PROBLEM
When a custom basemap is added to the Viewer for Flex application with a different tiling schema, the basemaps cannot display on top of each other.
ArcGIS Online basemaps are tiled services with a defined tiling scheme and fixed levels of detail. If the custom basemap is a dynamic service, a conflict occurs that prevents the ArcGIS Online basemaps from displaying when the user selects a basemap.
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