clean ups

openlp/core/ui/maindisplay.py

@@ -137,11 +137,10 @@ class MainDisplay(DisplayWidget):
             painter_image.begin(initialFrame)
             painter_image.fillRect(initialFrame.rect(), QtCore.Qt.white)
             painter_image.drawImage(
-                (self.screens.current[u'size'].width() \
-                    - splash_image.width()) / 2,
-                (self.screens.current[u'size'].height() \
-                    - splash_image.height()) / 2,
-                splash_image)
+                (self.screens.current[u'size'].width() - 
+                splash_image.width()) / 2,
+                (self.screens.current[u'size'].height()
+                - splash_image.height()) / 2, splash_image)
             serviceItem = ServiceItem()
             serviceItem.bg_image_bytes = image_to_byte(initialFrame)
             self.webView.setHtml(build_html(serviceItem, self.screen,

openlp/core/ui/slidecontroller.py

@@ -899,7 +899,11 @@ class SlideController(QtGui.QWidget):
             row)
 
     def updatePreview(self):
-        log.debug(u'updatePreview %s ' %self.screens.current[u'primary'])
+        """
+        This updates the preview frame, for example after changing a slide or
+        using *Blank to Theme*.
+        """
+        log.debug(u'updatePreview %s ' % self.screens.current[u'primary'])
         if not self.screens.current[u'primary']:
             # Grab now, but try again in a couple of seconds if slide change
             # is slow
@@ -910,6 +914,9 @@ class SlideController(QtGui.QWidget):
                 QtGui.QPixmap.fromImage(self.display.preview()))
 
     def grabMainDisplay(self):
+        """
+        Creates an image of the current screen and updates the preview frame.
+        """
         winid = QtGui.QApplication.desktop().winId()
         rect = self.screens.current[u'size']
         winimg = QtGui.QPixmap.grabWindow(winid, rect.x(),