Q{File,Font,Color,Message}DialogOptions are no value classes

These classes are only held in QSharedPointer, so optimize for that:

1. Disable default ctor, copy ctor and assignment operator,
   destructor and swap for public users.
2. Add create() to return an instance in a shared pointer.
3. Allocate public and private classes in one memory block,
   use QSharedPointer::create() to also add the QSharedPointer
   control block to the same memory allocation.

As a consequence, this reduces the creation of a Q*DialogOptions
into a shared pointer by two memory allocations.

Add a macro to enable atomic updates to QtQuick and other users
outside QtBase.

[ChangeLog][QtGui]
[QFileDialogOptions/QFontDialogOptions/QMessageDialogOptions/QColorDialogOptions]
This class no longer has value semantics, but needs to be held
in QSharedPointer (as it always was). To copy an instance, use
the clone() method.

Change-Id: I4c81220e0a8286a310df1c224a30eca34824c4e6
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@theqtcompany.com>
Reviewed-by: Lars Knoll <lars.knoll@theqtcompany.com>
Reviewed-by: Shawn Rutledge <shawn.rutledge@theqtcompany.com>

4 files changed, 4 insertions, 4 deletions

diff --git a/src/widgets/dialogs/qcolordialog.cpp b/src/widgets/dialogs/qcolordialog.cpp
index 9f86bea0ca..beeef75fb5 100644
--- a/src/widgets/dialogs/qcolordialog.cpp
+++ b/src/widgets/dialogs/qcolordialog.cpp
@@ -92,7 +92,7 @@ public:
         SetColorAll = ShowColor | SelectColor
     };
 
-    QColorDialogPrivate() : options(new QColorDialogOptions)
+    QColorDialogPrivate() : options(QColorDialogOptions::create())
 #ifdef Q_OS_WIN32
         , updateTimer(0)
 #endif
diff --git a/src/widgets/dialogs/qfiledialog.cpp b/src/widgets/dialogs/qfiledialog.cpp
index 50667e2a91..3bcd6f7c4b 100644
--- a/src/widgets/dialogs/qfiledialog.cpp
+++ b/src/widgets/dialogs/qfiledialog.cpp
@@ -533,7 +533,7 @@ QFileDialogPrivate::QFileDialogPrivate()
         showHiddenAction(0),
         useDefaultCaption(true),
         qFileDialogUi(0),
-        options(new QFileDialogOptions)
+        options(QFileDialogOptions::create())
 {
 }
 
diff --git a/src/widgets/dialogs/qfontdialog.cpp b/src/widgets/dialogs/qfontdialog.cpp
index a0525f6fbd..c130998198 100644
--- a/src/widgets/dialogs/qfontdialog.cpp
+++ b/src/widgets/dialogs/qfontdialog.cpp
@@ -110,7 +110,7 @@ static const Qt::WindowFlags DefaultWindowFlags =
 
 QFontDialogPrivate::QFontDialogPrivate()
     : writingSystem(QFontDatabase::Any),
-      options(QSharedPointer<QFontDialogOptions>::create())
+      options(QFontDialogOptions::create())
 {
 }
 
diff --git a/src/widgets/dialogs/qmessagebox.cpp b/src/widgets/dialogs/qmessagebox.cpp
index 207b6e3919..ee760c38a0 100644
--- a/src/widgets/dialogs/qmessagebox.cpp
+++ b/src/widgets/dialogs/qmessagebox.cpp
@@ -200,7 +200,7 @@ public:
 #endif
                            compatMode(false), autoAddOkButton(true),
                            detectedEscapeButton(0), informativeLabel(0),
-                           options(new QMessageDialogOptions) { }
+                           options(QMessageDialogOptions::create()) { }
 
     void init(const QString &title = QString(), const QString &text = QString());
     void setupLayout();