setting MapDocument.activeView causes existing layers to disappear

Question

I have one mxd with two data frames ['Layers', 'New Data Frame'] with layers in them. If Layers is active and I use the lines below in the command line window:mxd = arcpy.mapping.MapDocument('Current')
df = arcpy.mapping.ListDataFrames(mxd, 'New Data Frame')[0]
mxd.activeView = df

New Data Frame is made active and I see the layers.

If use the same commands in a geoprocessing script, the layers are removed from the data frame before it is made active.

Does anyone know what's going on?

JeffreyBarrette · Answer

This issue will be addressed in service pack 3.

EvanThoms · Answer

and Jason! Thank you for the explanation.

EvanThoms · Answer

Excellent! Thank you Jeffery.

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