[Qgis-developer] Not Rendering the Shapefile in Canvas - Blank

[Noli Sicad]

Hi,

Is there any reason why the shapefile is not rendering in this code
(below)? I tried several shapefiles and yet I am getting a white
canvas or blank canvas without a render. I was able to open the
shapefile and the form with mapcanvas are showing. Yet no render of
the polygons - totally blank.

self.canvas.setCanvasColor(Qt.white)  <---- a White Canvas without
render - BLANK

Thanks. Noli


~~~~~~~~~~~~~~~~
class ShapeViewer(QMainWindow, Ui_MainWindow):

  def __init__(self):
    QMainWindow.__init__(self)

    # Required by Qt4 to initialize the UI
    self.setupUi(self)

    # Set the title for the app
    self.setWindowTitle("ShapeViewer")

    # Create the map canvas
    self.canvas = QgsMapCanvas()
    self.canvas.useImageToRender(False)
    self.canvas.show()

    # Lay our widgets out in the main window using a
    # vertical box layout
    self.layout = QVBoxLayout(self.frame)
    self.layout.addWidget(self.canvas)

    # layout is set - open a layer
    # Add an OGR layer to the map
    file = QFileDialog.getOpenFileName(self,
                   "Open Shapefile", ".", "Shapefiles (*.shp)")
    fileInfo = QFileInfo(file)

    # Add the layer
    layer = QgsVectorLayer(file, fileInfo.fileName(), "ogr")

    if not layer.isValid():
      return

     # Add layer to the registry
    QgsMapLayerRegistry.instance().addMapLayer(layer);

    # Set extent to the extent of our layer
    self.canvas.setExtent(layer.extent())

    # Set up the map canvas layer set
    cl = QgsMapCanvasLayer(layer)
    layers = [cl]
    self.canvas.setLayerSet(layers)