2 files changed, 31 insertions, 20 deletions

diff --git a/src/quick/items/qquickimagebase.cpp b/src/quick/items/qquickimagebase.cpp
index 22d631e917..33d69f5032 100644
--- a/src/quick/items/qquickimagebase.cpp
+++ b/src/quick/items/qquickimagebase.cpp
@@ -49,6 +49,30 @@
 
 QT_BEGIN_NAMESPACE
 
+// This function gives derived classes the chance set the devicePixelRatio
+// if they're not happy with our implementation of it.
+bool QQuickImageBasePrivate::updateDevicePixelRatio(qreal targetDevicePixelRatio)
+{
+    // QQuickImageProvider and SVG can generate a high resolution image when
+    // sourceSize is set (this function is only called if it's set).
+    // If sourceSize is not set then the provider default size will be used, as usual.
+    bool setDevicePixelRatio = false;
+    if (url.scheme() == QLatin1String("image")) {
+        setDevicePixelRatio = true;
+    } else {
+        QString stringUrl = url.path(QUrl::PrettyDecoded);
+        if (stringUrl.endsWith(QLatin1String("svg")) ||
+            stringUrl.endsWith(QLatin1String("svgz"))) {
+            setDevicePixelRatio = true;
+        }
+    }
+
+    if (setDevicePixelRatio)
+        devicePixelRatio = targetDevicePixelRatio;
+
+    return setDevicePixelRatio;
+}
+
 QQuickImageBase::QQuickImageBase(QQuickItem *parent)
 : QQuickImplicitSizeItem(*(new QQuickImageBasePrivate), parent)
 {
@@ -221,26 +245,11 @@ void QQuickImageBase::load()
 
         QUrl loadUrl = d->url;
 
-        // QQuickImageProvider and SVG can generate a high resolution image when
-        // sourceSize is set. If sourceSize is not set then the provider default size
-        // will be used, as usual.
-        bool setDevicePixelRatio = false;
-        if (d->sourcesize.isValid()) {
-            if (loadUrl.scheme() == QLatin1String("image")) {
-                setDevicePixelRatio = true;
-            } else {
-                QString stringUrl = loadUrl.path(QUrl::PrettyDecoded);
-                if (stringUrl.endsWith(QLatin1String("svg")) ||
-                    stringUrl.endsWith(QLatin1String("svgz"))) {
-                    setDevicePixelRatio = true;
-                }
-            }
-
-            if (setDevicePixelRatio)
-                d->devicePixelRatio = targetDevicePixelRatio;
-        }
+        bool updatedDevicePixelRatio = false;
+        if (d->sourcesize.isValid())
+            updatedDevicePixelRatio = d->updateDevicePixelRatio(targetDevicePixelRatio);
 
-        if (!setDevicePixelRatio) {
+        if (!updatedDevicePixelRatio) {
             // (possible) local file: loadUrl and d->devicePixelRatio will be modified if
             // an "@2x" file is found.
             resolve2xLocalFile(d->url, targetDevicePixelRatio, &loadUrl, &d->devicePixelRatio);
diff --git a/src/quick/items/qquickimagebase_p_p.h b/src/quick/items/qquickimagebase_p_p.h
index d9b609c7fe..1b771166a2 100644
--- a/src/quick/items/qquickimagebase_p_p.h
+++ b/src/quick/items/qquickimagebase_p_p.h
@@ -59,7 +59,7 @@
 QT_BEGIN_NAMESPACE
 
 class QNetworkReply;
-class QQuickImageBasePrivate : public QQuickImplicitSizeItemPrivate
+class Q_QUICK_PRIVATE_EXPORT QQuickImageBasePrivate : public QQuickImplicitSizeItemPrivate
 {
     Q_DECLARE_PUBLIC(QQuickImageBase)
 
@@ -75,6 +75,8 @@ public:
     {
     }
 
+    virtual bool updateDevicePixelRatio(qreal targetDevicePixelRatio);
+
     QQuickPixmap pix;
     QQuickImageBase::Status status;
     QUrl url;