wxGUIwxpsmap: minor changes in generating temp file

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@50526 15284696-431f-4ddb-bdfa-cd5b030d7da7

gui/wxpython/psmap/frame.py

@@ -145,7 +145,7 @@ class PsMapFrame(wx.Frame):
         
         # image path
         env = grass.gisenv()
-        self.imgName = os.path.join(env['GISDBASE'], env['LOCATION_NAME'], env['MAPSET'], '.tmp', 'tmpImage.png')
+        self.imgName = grass.tempfile()
         
         #canvas for preview
         self.previewCanvas = PsMapBufferedWindow(parent = self, mouse = self.mouse, cursors = self.cursors,
@@ -316,12 +316,12 @@ class PsMapFrame(wx.Frame):
                 if self.instruction[self.pageId]['Orientation'] == 'Landscape':
                     im = im.rotate(270)
                 
-                im.save(self.imgName, format = 'png')
+                im.save(self.imgName, format = 'PNG')
                 
             except IOError, e:
                 GError(parent = self,
                        message = _("Unable to generate preview. %s") % e)
-            
+                return
             
                 
             rect = self.previewCanvas.ImageRect()