A GIS Top Tip: Using different label classes at different zoom levels in ArcGIS Online map viewer
In ArcGIS Online map viewer you can use several different types of label at the same time. These types are called “label classes” and each can have different characteristics.
Why is this useful?
Label classes can be useful if you want to vary the information shown in a label depending on the zoom level of the interactive map.
For example, you could have the name of a town visible at a province-level but have the town name and population count show at a higher district-level zoom.
Not only can label classes be used to vary the level of information available in a label, they can also be used to vary the styling of that information too.
In the example below I have duplicated the label class three times. In each copy I have changed the “visible range” of each of those classes to cover different levels of zoom and then changed the font size of each, increasing it as I increase the zoom.
What’s the effect for the end user?
The effect this has for the end user is that, as they zoom the map in, the label’s font size increases to approximately match the level of zoom. Without this the label would continue to have the same font size regardless of zoom level (meaning the map would be incredibly cluttered with large labels, or difficult to read with small labels at different zoom levels).
The images below show how the label classes set up above manifest on the final map:
Are you confounded by labels? Are you wanting to show geographic complexity on a map? If so, we might be able to help. Either send us a request for support or come for an informal chat at our weekly surgery space — the details for both are on our RedRoom page.
