new function bool hasElementPrefix(prefix) that checks if the given

element prefix exists for the loaded svg
and build fix woops

svn path=/trunk/KDE/kdebase/workspace/libs/plasma/; revision=803066

panelsvg.cpp

@@ -153,6 +153,13 @@ void PanelSvg::setElementPrefix(Plasma::Location location)
     d->location = location;
 }
 
+bool PanelSvg::hasElementPrefix(const QString & prefix) const
+{
+    //for now it simply checks if a center element exists,
+    //because it could make sense for certain themes to not have all the elements
+    return hasElement(prefix + "-center");
+}
+
 void PanelSvg::setElementPrefix(const QString & prefix)
 {
     const QString oldPrefix(d->prefix);
@@ -364,8 +371,7 @@ void PanelSvg::Private::generateBackground(PanelData *panel)
             }
 
             p.drawTiledPixmap(QRect(panel->leftWidth, panel->topHeight,
-                                    contentWidth, contentHeight),
-                                    prefix + "center"), center);
+                                    contentWidth, contentHeight), center);
         }
     } else {
         if (contentHeight > 0 && contentWidth > 0) {

panelsvg.h

@@ -133,6 +133,13 @@ class PLASMA_EXPORT PanelSvg : public Svg
          */
         void setElementPrefix(const QString & prefix);
 
+        /**
+         * @return true if the svg has the necessary elements with the given prefix
+         * to draw a panel
+         * @arg prefix the given prefix we want to check if drawable
+         */
+        bool hasElementPrefix(const QString & prefix) const;
+
         /**
          * Returns the prefix for SVG elements of the PanelSvg
          * @return the prefix