gdaltools batch operations: only update progress when there are input…

… files to process

python/plugins/GdalTools/tools/widgetBatchBase.py

@@ -74,17 +74,18 @@ def onRun( self ):
       self.batchRun()
 
   def batchRun(self):
-      self.base.enableRun( False )
-      self.base.setCursor( Qt.WaitCursor )
-
-      inDir = self.getInputFileName()
+      self.inFiles = Utils.getRasterFiles( self.getInputFileName(), self.isRecursiveScanEnabled() )
+      if len(self.inFiles) == 0: 
+        QMessageBox.warning( self, self.tr( "Warning" ), self.tr( "No input files to process." ) )
+        return
 
-      self.inFiles = Utils.getRasterFiles( inDir, self.isRecursiveScanEnabled() )
       self.outFiles = []
-
       for f in self.inFiles:
         self.outFiles.append( self.getBatchOutputFileName( f ) )
 
+      self.base.enableRun( False )
+      self.base.setCursor( Qt.WaitCursor )
+
       self.errors = []
       self.batchIndex = 0
       self.batchTotal = len( self.inFiles )