I will explain with an example:
I have 2 shp files for Tanzania.
Tanzania inland waters http://www.diva-gis.org/data/wat/TZA_wat.zip
Tanzania administrative boundaries http://gadm.org/data/shp/TZA_adm.zip
I open both shp files (TZA_wat.shp and TZA_adm0.shp) in Quantum GIS Desktop. I want to merge the layers : TZA_wat and TZA_adm0 and export/save both layers to one geojson file.
While I can do this for individual layers but not able to do this for both at once. I have written code to process geojson files but I get stuck at this step.
Is there a way to first merge both these .shp files to a single .shp file and then export/save as geojson?
update: Thanks to MappaGenosis, I used the Union option in QGIS and merged the two shp files (here) into one. I uploaded the file here in a zip if anyone wants to take a look. The zip has shp files and geojson file in it.