Display camera preview using Qt Mobility
| ID | Creation date | 28th Mar 2010 | |
| Platform | S60 5th Edition | Tested on devices | Nokia N97 Mini |
| Category | Qt | Subcategory | Qt Mobility API |
| Keywords (APIs, classes, methods, functions): QCamera, QVideoWidget |
Warning: Camera API has been removed from Mobility. It was in the tech preview and maybe it will be added again later on.
Tip: Read this article before moving forward: Setting up environment for Qt Mobility API
Contents |
Overview
Display Camera Preview on Widget using Qt Mobility APIs
Project configuration file (.Pro file)
- Add the Qt Mobility project configuration option in the .Pro file as shown below
CONFIG += mobility
MOBILITY += multimedia
symbian:TARGET.CAPABILITY = UserEnvironment
Header File
#include <qcamera.h>
#include <qvideowidget.h>
#include <qstackedwidget.h>
class CameraApp : public QWidget
{
Q_OBJECT
public:
CameraApp(QWidget* parent = 0);
~CameraApp();
public slots:
void error(QCamera::Error);
private:
void initCamera();
private:
QStackedWidget* m_stackedWidget;
QCamera* m_camera;
QVideoWidget* m_videoWidget;
};
Source File
#include <qmessagebox.h>
#include <qgridlayout.h>
CameraApp::CameraApp(QWidget *parent) :
QWidget(parent), m_camera(0)
{
QGridLayout* layout = new QGridLayout;
layout->setSpacing(0);
layout->setMargin(0);
m_videoWidget = new QVideoWidget();
QPalette black(Qt::black);
m_stackedWidget = new QStackedWidget();
m_stackedWidget->setPalette(black);
m_stackedWidget->addWidget(m_videoWidget);
m_stackedWidget->setCurrentIndex(0);
layout->addWidget(m_stackedWidget);
setLayout(layout);
InitCamera();
}
void CameraApp::initCamera() {
QByteArray cameraDevice = QCamera::availableDevices()[0];
m_camera = new QCamera(cameraDevice);
connect(m_camera, SIGNAL(error(QCamera::Error)), this, SLOT(error(QCamera::Error)));
m_camera->setFocusMode(QCamera::AutoFocus);
m_videoWidget->setMediaObject(m_camera);
m_videoWidget->setAspectRatioMode(QVideoWidget::KeepAspectRatio);
if (m_camera->state() == QCamera::ActiveState) {
m_camera->stop();
}
m_camera->start();
}
void CameraApp::error(QCamera::Error e) {
switch (e) {
case QCamera::CameraError: {
QMessageBox::warning(this, "Camera error", "General camera error");
break;
}
case QCamera::NotReadyToCaptureError: {
QMessageBox::warning(this, "Camera error", "Camera not ready to capture image");
break;
}
case QCamera::InvalidRequestError: {
QMessageBox::warning(this, "Camera error", "Invalid request");
break;
}
case QCamera::ServiceMissingError: {
QMessageBox::warning(this, "Camera error", "Service missing");
break;
}
case QCamera::NotSupportedFeatureError: {
QMessageBox::warning(this, "Camera error", "Not supported feature");
break;
}
default:
break;
};
}
Classes
QCamera
QVideoWidget
