(QNearFieldTarget*)),

this, SLOT(targetDetected(QNearFieldTarget*)));

nfcManager->startTargetDetection();

void targetDetected(QNearFieldTarget *target) {

const bool hasNdefMessage = target->hasNdefMessage();

if (hasNdefMessage) {

connect(target, SIGNAL(ndefMessageRead(QNdefMessage)),

this, SLOT(ndefMessageRead(QNdefMessage)));

target->readNdefMessages();

}

}

Signals is emitted for every target that is detected

Detect any kind of targets

void NdefManager::ndefMessageRead(const QNdefMessage &message) ;

Another signal is emitted when reading the message from the target is finished

React to all targets

• Generic target detection instead of listening to specific tag

message(s)

– Remove previous targetDetected() with two parameters


public slots:

void nfcWriteTag(const QString& nfcTagText); // New

private slots:

void targetDetected(QNearFieldTarget *target); // Modified from prev.

void ndefMessageRead(const QNdefMessage &message); // New

private:

QNearFieldTarget *cachedTarget; // New

ndefmanager.h


Start Generic Target Detection NdefManager::NdefManager(QObject *parent) : QObject(parent)

{

// [...]

// React only to Uri records (NfcRtd, "U")

QNdefFilter filter;


nfcManager->registerNdefMessageHandler(filter,

this, SLOT(targetDetected(QNdefMessage,QNearFieldTarget*)));




connect(nfcManager, SIGNAL(targetDetected(QNearFieldTarget*)),



}

ndefmanager.cpp

Read NDEF Message

• Detected a target? Read its message.


void NdefManager::targetDetected(QNearFieldTarget *target)

{

qDebug() << "Target detected!";

const bool hasNdefMessage = target->hasNdefMessage();

if (hasNdefMessage) {

connect(target, SIGNAL(ndefMessageRead(QNdefMessage)),

this, SLOT(ndefMessageRead(QNdefMessage)));

target->readNdefMessages();

}

// Cache target to member variable for writing

cachedTarget = target;

}

ndefmanager.cpp

Target Lost

• Set cached target to NULL


void NdefManager::targetLost(QNearFieldTarget *target) {

cachedTarget = NULL; // New


}

ndefmanager.cpp

Parse NDEF Message

• Same code as before, different method


void NdefManager::ndefMessageRead(const QNdefMessage &message) {

// Go through all records in the message

foreach (const QNdefRecord &record, message) {

// Check type

if (record.isRecordType<QNdefNfcUriRecord>()) {

// Convert to the specialized URI record class

QNdefNfcUriRecord uriRecord(record);

// Emit a signal with the URI

emit nfcReadTagUri(uriRecord.uri());

}

}

}

ndefmanager.cpp

66 © 2011 Nokia Nokia NFC Development v. 1.1.6 August 16, 2011 Andreas Jakl

Write URI Ndef Message void NdefManager::nfcWriteTag(const QString &nfcTagText) {

// The device currently has a target in reach

if (cachedTarget) {

// Convert text to a URI, adding missing http:// if necessary

QUrl convertedUrl = QUrl::fromUserInput(nfcTagText);

// Check if it is a valid URL

if (convertedUrl.isValid() && nfcTagText.contains('.')) {

QNdefMessage message;

// Create a URI NDEF record

QNdefNfcUriRecord uriRecord;

uriRecord.setUri(convertedUrl);

message.append(uriRecord);

qDebug() << "Writing URI ...";

// Write NDEF message to the tag

cachedTarget->writeNdefMessages(QList<QNdefMessage>() << message);

} else {

qDebug() << "No valid URI";

}

} else {

qDebug() << "No cached target available";

}

}

ndefmanager.cpp


Extend UI with Write Button Image {

id: writeButton

source: "NfcFlag.png"

rotation: -8 // Note image itself is rotated

anchors { bottom: parent.bottom; right:parent.right }

MouseArea {

anchors.fill: parent

onClicked: ndefManager.nfcWriteTag(myText.text)

}

}

Day.qml, between lines 122 / 123 (below MouseArea with id: mouse)

NfcFlag.png <project dir>\qml\

Test! • Touch a tag, at the same time press the NFC flag of a note

– Writes the note text to the tag

– Remember to enter a valid URI!


The extended solution on Nokia Developer Projects additionally handles text tags and potential

errors.




69

NFC Corkboards


Task

– Adding autostart feature




Auto start feature • Create an xml file with the format given below ( for Symbian^3 )


<?xml version="1.0" encoding="UTF-8"?>

<SFW version="1.1">

<service> <name>%APPNAME%</name>

<ipcaddress>%APPNAME%</ipcaddress>

<description>NFC NDEF message handler for %APPNAME%</description>

<interface>

<name>com.nokia.qtmobility.nfc.NdefMessageHandler</name>

<version>1.0</version>

<description>NFC NDEF message handler for %APPNAME%</description>

<capabilities></capabilities>

<customproperty key="datatype">%DATATYPE%</customproperty>

</interface>

</service>

</SFW>

Auto start feature • Recommended to name the xml file after the application package name

• XML file needs to be installed in the correct location. The following needs to be

added into the .pro file


symbian {

ndefhandler.sources = %APPNAME%.xml

ndefhandler.path = /private/2002AC7F/import/

DEPLOYMENT += ndefhandler

}

Auto start feature • Make sure that the application calls registerNdefMessageHandler()


NdefManager::NdefManager(QObject *parent) : QObject(parent)

{






// Add this line below

nfcManager->registerNdefMessageHandler(this,

SLOT(targetMessageDetected(QNdefMessage,QNearFieldTarget*)));


}

ndefmanager.cpp

Auto start feature


private slots:

void targetMessageDetected(const QNdefMessage &message,

QNearFieldTarget *target );

ndefmanager.h

• Remember to add the targetMessageDetected() in the header/cpp files

void NdefManager::targetMessageDetected(const QNdefMessage &message,

QNearFieldTarget *target)

{

qDebug() << "Target detected!";

ndefMessageRead(message);

}

ndefmanager.cpp

74

NFC Chat


Tasks

– Develop an NFC chat from scratch

– NFC Peer to Peer mode

– LLCP Protocol (server & client sockets)

– Qt Quick UI

https://projects.developer.nokia.com/nfcchat




App Overview

main.cpp

Application startup

Loads and shows main.qml

main.qml

UI definition

Defines data model and view

nfcpeertopeer.cpp/.h

Target discovery

NFC Peer to peer sockets (client & server)

New Project (SDK 1.1.2)

• Qt Quick Application

– Name: NfcChat

– Targets: only

Qt 4.7.3 w/ QtM 1.2

(uncheck Qt 4.7.3 for Desktop)

– Accept defaults for the rest


New Project (SDK 1.1.3) • Qt Quick Application

– Name: NfcChat

– Application Type: Qt Quick

Application Components

for Symbian

– Targets: only

Qt 4.7.4 for Symbian Belle

– Accept defaults for the rest 77 © 2011 Nokia Nokia NFC Development v. 1.1.6

Add Connectivity

• Edit the Qt project file (nfcchat.pro)

– Uncomment & add mobility component: connectivity

– Add LocalServices Capability


CONFIG += mobility

MOBILITY += connectivity

symbian:TARGET.CAPABILITY += NetworkServices LocalServices

Allows Internet access Allows NFC

UI Design • Delete existing main.qml and MainPage.qml

• Add a new QML page main.qml

• create the followings:

• Button (Image + mousearea) – set id as “sendButton”

• TextEdit – set id as “sendTextEdit”

• List View – set id as “messageView”

• List Model – set id as “messageModel”


Solution: (main.qml) import QtQuick 1.0

Rectangle {

id: rectangle1

width: 360

height: 360

Image {

id: sendButton

x: 291

anchors.right: parent.right

anchors.rightMargin: 0

anchors.top: parent.top

anchors.topMargin: 0

source: "NfcButton.png"

MouseArea {

id: mouse_area1

anchors.fill: parent

} }

// continue next page

}


Solution: (main.qml) TextEdit {

id: sendTextEdit

width: 80

height: 20

text: "Hello NFC"

anchors.left: parent.left

anchors.leftMargin: 0

anchors.top: parent.top


font.pixelSize: 10

}

ListModel { id:messageModel }

// continue next page


Solution: (main.qml) ListView {

id: messageView

model: messageModel

delegate: Text {text: chatMessage }

anchors.right: parent.right

anchors.rightMargin: 0

anchors.left: parent.left

anchors.leftMargin: 0

anchors.bottom: parent.bottom

anchors.bottomMargin: 0

anchors.top: sendButton.bottom


}


NfcPeerToPeer

• Go to the “Edit” view

• New C++ class

– Right-click the project

→ Add New ...

→ C++ Class

– Class name: NfcPeerToPeer

– Base class: QObject


Include

• Headers, define member variable


#include <qnearfieldmanager.h>

#include <qllcpserver.h>

#include <qllcpsocket.h>

QTM_USE_NAMESPACE // Use Qt Mobility namespace

[...]

private:

QLatin1String nfcUri;

QNearFieldManager *nfcManager;

QLlcpServer *nfcServer;

QLlcpSocket *nfcClientSocket;

QLlcpSocket *nfcServerSocket;

nfcpeertopeer.h

Search for Targets

• Save own unique service Uri and start target detection


NfcPeerToPeer::NfcPeerToPeer(QObject *parent) :

QObject(parent), nfcUri("urn:nfc:sn:com.nokia.nfcchat")

{

nfcManager = new QNearFieldManager(this);





// Only detect other NFC devices. Leave the phone to handle NFC tags.

nfcManager->startTargetDetection(QNearFieldTarget::NfcForumDevice);

}

nfcpeertopeer.cpp

Signals & Slots

• Handle targets

• Emit chat messages to the UI


private slots:

void targetDetected(QNearFieldTarget *target);

void targetLost(QNearFieldTarget *target);

nfcpeertopeer.h

signals:

void chatMessage(const QString& nfcClientMessage);

nfcpeertopeer.h

React

• New target: emit info message

• Target out of range: emit message & delayed object delete


void NfcPeerToPeer::targetDetected(QNearFieldTarget *target)

{

emit chatMessage("Target detected");

}

nfcpeertopeer.cpp

void NfcPeerToPeer::targetLost(QNearFieldTarget *target)

{


emit chatMessage("Target lost");

}

nfcpeertopeer.cpp

Register C++ with QML

• Make your C++ class available in QML

– QML Name: NfcPeerToPeer

– QML Library: NfcPeerToPeer 1.0


#include <QtDeclarative>

#include "nfcpeertopeer.h"

int main(int argc, char *argv[]) {

QApplication app(argc, argv);

qmlRegisterType<NfcPeerToPeer>("NfcPeerToPeer", 1, 0, "NfcPeerToPeer");

[...]

}

main.cpp

NfcPeerToPeer in QML • Import module

• Update the list model when a NFC chat message arrives


import NfcPeerToPeer 1.0

main.qml

NfcPeerToPeer {

id: nfcPeerToPeer

onChatMessage: {

messageModel.append( {"chatMessage": nfcClientMessage} )

}

}

ListModel { id: messageModel }

ListView { model: messageModel

delegate: Text { text: chatMessage }

// [...]

}

main.qml

Test!

• Run the app on two phones

– Switch phones in the Run Settings

• Touch both phones

– Admire how they detect each other!


Note: NFC app cannot be deploy on C7 with Symbian Anna at this moment With SDK 1.1.3 .

https://bugreports.qt.nokia.com/browse/QTMOBILITY-1835?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel






Test in simulator!


NFC LLCP Server Socket

• Define slots for new server connections & sending text

• Listen for new server connections


NfcPeerToPeer::NfcPeerToPeer(QObject *parent)

// [...]

nfcServer = new QLlcpServer(this);

connect(nfcServer, SIGNAL(newConnection()),

this, SLOT(handleNewConnection()));

nfcServer->listen(nfcUri);

}

nfcpeertopeer.cpp

public slots:

void sendText(const QString& text);

private slots:

void handleNewConnection();

nfcpeertopeer.h

Connections & Sending

• Create a socket for a new server connection

• Slot to send chat messages over the server socket


void NfcPeerToPeer::sendText(const QString& text) {

if (nfcServerSocket && nfcServerSocket->isOpen()) {

nfcServerSocket->write(text.toUtf8());

emit chatMessage("Message sent");

}

}

nfcpeertopeer.cpp

void NfcPeerToPeer::handleNewConnection() {

if (nfcServerSocket) { nfcServerSocket->deleteLater(); }

nfcServerSocket = nfcServer->nextPendingConnection();

}

nfcpeertopeer.cpp

Sending Chat Messages

• Call the sendText() slot in MouseArea’s onClicked handler


onClicked: nfcPeerToPeer.sendText(sendTextEdit.text)

main.qml

NFC LLCP Client Socket

• Define slot to read incoming text

• Create the client socket (to be connected to NFC targets)


NfcPeerToPeer::NfcPeerToPeer(QObject *parent)

// [...]

nfcClientSocket = new QLlcpSocket(this);

connect(nfcClientSocket, SIGNAL(readyRead()),

this, SLOT(readText()));

}

nfcpeertopeer.cpp

private slots:

void readText();

nfcpeertopeer.h

Connections & Reading • Connect the socket to a target in targetDetected()

• Read text from the socket and emit a signal

• Cleanup in targetLost()


void NfcPeerToPeer::readText() {

QByteArray rawData = nfcClientSocket->readAll();

QString data = QString::fromUtf8(rawData.constData(), rawData.size());

emit chatMessage(data);

}

nfcpeertopeer.cpp

nfcClientSocket->connectToService(target, nfcUri);

nfcpeertopeer.cpp

nfcClientSocket->disconnectFromService();

nfcpeertopeer.cpp

Test! #2

• Touch upper back of two phones

– While touching, press the send button


The extended solution on Nokia Developer Projects includes cached text sending and

error handling and is based on Qt Quick Components.

Note: if installing the solution, uninstall your own app first to avoid a name conflict..


Note: NFC app cannot be deploy on C7 with Symbian Anna at this moment With SDK 1.1.3 . Click on the link to view details









Nokia Store intake for Qt apps • 27 Models

• Compatible with Qt 4.7 / QML

• Symbian^3: N8, E7, C7, C6-01, C7 Astound, E6, X7 and Oro

• S60 5th Edition: X6, C6-00, C5-03, N97, N97 Mini, 5800, 5530, 5250, 5235, 5233, 5230, 5228

(does not support Qt Quick Components)

• Nokia N9

• Nokia N900 with PR 1.3 later

• Compatible with Qt 4.6 (Qt mobility 1.0)

• All of the above

• S60 3rd Edition: E72, E71, E66, E63 and E52

• Check here for the updated list: http://www.developer.nokia.com/Distribute/Packaging_and_signing.xhtml





Where to find help? • http://www.developer.nokia.com/Community/Wiki/About_NFC

• Qt SDK – Help, examples

• Discussion boards, wikis – Nokia Developer: http://developer.nokia.com/

– Qt Developer Network: http://developer.qt.nokia.com/

• e-Learning materials – http://qt.nokia.com/developer/learning/online/training/

– http://qt.nokia.com/services-partners/qt-in-education/qt-in-education-course-material

• Community – http://www.qtcentre.org/

102

http://developer.nokia.com/

http://developer.qt.nokia.com/

http://qt.nokia.com/developer/learning/online/training/

http://qt.nokia.com/services-partners/qt-in-education/qt-in-education-course-material















http://www.qtcentre.org/

103

Qt Books Beginning Nokia Apps Development Ray Rischpater, Daniel Zucker. Apress. Complete end-to-end story of developing for Symbian and MeeGo with Qt (Quick) and HTML 5. Status: Qt 4.7, December 2010

C++ GUI Programming with Qt 4 (2nd edition) Jasmin Blanchette, Mark Summerfield. Prentice Hall. Official book for generic Qt development (no mobile). Good for looking things up or for enhancing your knowledge, average for learning from scratch. Status: Qt 4.3, 2008

Foundations of Qt Development Johan Thelin. Apress. More in-depth and technically oriented explanation of Qt – different approach to many other books. Generic Qt, no mobile. Status: 2007

(some recommendations)

Nokia Certified Qt Developer • Official accreditation for individual developers

– Confirms your development skills in Qt

– Become more attractive in the job market!

– Qt Essentials exam: 50 multiple choice questions, 60 minutes

– Qt Advanced exams: widgets and C++

104

Nokia Developer Champion & Qt Ambassador

• Active community member?

– Be even more involved, improve your network and get rewarded!

– Nokia Developer Champion

http://www.developer.nokia.com/Community/Champions/

– Qt Ambassador

http://qt.nokia.com/qt-in-use/ambassadors/qtambassador/

105








Universities • Qt is a good way to teach software development

– Instant results to motivate attendees

– Graphical tools make entry easier

– Flexible system, extensible with own libraries

– … and still standard C++!

• University support

– Free Qt course materials under Creative Commons (PPT and OpenOffice)

http://qt.nokia.com/learning/education/course-materials

– Nokia Developer University support

http://www.developer.nokia.com/Developer_Programs/Nokia_Developer_for_uni

versities/

106





http://www.developer.nokia.com/Developer_Programs/Nokia_Developer_for_universities/



Your Feedback Counts! • Not happy with the way something works? Found a bug?

– Submit your Qt bug report or suggestion to:

http://bugreports.qt.nokia.com/

– Unsure about what to include? The guide is here:

http://developer.qt.nokia.com/wiki/ReportingBugsInQt

– Found a bug somewhere outside of Qt?

Report it here:

http://www.developer.nokia.com/Support/

– Also go to the above URL to buy a

commercial support ticket if needed!

107

http://bugreports.qt.nokia.com/

http://developer.qt.nokia.com/wiki/ReportingBugsInQt

http://www.developer.nokia.com/Support/

108

Thank You.


Documents

Nokia NFC 1.1.6 - Day1