Fix warnings about scaling pixmaps

src/kitemviews/kfileitemlistview.cpp

@@ -168,7 +168,12 @@ QPixmap KFileItemListView::createDragPixmap(const KItemSet& indexes) const
         QPixmap pixmap = model()->data(index).value("iconPixmap").value<QPixmap>();
         if (pixmap.isNull()) {
             QIcon icon = QIcon::fromTheme(model()->data(index).value("iconName").toString());
-            pixmap = icon.pixmap(size, size);
+            if (!icon.isNull()) {
+                pixmap = icon.pixmap(size, size);
+            } else {
+                pixmap = QPixmap(size, size);
+                pixmap.fill(Qt::transparent);
+            }
         } else {
             KPixmapModifier::scale(pixmap, QSize(size, size) * dpr);
         }

src/kitemviews/kfileitemmodelrolesupdater.cpp

@@ -494,7 +494,7 @@ void KFileItemModelRolesUpdater::slotGotPreview(const KFileItem& item, const QPi
 
     QPixmap scaledPixmap = pixmap;
 
-    if (!pixmap.hasAlpha()
+    if (!pixmap.hasAlpha() && !pixmap.isNull()
         && m_iconSize.width()  > KIconLoader::SizeSmallMedium
         && m_iconSize.height() > KIconLoader::SizeSmallMedium) {
         if (m_enlargeSmallPreviews) {
@@ -525,7 +525,7 @@ void KFileItemModelRolesUpdater::slotGotPreview(const KFileItem& item, const QPi
                 KPixmapModifier::applyFrame(scaledPixmap, m_iconSize);
             }
         }
-    } else {
+    } else if (!pixmap.isNull()) {
         KPixmapModifier::scale(scaledPixmap, m_iconSize * qApp->devicePixelRatio());
         scaledPixmap.setDevicePixelRatio(qApp->devicePixelRatio());
     }
@@ -538,12 +538,14 @@ void KFileItemModelRolesUpdater::slotGotPreview(const KFileItem& item, const QPi
     // It is more efficient to do it here, as KIconLoader::drawOverlays()
     // assumes that an overlay will be drawn and has some additional
     // setup time.
-    for (const QString& overlay : overlays) {
-        if (!overlay.isEmpty()) {
-            // There is at least one overlay, draw all overlays above m_pixmap
-            // and cancel the check
-            KIconLoader::global()->drawOverlays(overlays, scaledPixmap, KIconLoader::Desktop);
-            break;
+    if (!scaledPixmap.isNull()) {
+        for (const QString& overlay : overlays) {
+            if (!overlay.isEmpty()) {
+                // There is at least one overlay, draw all overlays above m_pixmap
+                // and cancel the check
+                KIconLoader::global()->drawOverlays(overlays, scaledPixmap, KIconLoader::Desktop);
+                break;
+            }
         }
     }
 

src/kitemviews/kstandarditemlistwidget.cpp

@@ -314,7 +314,7 @@ void KStandardItemListWidget::paint(QPainter* painter, const QStyleOptionGraphic
     }
 
     const KItemListStyleOption& itemListStyleOption = styleOption();
-    if (isHovered()) {
+    if (isHovered() && !m_pixmap.isNull()) {
         if (hoverOpacity() < 1.0) {
             /*
              * Linear interpolation between m_pixmap and m_hoverPixmap.
@@ -357,7 +357,7 @@ void KStandardItemListWidget::paint(QPainter* painter, const QStyleOptionGraphic
         } else {
             drawPixmap(painter, m_hoverPixmap);
         }
-    } else {
+    } else if (!m_pixmap.isNull()) {
         drawPixmap(painter, m_pixmap);
     }
 
@@ -962,6 +962,11 @@ void KStandardItemListWidget::updatePixmapCache()
             KPixmapModifier::scale(m_pixmap, QSize(maxIconWidth, maxIconHeight) * qApp->devicePixelRatio());
         }
 
+        if (m_pixmap.isNull()) {
+            m_hoverPixmap = QPixmap();
+            return;
+        }
+
         if (m_isCut) {
             KIconEffect* effect = KIconLoader::global()->iconEffect();
             m_pixmap = effect->apply(m_pixmap, KIconLoader::Desktop, KIconLoader::DisabledState);
@@ -974,6 +979,10 @@ void KStandardItemListWidget::updatePixmapCache()
         if (m_layout == IconsLayout && isSelected()) {
             const QColor color = palette().brush(QPalette::Normal, QPalette::Highlight).color();
             QImage image = m_pixmap.toImage();
+            if (image.isNull()) {
+                m_hoverPixmap = QPixmap();
+                return;
+            }
             KIconEffect::colorize(image, color, 0.8f);
             m_pixmap = QPixmap::fromImage(image);
         }

src/kitemviews/private/kpixmapmodifier.cpp

@@ -298,7 +298,7 @@ namespace {
 
 void KPixmapModifier::scale(QPixmap& pixmap, const QSize& scaledSize)
 {
-    if (scaledSize.isEmpty()) {
+    if (scaledSize.isEmpty() || pixmap.isNull()) {
         pixmap = QPixmap();
         return;
     }
@@ -309,6 +309,12 @@ void KPixmapModifier::scale(QPixmap& pixmap, const QSize& scaledSize)
 
 void KPixmapModifier::applyFrame(QPixmap& icon, const QSize& scaledSize)
 {
+    if (icon.isNull()) {
+        icon = QPixmap(scaledSize);
+        icon.fill(Qt::transparent);
+        return;
+    }
+
     static TileSet tileSet;
     qreal dpr = qApp->devicePixelRatio();
 

src/panels/information/pixmapviewer.cpp

@@ -136,7 +136,7 @@ void PixmapViewer::paintEvent(QPaintEvent* event)
 
             style()->drawItemPixmap(&painter, rect(), Qt::AlignCenter, scaledPixmap);
         }
-    } else {
+    } else if (!m_pixmap.isNull()) {
         style()->drawItemPixmap(&painter, rect(), Qt::AlignCenter, m_pixmap);
     }
 }