QtPlatformSupport: Add QAbstractFileIconEngine

Move the code from QtWidgets/QFileIconEngine into a new class with
virtuals in QtPlatformSupport so that platforms can reuse it.

Prototypically use the class in the Windows and macOS QPA plugins.

Remove QPlatformTheme::fileIconPixmap() and change the type
of the hint QPlatformTheme::IconPixmapSizes from QList<int>
to QList<QSize> so that it fits better with the icon code.

Change-Id: I580e936f3507218757565ca099272cd575b3a779
Reviewed-by: Olivier Goffart (Woboq GmbH) <ogoffart@woboq.com>

1 files changed, 7 insertions, 4 deletions

diff --git a/src/plugins/platforms/windows/qwindowstheme.h b/src/plugins/platforms/windows/qwindowstheme.h
index fa1fb4d998..0384899efa 100644
--- a/src/plugins/platforms/windows/qwindowstheme.h
+++ b/src/plugins/platforms/windows/qwindowstheme.h
@@ -43,6 +43,7 @@
 #include "qwindowsthreadpoolrunner.h"
 #include <qpa/qplatformtheme.h>
 
+#include <QtCore/QSharedPointer>
 #include <QtCore/QVariant>
 
 QT_BEGIN_NAMESPACE
@@ -66,12 +67,14 @@ public:
         { return m_fonts[type]; }
 
     QPixmap standardPixmap(StandardPixmap sp, const QSizeF &size) const Q_DECL_OVERRIDE;
-    QPixmap fileIconPixmap(const QFileInfo &fileInfo, const QSizeF &size,
-                           QPlatformTheme::IconOptions iconOptions = 0) const Q_DECL_OVERRIDE;
+
+    QIcon fileIcon(const QFileInfo &fileInfo, QPlatformTheme::IconOptions iconOptions = 0) const override;
 
     void windowsThemeChanged(QWindow *window);
     void displayChanged() { refreshIconPixmapSizes(); }
 
+    QList<QSize> availableFileIconSizes() const { return m_fileIconSizes; }
+
     static const char *name;
 
 private:
@@ -85,8 +88,8 @@ private:
     static QWindowsTheme *m_instance;
     QPalette *m_palettes[NPalettes];
     QFont *m_fonts[NFonts];
-    mutable QWindowsThreadPoolRunner m_threadPoolRunner;
-    QVariant m_fileIconSizes;
+    const QSharedPointer<QWindowsThreadPoolRunner> m_threadPoolRunner;
+    QList<QSize> m_fileIconSizes;
 };
 
 QT_END_NAMESPACE