Performance improvement in FileView

This was a tricky one. Once again SheMov spinned at almost 100% CPU
usage. This time FileView::event() was the culprit. Because FileView
uses a QFileSystemModel it receives QTimer-Events every second.

Unfortunately a static_cast from QEvent::Timer to QEvent::Hover*
succeeds so we fetched the cursor position every second and tried to get
a QModelIndex. This obviously is quite expensive.

Fixed it by checking if e->type() is of QEvent::Hover* right at the
beginning of FileView::event().

1 files changed, 43 insertions, 45 deletions

diff --git a/fileview.cpp b/fileview.cpp
index cbdd8e0..f4f5294 100644
--- a/fileview.cpp
+++ b/fileview.cpp
@@ -149,61 +149,59 @@ void FileView::resizeEvent(QResizeEvent *e){
 }
 
 bool FileView::event(QEvent *e){
-	QHoverEvent *hEvent = static_cast<QHoverEvent*>(e);
-	if(!hEvent){
-		return QTreeView::event(e);
-	}
-	if(!mHover){
-		return true;
-	}
-	if(e->type() == QEvent::HoverLeave){
-		return exitHover();
-	}
-	QPoint hotSpot(hEvent->pos().x(), hEvent->pos().y() - SmGlobals::instance()->cursorSize().height());
-	QModelIndex curIdx = indexAt(hotSpot);
-	if((e->type() == QEvent::HoverEnter) || (e->type() == QEvent::HoverMove)){
+	int eType = e->type();
+	if((eType == QEvent::HoverEnter) || (eType == QEvent::HoverLeave) || (eType == QEvent::HoverMove)){
+		QHoverEvent *hEvent = static_cast<QHoverEvent*>(e);
+		if(!mHover){
+			return true;
+		}
+		if(hEvent->type() == QEvent::HoverLeave){
+			return exitHover();
+		}
+		QPoint hotSpot(hEvent->pos().x(), hEvent->pos().y() - SmGlobals::instance()->cursorSize().height());
+		QModelIndex curIdx = indexAt(hotSpot);
 		if(!curIdx.isValid() || (curIdx.column() != 0)){
 			return exitHover();
 		}
-	}
-	QFileInfo fi(curIdx.data(QFileSystemModel::FilePathRole).toString());
-	if(!fi.exists()){
-		return true;
-	}
-	QList<QVariant> hoverData;
-	if(fi.isDir()){
-		hoverData << fi.fileName();
-		QDir curDir(fi.absoluteFilePath());
-		QStringList files = curDir.entryList(QDir::AllEntries | QDir::NoDotAndDotDot, QDir::Name);
-		hoverData << files;
-	}else if(fi.isFile()){
-		QString mimeType = Helper::mimeType(fi.absoluteFilePath());
-		if(mimeType.startsWith("image")){
-			QPixmap pm(fi.absoluteFilePath());
-			hoverData << pm;
+		QFileInfo fi(curIdx.data(QFileSystemModel::FilePathRole).toString());
+		if(!fi.exists()){
+			return true;
+		}
+		QList<QVariant> hoverData;
+		if(fi.isDir()){
+			hoverData << fi.fileName();
+			QDir curDir(fi.absoluteFilePath());
+			QStringList files = curDir.entryList(QDir::AllEntries | QDir::NoDotAndDotDot, QDir::Name);
+			hoverData << files;
+		}else if(fi.isFile()){
+			QString mimeType = Helper::mimeType(fi.absoluteFilePath());
+			if(mimeType.startsWith("image")){
+				QPixmap pm(fi.absoluteFilePath());
+				hoverData << pm;
+			}else{
+				return exitHover();
+			}
 		}else{
 			return exitHover();
 		}
-	}else{
-		return exitHover();
-	}
-	if(e->type() == QEvent::HoverEnter){
-		mCurHover = curIdx;
-		mHoverWin->setData(hoverData);
-		mHoverWin->setPos();
-		mHoverWin->setVisible(true);
-		return true;
-	}
-	if(e->type() == QEvent::HoverMove){
-		if(curIdx != mCurHover){
-			mHoverWin->setData(hoverData);
+		if(e->type() == QEvent::HoverEnter){
 			mCurHover = curIdx;
+			mHoverWin->setData(hoverData);
 			mHoverWin->setPos();
 			mHoverWin->setVisible(true);
 			return true;
-		}else{
-			mHoverWin->setPos();
-			return true;
+		}
+		if(e->type() == QEvent::HoverMove){
+			if(curIdx != mCurHover){
+				mHoverWin->setData(hoverData);
+				mCurHover = curIdx;
+				mHoverWin->setPos();
+				mHoverWin->setVisible(true);
+				return true;
+			}else{
+				mHoverWin->setPos();
+				return true;
+			}
 		}
 	}
 	return QTreeView::event(e);