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I have installed the traceDigitize tool from the experimental repository in QGIS 1.9.0 Lisboa. My understanding of the tool is that you have to:

  1. Add 2 layers to QGIS Desktop. My empty shapefile to which I will edit and a polygon file of an object I want to trace.
  2. Set Snapping Options on the polygon file
  3. Activate the 'trace Edit' tool and move my cursor to the polygon I created until it snaps
  4. Hold ctrl button and begin tracing.

It seems to be tracing along the polygon, but when I right click to end the edit I get an error message:

enter image description here enter image description here

I'm not sure what this means. I know this plugin is experimental, but the one thread I found about this tool implies it works. Am I doing something wrong?

Thanks, Mike

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up vote 2 down vote accepted

This plugin does not work with QGIS 1.9 (master) since the srs() method has been removed and replaced by the crs() method.

See the API documentation:

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Is the method still relatively the same? Could I just change the call from layers.srs() to – Mike Apr 11 '13 at 15:45
Sure, give it a try. It returns the same object as the previous srs() method. – gsherman Apr 11 '13 at 16:08 doesn't look like either one of those modules are installed. I'm using the OSGEO4w installer to install QGIS 1.9. Is there a specific library I should be installing? I can't figure out which one it is when I scroll through all the libs. – Mike Apr 11 '13 at 16:38
Edit line 282 in, changing layerEPSG = layer.srs().epsq() to layerEPSG= The path to it is shown in your screenshots posted with your original question – gsherman Apr 11 '13 at 18:51
Thanks for helping. That's the update I made. It's now telling me that 'QgsCoordinateReferenceSystem' object has no attribute 'epsg'. Any idea if they replaced/renamed this object as well in the crs() Method? – Mike Apr 11 '13 at 19:57

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