Camera example: Brush up to C++11

Use Qt 5 signal/slot syntax, range based for, member initialization.
Add message for captured images and fix some minor issues.

Task-number: QTBUG-60627
Change-Id: I1011fc95d928a9d2edaad16120acb0dc41f987d9
Reviewed-by: Christian Stromme <christian.stromme@qt.io>

8 files changed, 55 insertions, 53 deletions

diff --git a/examples/multimediawidgets/camera/camera.cpp b/examples/multimediawidgets/camera/camera.cpp
index 2a1af875d..7a9955b01 100644
--- a/examples/multimediawidgets/camera/camera.cpp
+++ b/examples/multimediawidgets/camera/camera.cpp
@@ -58,12 +58,7 @@ Q_DECLARE_METATYPE(QCameraInfo)
 
 Camera::Camera(QWidget *parent) :
     QMainWindow(parent),
-    ui(new Ui::Camera),
-    camera(0),
-    imageCapture(0),
-    mediaRecorder(0),
-    isCapturingImage(false),
-    applicationExiting(false)
+    ui(new Ui::Camera)
 {
     ui->setupUi(this);
 
@@ -71,7 +66,8 @@ Camera::Camera(QWidget *parent) :
 
     QActionGroup *videoDevicesGroup = new QActionGroup(this);
     videoDevicesGroup->setExclusive(true);
-    foreach (const QCameraInfo &cameraInfo, QCameraInfo::availableCameras()) {
+    const QList<QCameraInfo> availableCameras = QCameraInfo::availableCameras();
+    for (const QCameraInfo &cameraInfo : availableCameras) {
         QAction *videoDeviceAction = new QAction(cameraInfo.description(), videoDevicesGroup);
         videoDeviceAction->setCheckable(true);
         videoDeviceAction->setData(QVariant::fromValue(cameraInfo));
@@ -81,8 +77,8 @@ Camera::Camera(QWidget *parent) :
         ui->menuDevices->addAction(videoDeviceAction);
     }
 
-    connect(videoDevicesGroup, SIGNAL(triggered(QAction*)), SLOT(updateCameraDevice(QAction*)));
-    connect(ui->captureWidget, SIGNAL(currentChanged(int)), SLOT(updateCaptureMode()));
+    connect(videoDevicesGroup, &QActionGroup::triggered, this, &Camera::updateCameraDevice);
+    connect(ui->captureWidget, &QTabWidget::currentChanged, this, &Camera::updateCaptureMode);
 
     setCamera(QCameraInfo::defaultCamera());
 }
@@ -102,20 +98,21 @@ void Camera::setCamera(const QCameraInfo &cameraInfo)
 
     camera = new QCamera(cameraInfo);
 
-    connect(camera, SIGNAL(stateChanged(QCamera::State)), this, SLOT(updateCameraState(QCamera::State)));
-    connect(camera, SIGNAL(error(QCamera::Error)), this, SLOT(displayCameraError()));
+    connect(camera, &QCamera::stateChanged, this, &Camera::updateCameraState);
+    connect(camera, QOverload<QCamera::Error>::of(&QCamera::error), this, &Camera::displayCameraError);
 
     mediaRecorder = new QMediaRecorder(camera);
-    connect(mediaRecorder, SIGNAL(stateChanged(QMediaRecorder::State)), this, SLOT(updateRecorderState(QMediaRecorder::State)));
+    connect(mediaRecorder, &QMediaRecorder::stateChanged, this, &Camera::updateRecorderState);
 
     imageCapture = new QCameraImageCapture(camera);
 
-    connect(mediaRecorder, SIGNAL(durationChanged(qint64)), this, SLOT(updateRecordTime()));
-    connect(mediaRecorder, SIGNAL(error(QMediaRecorder::Error)), this, SLOT(displayRecorderError()));
+    connect(mediaRecorder, &QMediaRecorder::durationChanged, this, &Camera::updateRecordTime);
+    connect(mediaRecorder, QOverload<QMediaRecorder::Error>::of(&QMediaRecorder::error),
+            this, &Camera::displayRecorderError);
 
     mediaRecorder->setMetaData(QMediaMetaData::Title, QVariant(QLatin1String("Test Title")));
 
-    connect(ui->exposureCompensation, SIGNAL(valueChanged(int)), SLOT(setExposureCompensation(int)));
+    connect(ui->exposureCompensation, &QAbstractSlider::valueChanged, this, &Camera::setExposureCompensation);
 
     camera->setViewfinder(ui->viewfinder);
 
@@ -123,14 +120,14 @@ void Camera::setCamera(const QCameraInfo &cameraInfo)
     updateLockStatus(camera->lockStatus(), QCamera::UserRequest);
     updateRecorderState(mediaRecorder->state());
 
-    connect(imageCapture, SIGNAL(readyForCaptureChanged(bool)), this, SLOT(readyForCapture(bool)));
-    connect(imageCapture, SIGNAL(imageCaptured(int,QImage)), this, SLOT(processCapturedImage(int,QImage)));
-    connect(imageCapture, SIGNAL(imageSaved(int,QString)), this, SLOT(imageSaved(int,QString)));
-    connect(imageCapture, SIGNAL(error(int,QCameraImageCapture::Error,QString)), this,
-            SLOT(displayCaptureError(int,QCameraImageCapture::Error,QString)));
+    connect(imageCapture, &QCameraImageCapture::readyForCaptureChanged, this, &Camera::readyForCapture);
+    connect(imageCapture, &QCameraImageCapture::imageCaptured, this, &Camera::processCapturedImage);
+    connect(imageCapture, &QCameraImageCapture::imageSaved, this, &Camera::imageSaved);
+    connect(imageCapture, QOverload<int, QCameraImageCapture::Error, const QString &>::of(&QCameraImageCapture::error),
+            this, &Camera::displayCaptureError);
 
-    connect(camera, SIGNAL(lockStatusChanged(QCamera::LockStatus,QCamera::LockChangeReason)),
-            this, SLOT(updateLockStatus(QCamera::LockStatus,QCamera::LockChangeReason)));
+    connect(camera, QOverload<QCamera::LockStatus, QCamera::LockChangeReason>::of(&QCamera::lockStatusChanged),
+            this, &Camera::updateLockStatus);
 
     ui->captureWidget->setTabEnabled(0, (camera->isCaptureModeSupported(QCamera::CaptureStillImage)));
     ui->captureWidget->setTabEnabled(1, (camera->isCaptureModeSupported(QCamera::CaptureVideo)));
@@ -197,7 +194,7 @@ void Camera::processCapturedImage(int requestId, const QImage& img)
 
     // Display captured image for 4 seconds.
     displayCapturedImage();
-    QTimer::singleShot(4000, this, SLOT(displayViewfinder()));
+    QTimer::singleShot(4000, this, &Camera::displayViewfinder);
 }
 
 void Camera::configureCaptureSettings()
@@ -217,6 +214,7 @@ void Camera::configureCaptureSettings()
 void Camera::configureVideoSettings()
 {
     VideoSettings settingsDialog(mediaRecorder);
+    settingsDialog.setWindowFlags(settingsDialog.windowFlags() & ~Qt::WindowContextHelpButtonHint);
 
     settingsDialog.setAudioSettings(audioSettings);
     settingsDialog.setVideoSettings(videoSettings);
@@ -237,6 +235,7 @@ void Camera::configureVideoSettings()
 void Camera::configureImageSettings()
 {
     ImageSettings settingsDialog(imageCapture);
+    settingsDialog.setWindowFlags(settingsDialog.windowFlags() & ~Qt::WindowContextHelpButtonHint);
 
     settingsDialog.setImageSettings(imageSettings);
 
@@ -385,12 +384,12 @@ void Camera::setExposureCompensation(int index)
 
 void Camera::displayRecorderError()
 {
-    QMessageBox::warning(this, tr("Capture error"), mediaRecorder->errorString());
+    QMessageBox::warning(this, tr("Capture Error"), mediaRecorder->errorString());
 }
 
 void Camera::displayCameraError()
 {
-    QMessageBox::warning(this, tr("Camera error"), camera->errorString());
+    QMessageBox::warning(this, tr("Camera Error"), camera->errorString());
 }
 
 void Camera::updateCameraDevice(QAction *action)
@@ -416,7 +415,7 @@ void Camera::readyForCapture(bool ready)
 void Camera::imageSaved(int id, const QString &fileName)
 {
     Q_UNUSED(id);
-    Q_UNUSED(fileName);
+    ui->statusbar->showMessage(tr("Captured \"%1\"").arg(QDir::toNativeSeparators(fileName)));
 
     isCapturingImage = false;
     if (applicationExiting)
diff --git a/examples/multimediawidgets/camera/camera.h b/examples/multimediawidgets/camera/camera.h
index 3db1347b6..45a73176c 100644
--- a/examples/multimediawidgets/camera/camera.h
+++ b/examples/multimediawidgets/camera/camera.h
@@ -56,7 +56,7 @@ class Camera : public QMainWindow
     Q_OBJECT
 
 public:
-    Camera(QWidget *parent = 0);
+    explicit Camera(QWidget *parent = nullptr);
     ~Camera();
 
 private slots:
@@ -107,16 +107,16 @@ protected:
 private:
     Ui::Camera *ui;
 
-    QCamera *camera;
-    QCameraImageCapture *imageCapture;
-    QMediaRecorder* mediaRecorder;
+    QCamera *camera = nullptr;
+    QCameraImageCapture *imageCapture = nullptr;
+    QMediaRecorder* mediaRecorder = nullptr;
 
     QImageEncoderSettings imageSettings;
     QAudioEncoderSettings audioSettings;
     QVideoEncoderSettings videoSettings;
     QString videoContainerFormat;
-    bool isCapturingImage;
-    bool applicationExiting;
+    bool isCapturingImage = false;
+    bool applicationExiting = false;
 };
 
 #endif
diff --git a/examples/multimediawidgets/camera/imagesettings.cpp b/examples/multimediawidgets/camera/imagesettings.cpp
index 55441b4e3..658176369 100644
--- a/examples/multimediawidgets/camera/imagesettings.cpp
+++ b/examples/multimediawidgets/camera/imagesettings.cpp
@@ -56,16 +56,17 @@ ImageSettings::ImageSettings(QCameraImageCapture *imageCapture, QWidget *parent)
 
     //image codecs
     ui->imageCodecBox->addItem(tr("Default image format"), QVariant(QString()));
-    foreach(const QString &codecName, imagecapture->supportedImageCodecs()) {
+    const QStringList supportedImageCodecs = imagecapture->supportedImageCodecs();
+    for (const QString &codecName : supportedImageCodecs) {
         QString description = imagecapture->imageCodecDescription(codecName);
-        ui->imageCodecBox->addItem(codecName+": "+description, QVariant(codecName));
+        ui->imageCodecBox->addItem(codecName + ": " + description, QVariant(codecName));
     }
 
     ui->imageQualitySlider->setRange(0, int(QMultimedia::VeryHighQuality));
 
     ui->imageResolutionBox->addItem(tr("Default Resolution"));
-    QList<QSize> supportedResolutions = imagecapture->supportedResolutions();
-    foreach(const QSize &resolution, supportedResolutions) {
+    const QList<QSize> supportedResolutions = imagecapture->supportedResolutions();
+    for (const QSize &resolution : supportedResolutions) {
         ui->imageResolutionBox->addItem(QString("%1x%2").arg(resolution.width()).arg(resolution.height()),
                                         QVariant(resolution));
     }
diff --git a/examples/multimediawidgets/camera/imagesettings.h b/examples/multimediawidgets/camera/imagesettings.h
index 31afbd2f5..5e23ef8e4 100644
--- a/examples/multimediawidgets/camera/imagesettings.h
+++ b/examples/multimediawidgets/camera/imagesettings.h
@@ -56,7 +56,7 @@ class ImageSettings : public QDialog
     Q_OBJECT
 
 public:
-    ImageSettings(QCameraImageCapture *imageCapture, QWidget *parent = 0);
+    explicit ImageSettings(QCameraImageCapture *imageCapture, QWidget *parent = nullptr);
     ~ImageSettings();
 
     QAudioEncoderSettings audioSettings() const;
diff --git a/examples/multimediawidgets/camera/imagesettings.ui b/examples/multimediawidgets/camera/imagesettings.ui
index f790c770d..8c59ca01d 100644
--- a/examples/multimediawidgets/camera/imagesettings.ui
+++ b/examples/multimediawidgets/camera/imagesettings.ui
@@ -11,7 +11,7 @@
    </rect>
   </property>
   <property name="windowTitle">
-   <string>Dialog</string>
+   <string>Image Settings</string>
   </property>
   <layout class="QGridLayout" name="gridLayout">
    <item row="0" column="0">
diff --git a/examples/multimediawidgets/camera/videosettings.cpp b/examples/multimediawidgets/camera/videosettings.cpp
index 3e0c2afd0..38e8e476b 100644
--- a/examples/multimediawidgets/camera/videosettings.cpp
+++ b/examples/multimediawidgets/camera/videosettings.cpp
@@ -56,47 +56,49 @@ VideoSettings::VideoSettings(QMediaRecorder *mediaRecorder, QWidget *parent) :
 
     //audio codecs
     ui->audioCodecBox->addItem(tr("Default audio codec"), QVariant(QString()));
-    foreach (const QString &codecName, mediaRecorder->supportedAudioCodecs()) {
+    const QStringList supportedAudioCodecs =  mediaRecorder->supportedAudioCodecs();
+    for (const QString &codecName : supportedAudioCodecs) {
         QString description = mediaRecorder->audioCodecDescription(codecName);
-        ui->audioCodecBox->addItem(codecName+": "+description, QVariant(codecName));
+        ui->audioCodecBox->addItem(codecName + ": " + description, QVariant(codecName));
     }
 
     //sample rate:
-    foreach (int sampleRate, mediaRecorder->supportedAudioSampleRates()) {
+    const QList<int>supportedAudioSampleRates = mediaRecorder->supportedAudioSampleRates();
+    for (int sampleRate : supportedAudioSampleRates)
         ui->audioSampleRateBox->addItem(QString::number(sampleRate), QVariant(sampleRate));
-    }
 
     ui->audioQualitySlider->setRange(0, int(QMultimedia::VeryHighQuality));
 
     //video codecs
     ui->videoCodecBox->addItem(tr("Default video codec"), QVariant(QString()));
-    foreach (const QString &codecName, mediaRecorder->supportedVideoCodecs()) {
+    const QStringList supportedVideoCodecs = mediaRecorder->supportedVideoCodecs();
+    for (const QString &codecName : supportedVideoCodecs) {
         QString description = mediaRecorder->videoCodecDescription(codecName);
-        ui->videoCodecBox->addItem(codecName+": "+description, QVariant(codecName));
+        ui->videoCodecBox->addItem(codecName + ": " + description, QVariant(codecName));
     }
 
     ui->videoQualitySlider->setRange(0, int(QMultimedia::VeryHighQuality));
 
 
     ui->videoResolutionBox->addItem(tr("Default"));
-    QList<QSize> supportedResolutions = mediaRecorder->supportedResolutions();
-    foreach (const QSize &resolution, supportedResolutions) {
+    const QList<QSize> supportedResolutions = mediaRecorder->supportedResolutions();
+    for (const QSize &resolution : supportedResolutions) {
         ui->videoResolutionBox->addItem(QString("%1x%2").arg(resolution.width()).arg(resolution.height()),
                                         QVariant(resolution));
     }
 
     ui->videoFramerateBox->addItem(tr("Default"));
-    QList<qreal> supportedFrameRates = mediaRecorder->supportedFrameRates();
-    qreal rate;
-    foreach (rate, supportedFrameRates) {
+    const QList<qreal> supportedFrameRates = mediaRecorder->supportedFrameRates();
+    for (qreal rate : supportedFrameRates) {
         QString rateString = QString("%1").arg(rate, 0, 'f', 2);
         ui->videoFramerateBox->addItem(rateString, QVariant(rate));
     }
 
     //containers
     ui->containerFormatBox->addItem(tr("Default container"), QVariant(QString()));
-    foreach (const QString &format, mediaRecorder->supportedContainers()) {
-        ui->containerFormatBox->addItem(format+":"+mediaRecorder->containerDescription(format),
+    const QStringList formats = mediaRecorder->supportedContainers();
+    for (const QString &format : formats) {
+        ui->containerFormatBox->addItem(format + ": " + mediaRecorder->containerDescription(format),
                                         QVariant(format));
     }
 }
diff --git a/examples/multimediawidgets/camera/videosettings.h b/examples/multimediawidgets/camera/videosettings.h
index c4a05face..1751025fb 100644
--- a/examples/multimediawidgets/camera/videosettings.h
+++ b/examples/multimediawidgets/camera/videosettings.h
@@ -56,7 +56,7 @@ class VideoSettings : public QDialog
     Q_OBJECT
 
 public:
-    VideoSettings(QMediaRecorder *mediaRecorder, QWidget *parent = 0);
+    explicit VideoSettings(QMediaRecorder *mediaRecorder, QWidget *parent = nullptr);
     ~VideoSettings();
 
     QAudioEncoderSettings audioSettings() const;
diff --git a/examples/multimediawidgets/camera/videosettings.ui b/examples/multimediawidgets/camera/videosettings.ui
index f6aa004c5..940b7db7a 100644
--- a/examples/multimediawidgets/camera/videosettings.ui
+++ b/examples/multimediawidgets/camera/videosettings.ui
@@ -11,7 +11,7 @@
    </rect>
   </property>
   <property name="windowTitle">
-   <string>Dialog</string>
+   <string>Video Settings</string>
   </property>
   <layout class="QGridLayout" name="gridLayout_4">
    <item row="0" column="0">