QGIS – Automating the Creation of Multiple Maps with Different Layers on Same Location in QGIS

Question

I was wondering if it is possible in QGIS 3.2 to cycle through different layers.

For example, I have a workspace open with 3 raster layers (A, B and C). I would like to create 3 maps:

• Map A with Layer A and Legend A
• Map B with Layer B and Legend B
• Map C with Layer C and Legend C

The only difference in all these maps is the switching of the raster layer and the legend of the layer. Everything else is the same.

I found a similar question before but it appears to be unanswered.

Creating atlas of different layers on the same place (QGIS)

Answer 1

You can set layer visibility (in the layer symbology) based on an atlas variable. Your options for atlas variables are: @atlas_feature, @atlas_featureid, @atlas_geometry and @atlas_pagename.

In QGIS 3.0, use the atlas variable to control whether the layer is enabled.

For example, if your atlas pages are named Map A, Map B and Map C, set the visibility of the grid for Map A like so:

In QGIS 2.18 and earlier, "Enable layer" is not an option. Instead, use a similar method to control the layer transparency. Use this expression for data-defined transparency for Map A:

if(@atlas_pagename = 'Map A', 0, 100)

You can also write your own expressions to control layer visibility within the print composer.

Write an expression that outputs a list of map layer names separated by the | character. For example:

case 
  when @atlas_pagename = 'Map A' then 'layerone | layertwo | layerthree'
  when @atlas_pagename = 'Map B' then 'layerone | layertwo | layerfour'
  when @atlas_pagename = 'Map C' then 'layerone | layertwo | layerfive'
  else ''
end

---

This is how I knew how to format the list of map layer names.