Add points to shapefile and display over map interactively using Python Add-Ins

Question

I want to add points to a shapefile interactively using pythonaddins and display them over map. Points are added to shapefile but not to display. Please suggest how to fix this discrepancy.

class AddPoints(object):
   """Implementation for points_addin.tool1 (Tool)"""
   def __init__(self):
       self.enabled = False
       self.shape = 3

   def onMouseDownMap(self, x, y, button, shift):
       xy = (x,y)
       cursor = arcpy.da.InsertCursor(r'C:/temp/points.shp', ("SHAPE@XY"))
       cursor.insertRow([xy])

       arcpy.RefreshTOC()
       arcpy.RefreshActiveView()

Wait, it worked. I restarted my machine and now it is displaying points :) — Ibe
– Ibe, Commented Jun 20, 2014 at 4:29
Were there any points in there to start with? Odd things can happen with new feature class when you first add feature, it has to do with the extent starting from nothing and becoming something, sometimes the feature is not picked up. — Michael Stimson
– Michael Stimson, Commented Jun 20, 2014 at 4:36
A new shapefile is created every time before running above tool. Points are then added. It was somehow storing the points whenever I clicked on map but was not displaying it. — Ibe
– Ibe, Commented Jun 20, 2014 at 4:39
I think you might need to delete the cursor to flush it. This releases locks also. Perhaps a with statement would solve it, otherwise del cursor before arcpy.RefreshTOC(). — Michael Stimson
– Michael Stimson, Commented Jun 20, 2014 at 5:15

Community · Accepted Answer · 2017-05-23 12:39:42Z

When using an insert cursor the inserted object may not be written to the feature class as soon as you call insertRow, Python is based on C and C uses filestream objects with windows buffering and aren't flushed until the OFstream::flush(); is called.. this means little from the Python point of view but still needs to be understood. It is best to dismiss the cursor, which will call the flush in its destructor.

Two methods can be used for this, first the with method (see Python with):

def onMouseDownMap(self, x, y, button, shift):
    xy = (x,y)
    with arcpy.da.InsertCursor(r'C:/temp/points.shp', ("SHAPE@XY")) as cursor:
        cursor.insertRow([xy])
    arcpy.RefreshTOC()
    arcpy.RefreshActiveView()

the older (to me anyway) method is the del statement (see Python del):

def onMouseDownMap(self, x, y, button, shift):
   xy = (x,y)
   cursor = arcpy.da.InsertCursor(r'C:/temp/points.shp', ("SHAPE@XY"))
   cursor.insertRow([xy])
   del cursor

   arcpy.RefreshTOC()
   arcpy.RefreshActiveView()

Either way will force your point to show and update the extent of the shapefile.

Stack Exchange Network

Add points to shapefile and display over map interactively using Python Add-Ins

1 Answer 1

Your Answer

Hot Network Questions

Add points to shapefile and display over map interactively using Python Add-Ins

1 Answer 1

Your Answer

Sign up or log in

Post as a guest

Related

Hot Network Questions