fix the fix and add vertical scroll position hack

csgui/pdfViewer.py

@@ -8,7 +8,7 @@ class PDFLabel(QLabel):
     def __init__(self, parent):
         super().__init__(parent)
         self.parent = parent
-        self.setSizePolicy(QSizePolicy.Expanding, QSizePolicy.Expanding)
+        self.setSizePolicy(QSizePolicy.MinimumExpanding, QSizePolicy.Preferred)
     
     def paintEvent(self, event):
         self.adjustSize()
@@ -37,7 +37,7 @@ class PDFLabel(QLabel):
             
             scaledPix = self.pixmap().scaled(pixSize, Qt.KeepAspectRatio, Qt.SmoothTransformation)
             painter.drawPixmap(QPoint(), scaledPix)
-            # self.setMaximumSize(pixSize)
+            self.setMaximumSize(pixSize)
 
 class PDFViewer(QScrollArea):
     def __init__(self, parent):
@@ -51,6 +51,7 @@ class PDFViewer(QScrollArea):
 
         self.scrollAreaContents.setLayout(self.scrollAreaLayout)
         self.pixmapList = []      
+        self.lastVScrollPosition = None
     
     def update_pdf(self, pdf):
         self.render(pdf)
@@ -69,6 +70,7 @@ class PDFViewer(QScrollArea):
             self.pixmapList.append(page.get_pixmap(dpi=300, alpha=False))
                     
     def clear(self):
+        self.lastVScrollPosition = self.verticalScrollBar().value()
         while self.scrollAreaLayout.count():
             item = self.scrollAreaLayout.takeAt(0)
             w = item.widget()
@@ -83,4 +85,9 @@ class PDFViewer(QScrollArea):
             label.setPixmap(QPixmap.fromImage(qtimg))
             self.scrollAreaLayout.addWidget(label)
         
-        # self.scrollAreaLayout.addStretch(1)
+        self.scrollAreaLayout.addStretch(1)
+        
+        # Somewhat of a hack. Should really replace pixmaps in place
+        # rather than removing labels elsewhere in code.
+        if self.lastVScrollPosition:
+            self.verticalScrollBar().setValue(self.lastVScrollPosition)