QIconEngine: move away from virtual_hook usage

Upgrade existing functions to be virtual functions:
  - virtual QString iconName()
  - virtual bool isNull()
  - virtual QPixmap scaledPixmap(...)
  - virtual QList<QSize> availableSizes(...)

Make all of them non-const and remove the const_casts in
the implementation. Keep the default implementation
which calls virtual_hook(), for compatibility.

Note: availableSizes was already virtual, but now loses
the “const”. Port two overrides in the platform themes.

Keep virutal_hook() around for future expansion.

Task-number: QTBUG-85885
Change-Id: I76d0c9f75bfd6ca870c669047d4ef18b82c692e5
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>

1 files changed, 3 insertions, 4 deletions

diff --git a/src/gui/image/qicon.cpp b/src/gui/image/qicon.cpp
index e7e13860d8..27206b2cbc 100644
--- a/src/gui/image/qicon.cpp
+++ b/src/gui/image/qicon.cpp
@@ -876,10 +876,9 @@ QPixmap QIcon::pixmap(const QSize &size, qreal devicePixelRatio, Mode mode, Stat
     }
 
     // Try get a pixmap that is big enough to be displayed at device pixel resolution.
-    QIconEngine::ScaledPixmapArgument scalePixmapArg = { size * devicePixelRatio, mode, state, devicePixelRatio, QPixmap() };
-    d->engine->virtual_hook(QIconEngine::ScaledPixmapHook, reinterpret_cast<void*>(&scalePixmapArg));
-    scalePixmapArg.pixmap.setDevicePixelRatio(d->pixmapDevicePixelRatio(devicePixelRatio, size, scalePixmapArg.pixmap.size()));
-    return scalePixmapArg.pixmap;
+    QPixmap pixmap = d->engine->scaledPixmap(size * devicePixelRatio, mode, state, devicePixelRatio);
+    pixmap.setDevicePixelRatio(d->pixmapDevicePixelRatio(devicePixelRatio, size, pixmap.size()));
+    return pixmap;
 }
 
 /*!