Use icon themes in QPrintPreviewDialog [if they exist]

I've renamed a few of the qrc icons to the names most common icon themes use
for similar actions (the action themselves are not part of the icon naming spec
https://specifications.freedesktop.org/icon-naming-spec/icon-naming-spec-latest.html
since it's not been updated in a while).

Task-number: QTBUG-85879
Change-Id: I23bb300dbf4e953517516c97b8af118859aeb6fa
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>

src/printsupport/CMakeLists.txt

@@ -103,10 +103,10 @@ qt_internal_extend_target(PrintSupport CONDITION QT_FEATURE_printdialog
 if(QT_FEATURE_printdialog)
     # Resources:
     set(qprintdialog_resource_files
-        "dialogs/images/fit-page-24.png"
-        "dialogs/images/fit-page-32.png"
-        "dialogs/images/fit-width-24.png"
-        "dialogs/images/fit-width-32.png"
+        "dialogs/images/zoom-fit-page-24.png"
+        "dialogs/images/zoom-fit-page-32.png"
+        "dialogs/images/zoom-fit-width-24.png"
+        "dialogs/images/zoom-fit-width-32.png"
         "dialogs/images/go-first-24.png"
         "dialogs/images/go-first-32.png"
         "dialogs/images/go-last-24.png"
@@ -121,14 +121,14 @@ if(QT_FEATURE_printdialog)
         "dialogs/images/layout-portrait-32.png"
         "dialogs/images/page-setup-24.png"
         "dialogs/images/page-setup-32.png"
-        "dialogs/images/print-24.png"
-        "dialogs/images/print-32.png"
-        "dialogs/images/view-page-multi-24.png"
-        "dialogs/images/view-page-multi-32.png"
-        "dialogs/images/view-page-one-24.png"
-        "dialogs/images/view-page-one-32.png"
-        "dialogs/images/view-page-sided-24.png"
-        "dialogs/images/view-page-sided-32.png"
+        "dialogs/images/printer-24.png"
+        "dialogs/images/printer-32.png"
+        "dialogs/images/view-pages-overview-24.png"
+        "dialogs/images/view-pages-overview-32.png"
+        "dialogs/images/view-pages-single-24.png"
+        "dialogs/images/view-pages-single-32.png"
+        "dialogs/images/view-pages-facing-24.png"
+        "dialogs/images/view-pages-facing-32.png"
         "dialogs/images/zoom-in-24.png"
         "dialogs/images/zoom-in-32.png"
         "dialogs/images/zoom-out-24.png"

src/printsupport/dialogs/qprintdialog.qrc

@@ -1,9 +1,9 @@
 <!DOCTYPE RCC><RCC version="1.0">
 <qresource prefix="/qt-project.org/dialogs/qprintpreviewdialog">
-<file>images/fit-page-24.png</file>
-<file>images/fit-page-32.png</file>
-<file>images/fit-width-24.png</file>
-<file>images/fit-width-32.png</file>
+<file>images/zoom-fit-page-24.png</file>
+<file>images/zoom-fit-page-32.png</file>
+<file>images/zoom-fit-width-24.png</file>
+<file>images/zoom-fit-width-32.png</file>
 <file>images/go-first-24.png</file>
 <file>images/go-first-32.png</file>
 <file>images/go-last-24.png</file>
@@ -18,14 +18,14 @@
 <file>images/layout-portrait-32.png</file>
 <file>images/page-setup-24.png</file>
 <file>images/page-setup-32.png</file>
-<file>images/print-24.png</file>
-<file>images/print-32.png</file>
-<file>images/view-page-multi-24.png</file>
-<file>images/view-page-multi-32.png</file>
-<file>images/view-page-one-24.png</file>
-<file>images/view-page-one-32.png</file>
-<file>images/view-page-sided-24.png</file>
-<file>images/view-page-sided-32.png</file>
+<file>images/printer-24.png</file>
+<file>images/printer-32.png</file>
+<file>images/view-pages-overview-24.png</file>
+<file>images/view-pages-overview-32.png</file>
+<file>images/view-pages-single-24.png</file>
+<file>images/view-pages-single-32.png</file>
+<file>images/view-pages-facing-24.png</file>
+<file>images/view-pages-facing-32.png</file>
 <file>images/zoom-in-24.png</file>
 <file>images/zoom-in-32.png</file>
 <file>images/zoom-out-24.png</file>

src/printsupport/dialogs/qprintpreviewdialog.cpp

@@ -353,7 +353,7 @@ void QPrintPreviewDialogPrivate::init(QPrinter *_printer)
 static inline void qt_setupActionIcon(QAction *action, QLatin1String name)
 {
     QLatin1String imagePrefix(":/qt-project.org/dialogs/qprintpreviewdialog/images/");
-    QIcon icon;
+    QIcon icon = QIcon::fromTheme(name);
     icon.addFile(imagePrefix + name + QLatin1String("-24.png"), QSize(24, 24));
     icon.addFile(imagePrefix + name + QLatin1String("-32.png"), QSize(32, 32));
     action->setIcon(icon);
@@ -384,8 +384,8 @@ void QPrintPreviewDialogPrivate::setupActions()
     fitPageAction->setObjectName(QLatin1String("fitPageAction"));
     fitWidthAction->setCheckable(true);
     fitPageAction->setCheckable(true);
-    qt_setupActionIcon(fitWidthAction, QLatin1String("fit-width"));
-    qt_setupActionIcon(fitPageAction, QLatin1String("fit-page"));
+    qt_setupActionIcon(fitWidthAction, QLatin1String("zoom-fit-width"));
+    qt_setupActionIcon(fitPageAction, QLatin1String("zoom-fit-page"));
     QObject::connect(fitGroup, SIGNAL(triggered(QAction*)), q, SLOT(_q_fit(QAction*)));
 
     // Zoom
@@ -411,9 +411,9 @@ void QPrintPreviewDialogPrivate::setupActions()
     singleModeAction = modeGroup->addAction(QCoreApplication::translate("QPrintPreviewDialog", "Show single page"));
     facingModeAction = modeGroup->addAction(QCoreApplication::translate("QPrintPreviewDialog", "Show facing pages"));
     overviewModeAction = modeGroup->addAction(QCoreApplication::translate("QPrintPreviewDialog", "Show overview of all pages"));
-    qt_setupActionIcon(singleModeAction, QLatin1String("view-page-one"));
-    qt_setupActionIcon(facingModeAction, QLatin1String("view-page-sided"));
-    qt_setupActionIcon(overviewModeAction, QLatin1String("view-page-multi"));
+    qt_setupActionIcon(singleModeAction, QLatin1String("view-pages-single"));
+    qt_setupActionIcon(facingModeAction, QLatin1String("view-pages-facing"));
+    qt_setupActionIcon(overviewModeAction, QLatin1String("view-pages-overview"));
     singleModeAction->setObjectName(QLatin1String("singleModeAction"));
     facingModeAction->setObjectName(QLatin1String("facingModeAction"));
     overviewModeAction->setObjectName(QLatin1String("overviewModeAction"));
@@ -427,7 +427,7 @@ void QPrintPreviewDialogPrivate::setupActions()
     printerGroup = new QActionGroup(q);
     printAction = printerGroup->addAction(QCoreApplication::translate("QPrintPreviewDialog", "Print"));
     pageSetupAction = printerGroup->addAction(QCoreApplication::translate("QPrintPreviewDialog", "Page setup"));
-    qt_setupActionIcon(printAction, QLatin1String("print"));
+    qt_setupActionIcon(printAction, QLatin1String("printer"));
     qt_setupActionIcon(pageSetupAction, QLatin1String("page-setup"));
     QObject::connect(printAction, SIGNAL(triggered(bool)), q, SLOT(_q_print()));
     QObject::connect(pageSetupAction, SIGNAL(triggered(bool)), q, SLOT(_q_pageSetup()));