Interactively setting the current workspace using the ToolValidator class

JimOakleaf

I have a tool which has the user select a workspace in the first parameter.  Once the user selects the appropriate workspace I would then like the tool's environmental settings to be changed so the current workspace be set to that select workspace.  What I am hoping to accomplish is if the user just inputs a name in a feature class output parameter, the new featureclass will be created in the previously selected workspace by default.  I have tried using the ToolValidator however it doesn't seem to change the tool's environment settings.  I have included code from my ToolValidator class showing two ways I have tried to accomplish this.

Thanks for any advice or suggestions,
Jim Oakleaf



class ToolValidator:
  def __init__(self):
    import arcpy
    self.params = arcpy.GetParameterInfo() 

  def initializeParameters(self):
    return

  def updateParameters(self):
    if self.params[0].altered:
      theW = self.params[0].value
      dsW=arcpy.Describe(theW)
      arcpy.env.workspace=dsW.catalogPath  """Tried this method"""
      arcpy.env.scratchWorkspace=theW   """Also tried this method"""

  def updateMessages(self):
    return

curtvprice

Unfortunately before moving away from the input box ArcGIS is placing a workspace in front of the inputted name.  I am just going to go with a warning for users and move on.  Your code helped me figure out how to do this, so thanks!

    if self.params[0].value and self.params[6].altered:
      outFC = str(self.params[6].value)
      self.params[6].clearMessage
      import os
      if os.path.dirname(outFC)!= str(self.params[0].value):
        self.params[6].setWarningMessage("Output location not within project folder!")

You're right, the internal validation for output filenames gets there before we can alter it (when the output parameter is initialized).

For best results, be sure and update parameter values in the updateParameters function -- and set validation messages (like setWarningMessage above) in the updateMessages function.

Here's the way I'd do it:

  def updateMessages(self):
    """Modify the messages created by internal validation for each tool
    parameter.  This method is called after internal validation."""
    if self.params[0].value and self.params[6].value:
      import os
      inWS = os.path.dirname(str(self.params[0].value))
      outWS = os.path.dirname(str(self.params[6].value))
      if inWS != outWS:
        self.params[6].setWarningMessage(
          "Output will be written to a different workspace than input!")
    return