Load "@2x" images on high-dpi "retina" systems.

Check for the existence of a "@2x" file when adding
an image to QIcon. For example, adding "foo.png" will
also add "foo@2x.png" if that file exists.

Change-Id: If32a3446cf56ca0828de17f6a361091e4c874f26
Reviewed-by: Gabriel de Dietrich <gabriel.dedietrich@digia.com>

1 files changed, 11 insertions, 0 deletions

diff --git a/src/gui/image/qicon.cpp b/src/gui/image/qicon.cpp
index 683fe51d2b..d73cd0aa57 100644
--- a/src/gui/image/qicon.cpp
+++ b/src/gui/image/qicon.cpp
@@ -958,6 +958,17 @@ void QIcon::addFile(const QString &fileName, const QSize &size, Mode mode, State
         detach();
     }
     d->engine->addFile(fileName, size, mode, state);
+
+    // Check if a "@2x" file exists and add it.
+    if (qApp->devicePixelRatio() > 1.0) {
+        int dotIndex = fileName.lastIndexOf(QLatin1Char('.'));
+        if (dotIndex != -1) {
+            QString at2xfileName = fileName;
+            at2xfileName.insert(dotIndex, QStringLiteral("@2x"));
+            if (QFile::exists(at2xfileName))
+                d->engine->addFile(at2xfileName, size, mode, state);
+        }
+    }
 }
 
 /*!