Brush up the DOM bookmarks example

- Use modern string literals (use QStringLiteral instead of
  QLatin1StringView for strings that go into the DOM API).
- Use mime types in the file dialog handling
- Streamline code
- Remove mentions of SAX
- Use per class includes
- Do not use QObject::tr()
- Use the configure system instead of QT_NO... defines
- Fix some doc text typos

Complements 3dd3268ded4dd74c64d7ec726fd534375ab9f018.

Task-number: QTBUG-111974
Change-Id: If0dc7b61e729d0a71f37743efc9b82e285d3f451
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
(cherry picked from commit 3a553507a134bee1562d34ebbf786a053d36fc05)

examples/xml/dombookmarks/doc/src/dombookmarks.qdoc

@@ -20,7 +20,7 @@
 
     The XbelTree class has functions for reading and writing to the filesystem.
     It inherits from the QTreeWidget class, contains the model for the
-    dispalying of the bookmarks, and allows it to be edited.
+    displaying of the bookmarks, and allows it to be edited.
 
     \snippet dombookmarks/xbeltree.h 0
 
@@ -68,23 +68,22 @@
 
     \snippet dombookmarks/mainwindow.cpp 0
 
-    The \c createMenus() function poulates the menus and sets keyboard
+    The \c createMenus() function populates the menus and sets keyboard
     shortcuts.
 
     \snippet dombookmarks/mainwindow.cpp 4
 
     The \c open() function enables the user to open an XBEL file using
-    QFileDialog::getOpenFileName(). A warning message is displayed along
+    QFileDialog. A warning message is displayed along
     with the \c fileName and \c errorString if the file cannot be read or
     if there is a parse error. If it succeeds it calls \c XbelTree::read().
 
     \snippet dombookmarks/mainwindow.cpp 1
 
     The \c saveAs() function displays a QFileDialog, prompting the user for
-    a \c fileName using QFileDialog::getSaveFileName(). Similar to the
+    a \c fileName. Similar to the \c open() function, this function also
-    \c open() function, this function also displays a warning message if
+    displays a warning message if the file cannot be written to. If this
-    the file cannot be written to. IF this succeeds it calls \c
+    succeeds it calls \c XbelTree::write().
-    XbelTree::write().
 
     \snippet dombookmarks/mainwindow.cpp 2
 

examples/xml/dombookmarks/mainwindow.cpp

@@ -1,11 +1,20 @@
 // Copyright (C) 2016 The Qt Company Ltd.
 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
 
-#include <QtWidgets>
-
 #include "mainwindow.h"
 #include "xbeltree.h"
 
+#include <QApplication>
+#include <QFileDialog>
+#include <QMenuBar>
+#include <QMessageBox>
+#include <QStatusBar>
+
+#include <QAction>
+#include <QScreen>
+
+using namespace Qt::StringLiterals;
+
 //! [0]
 MainWindow::MainWindow()
 {
@@ -25,16 +34,15 @@ MainWindow::MainWindow()
 //! [1]
 void MainWindow::open()
 {
-    QString fileName =
+    QFileDialog fileDialog(this, tr("Open Bookmark File"), QDir::currentPath());
-            QFileDialog::getOpenFileName(this, tr("Open Bookmark File"),
+    fileDialog.setMimeTypeFilters({"application/x-xbel"_L1});
-                                         QDir::currentPath(),
+    if (fileDialog.exec() != QDialog::Accepted)
-                                         tr("XBEL Files (*.xbel *.xml)"));
-    if (fileName.isEmpty())
         return;
 
+    const QString fileName = fileDialog.selectedFiles().constFirst();
     QFile file(fileName);
     if (!file.open(QFile::ReadOnly | QFile::Text)) {
-        QMessageBox::warning(this, tr("SAX Bookmarks"),
+        QMessageBox::warning(this, tr("DOM Bookmarks"),
                              tr("Cannot read file %1:\n%2.")
                              .arg(QDir::toNativeSeparators(fileName),
                                   file.errorString()));
@@ -49,16 +57,17 @@ void MainWindow::open()
 //! [2]
 void MainWindow::saveAs()
 {
-    QString fileName =
+    QFileDialog fileDialog(this, tr("Save Bookmark File"), QDir::currentPath());
-            QFileDialog::getSaveFileName(this, tr("Save Bookmark File"),
+    fileDialog.setAcceptMode(QFileDialog::AcceptSave);
-                                         QDir::currentPath(),
+    fileDialog.setDefaultSuffix("xbel"_L1);
-                                         tr("XBEL Files (*.xbel *.xml)"));
+    fileDialog.setMimeTypeFilters({"application/x-xbel"_L1});
-    if (fileName.isEmpty())
+    if (fileDialog.exec() != QDialog::Accepted)
         return;
 
+    const QString fileName = fileDialog.selectedFiles().constFirst();
     QFile file(fileName);
     if (!file.open(QFile::WriteOnly | QFile::Text)) {
-        QMessageBox::warning(this, tr("SAX Bookmarks"),
+        QMessageBox::warning(this, tr("DOM Bookmarks"),
                              tr("Cannot write file %1:\n%2.")
                              .arg(QDir::toNativeSeparators(fileName),
                                   file.errorString()));

examples/xml/dombookmarks/xbeltree.cpp

@@ -1,31 +1,41 @@
 // Copyright (C) 2016 The Qt Company Ltd.
 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
 
-#include <QtWidgets>
-
 #include "xbeltree.h"
 
+#include <QHeaderView>
+#include <QMenu>
+#include <QMessageBox>
+
+#include <QDesktopServices>
+#include <QGuiApplication>
+#if QT_CONFIG(clipboard) && QT_CONFIG(contextmenu)
+#  include <QClipboard>
+#  include <QContextMenuEvent>
+#endif
+
+#include <QUrl>
+
+using namespace Qt::StringLiterals;
+
 enum { DomElementRole = Qt::UserRole + 1 };
 
 Q_DECLARE_METATYPE(QDomElement)
 
-static inline QString titleElement() { return QStringLiteral("title"); }
+static const auto titleElement  = u"title"_s;
-static inline QString folderElement() { return QStringLiteral("folder"); }
+static const auto folderElement = u"folder"_s;
-static inline QString bookmarkElement() { return QStringLiteral("bookmark"); }
+static const auto bookmarkElement = u"bookmark"_s;
 
-static inline QString versionAttribute() { return QStringLiteral("version"); }
+static const auto versionAttribute = u"version"_s;
-static inline QString hrefAttribute() { return QStringLiteral("href"); }
+static const auto hrefAttribute = u"href"_s;
-static inline QString foldedAttribute() { return QStringLiteral("folded"); }
+static const auto foldedAttribute = u"folded"_s;
 
 //! [0]
 XbelTree::XbelTree(QWidget *parent)
     : QTreeWidget(parent)
 {
-    QStringList labels;
-    labels << tr("Title") << tr("Location");
-
     header()->setSectionResizeMode(QHeaderView::Stretch);
-    setHeaderLabels(labels);
+    setHeaderLabels({tr("Title"), tr("Location")});
 
     folderIcon.addPixmap(style()->standardPixmap(QStyle::SP_DirClosedIcon),
                          QIcon::Normal, QIcon::Off);
@@ -35,7 +45,7 @@ XbelTree::XbelTree(QWidget *parent)
 }
 //! [0]
 
-#if !defined(QT_NO_CONTEXTMENU) && !defined(QT_NO_CLIPBOARD)
+#if QT_CONFIG(clipboard) && QT_CONFIG(contextmenu)
 void XbelTree::contextMenuEvent(QContextMenuEvent *event)
 {
     const QTreeWidgetItem *item = itemAt(event->pos());
@@ -51,7 +61,7 @@ void XbelTree::contextMenuEvent(QContextMenuEvent *event)
     else if (action == openAction)
         QDesktopServices::openUrl(QUrl(url));
 }
-#endif // !QT_NO_CONTEXTMENU && !QT_NO_CLIPBOARD
+#endif // QT_CONFIG(clipboard) && QT_CONFIG(contextmenu)
 
 //! [1]
 bool XbelTree::read(QIODevice *device)
@@ -72,8 +82,8 @@ bool XbelTree::read(QIODevice *device)
         QMessageBox::information(window(), tr("DOM Bookmarks"),
                                  tr("The file is not an XBEL file."));
         return false;
-    } else if (root.hasAttribute(versionAttribute())
+    } else if (root.hasAttribute(versionAttribute)
-               && root.attribute(versionAttribute()) != QLatin1String("1.0")) {
+               && root.attribute(versionAttribute) != "1.0"_L1) {
         QMessageBox::information(window(), tr("DOM Bookmarks"),
                                  tr("The file is not an XBEL version 1.0 "
                                     "file."));
@@ -84,10 +94,10 @@ bool XbelTree::read(QIODevice *device)
 
     disconnect(this, &QTreeWidget::itemChanged, this, &XbelTree::updateDomElement);
 
-    QDomElement child = root.firstChildElement(folderElement());
+    QDomElement child = root.firstChildElement(folderElement);
     while (!child.isNull()) {
         parseFolderElement(child);
-        child = child.nextSiblingElement(folderElement());
+        child = child.nextSiblingElement(folderElement);
     }
 
     connect(this, &QTreeWidget::itemChanged, this, &XbelTree::updateDomElement);
@@ -112,16 +122,16 @@ void XbelTree::updateDomElement(const QTreeWidgetItem *item, int column)
     QDomElement element = qvariant_cast<QDomElement>(item->data(0, DomElementRole));
     if (!element.isNull()) {
         if (column == 0) {
-            QDomElement oldTitleElement = element.firstChildElement(titleElement());
+            QDomElement oldTitleElement = element.firstChildElement(titleElement);
-            QDomElement newTitleElement = domDocument.createElement(titleElement());
+            QDomElement newTitleElement = domDocument.createElement(titleElement);
 
             QDomText newTitleText = domDocument.createTextNode(item->text(0));
             newTitleElement.appendChild(newTitleText);
 
             element.replaceChild(newTitleElement, oldTitleElement);
         } else {
-            if (element.tagName() == bookmarkElement())
+            if (element.tagName() == bookmarkElement)
-                element.setAttribute(hrefAttribute(), item->text(1));
+                element.setAttribute(hrefAttribute, item->text(1));
         }
     }
 }
@@ -132,35 +142,35 @@ void XbelTree::parseFolderElement(const QDomElement &element,
 {
     QTreeWidgetItem *item = createItem(element, parentItem);
 
-    QString title = element.firstChildElement(titleElement()).text();
+    QString title = element.firstChildElement(titleElement).text();
     if (title.isEmpty())
-        title = QObject::tr("Folder");
+        title = tr("Folder");
 
     item->setFlags(item->flags() | Qt::ItemIsEditable);
     item->setIcon(0, folderIcon);
     item->setText(0, title);
 
-    bool folded = (element.attribute(foldedAttribute()) != QLatin1String("no"));
+    bool folded = (element.attribute(foldedAttribute) != "no"_L1);
     item->setExpanded(!folded);
 
     constexpr char16_t midDot = u'\xB7';
     static const QString dots = QString(30, midDot);
     QDomElement child = element.firstChildElement();
     while (!child.isNull()) {
-        if (child.tagName() == folderElement()) {
+        if (child.tagName() == folderElement) {
             parseFolderElement(child, item);
-        } else if (child.tagName() == bookmarkElement()) {
+        } else if (child.tagName() == bookmarkElement) {
             QTreeWidgetItem *childItem = createItem(child, item);
 
-            QString title = child.firstChildElement(titleElement()).text();
+            QString title = child.firstChildElement(titleElement).text();
             if (title.isEmpty())
-                title = QObject::tr("Folder");
+                title = tr("Folder");
 
             childItem->setFlags(item->flags() | Qt::ItemIsEditable);
             childItem->setIcon(0, bookmarkIcon);
             childItem->setText(0, title);
-            childItem->setText(1, child.attribute(hrefAttribute()));
+            childItem->setText(1, child.attribute(hrefAttribute));
-        } else if (child.tagName() == QLatin1String("separator")) {
+        } else if (child.tagName() == "separator"_L1) {
             QTreeWidgetItem *childItem = createItem(child, item);
             childItem->setFlags(item->flags() & ~(Qt::ItemIsSelectable | Qt::ItemIsEditable));
             childItem->setText(0, dots);

examples/xml/dombookmarks/xbeltree.h

@@ -14,13 +14,13 @@ class XbelTree : public QTreeWidget
     Q_OBJECT
 
 public:
-    XbelTree(QWidget *parent = nullptr);
+    explicit XbelTree(QWidget *parent = nullptr);
 
     bool read(QIODevice *device);
     bool write(QIODevice *device) const;
 
 protected:
-#if !defined(QT_NO_CONTEXTMENU) && !defined(QT_NO_CLIPBOARD)
+#if QT_CONFIG(clipboard) && QT_CONFIG(contextmenu)
     void contextMenuEvent(QContextMenuEvent *event) override;
 #endif