How can I set a Shape Key value to be a driver's variable?

Question

I want a Shape Key's value to be driven by another shape key. But I don't know how to add a shape key value as a variable into a driver. I've selected single property and tried with Object or Mesh types.

Do I need to select another one?

Answer 1

• If you use an object in the Prop field, the path to the shape key is like this:

  data.shape_keys.key_blocks["Key 1"].value
  

• If you use a mesh, you don't have to put data there, so:

  shape_keys.key_blocks["Key 1"].value
  

  

• And if you use the Key Prop field with your key block there, then you can just use:

  key_blocks["Key 1"].value