HTTP example: use std::unique_ptr instead of QScopedPointer

This allows the QFile factory there to actually return the payload in
a unique_ptr instead of falling back to a raw pointer.

The use of a unique_ptr member requires that the destructor be
out-of-line, since QFile is only forward-declared in the header
file. This is good hygiene, so do it for ProgressDialog, too.

Change-Id: Idb6ed327f9592526bb7d0d5b2cfbffe9f08f3eea
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>

examples/network/http/httpwindow.cpp

@@ -48,13 +48,14 @@
 **
 ****************************************************************************/
 
+#include "httpwindow.h"
+
+#include "ui_authenticationdialog.h"
+
 #include <QtWidgets>
 #include <QtNetwork>
 #include <QUrl>
 
-#include "httpwindow.h"
-#include "ui_authenticationdialog.h"
-
 #if QT_CONFIG(ssl)
 const char defaultUrl[] = "https://www.qt.io/";
 #else
@@ -74,6 +75,10 @@ ProgressDialog::ProgressDialog(const QUrl &url, QWidget *parent)
     setMinimumSize(QSize(400, 75));
 }
 
+ProgressDialog::~ProgressDialog()
+{
+}
+
 void ProgressDialog::networkReplyProgress(qint64 bytesRead, qint64 totalBytes)
 {
     setMaximum(totalBytes);
@@ -137,6 +142,10 @@ HttpWindow::HttpWindow(QWidget *parent)
     urlLineEdit->setFocus();
 }
 
+HttpWindow::~HttpWindow()
+{
+}
+
 void HttpWindow::startRequest(const QUrl &requestedUrl)
 {
     url = requestedUrl;
@@ -204,9 +213,9 @@ void HttpWindow::downloadFile()
     startRequest(newUrl);
 }
 
-QFile *HttpWindow::openFileForWrite(const QString &fileName)
+std::unique_ptr<QFile> HttpWindow::openFileForWrite(const QString &fileName)
 {
-    QScopedPointer<QFile> file(new QFile(fileName));
+    std::unique_ptr<QFile> file(new QFile(fileName));
     if (!file->open(QIODevice::WriteOnly)) {
         QMessageBox::information(this, tr("Error"),
                                  tr("Unable to save the file %1: %2.")
@@ -214,7 +223,7 @@ QFile *HttpWindow::openFileForWrite(const QString &fileName)
                                       file->errorString()));
         return nullptr;
     }
-    return file.take();
+    return file;
 }
 
 void HttpWindow::cancelDownload()
@@ -231,8 +240,7 @@ void HttpWindow::httpFinished()
     if (file) {
         fi.setFile(file->fileName());
         file->close();
-        delete file;
+        file.reset();
-        file = nullptr;
     }
 
     if (httpRequestAborted) {

examples/network/http/httpwindow.h

@@ -55,6 +55,8 @@
 #include <QNetworkAccessManager>
 #include <QUrl>
 
+#include <memory>
+
 QT_BEGIN_NAMESPACE
 class QFile;
 class QLabel;
@@ -72,6 +74,7 @@ class ProgressDialog : public QProgressDialog {
 
 public:
     explicit ProgressDialog(const QUrl &url, QWidget *parent = nullptr);
+    ~ProgressDialog();
 
 public slots:
    void networkReplyProgress(qint64 bytesRead, qint64 totalBytes);
@@ -83,6 +86,7 @@ class HttpWindow : public QDialog
 
 public:
     explicit HttpWindow(QWidget *parent = nullptr);
+    ~HttpWindow();
 
     void startRequest(const QUrl &requestedUrl);
 
@@ -98,7 +102,7 @@ private slots:
 #endif
 
 private:
-    QFile *openFileForWrite(const QString &fileName);
+    std::unique_ptr<QFile> openFileForWrite(const QString &fileName);
 
     QLabel *statusLabel;
     QLineEdit *urlLineEdit;
@@ -110,7 +114,7 @@ private:
     QUrl url;
     QNetworkAccessManager qnam;
     QNetworkReply *reply;
-    QFile *file;
+    std::unique_ptr<QFile> file;
     bool httpRequestAborted;
 };