Let object follow joined path Suppose I create two paths A and B, then select both paths and join them using Ctrl+J creating AB. I then want a cube to follow the joined path AB, that is first along A, then jump to and follow B. 



I add a "Follow Path" constraint to the cube and set keyframes for the Evaluation Time of the path. If I then animate however, the cube only follows A, as if A and B would not have been joined.

How to fix this? Obviously I could animate A and B separately but it would require more work and might get tedious if I had more paths than two and need to figure out how long each individual path is to let the cube traverse each path with the same speed.

Edit

Another path could look more complex like this:



Currently I model this to be four paths (one outer rectangle and three traversing straight paths) and control the cube with Keyframing the Evaluation Time and Influence properties. If I want the cube to follow the complete path (that is, all four paths) with the same speed however, I need to calculate how long each path is and model the evaluation time correctly. This is tedious...
You can use these 2 ways to make the mesh follow path which isn't contiguous.

Making the path contiguous

This way assumes keyframing either the Evaluation time property of the curve:



or the Fixed Position option of the Follow Path constraint.



You set the keyframes so the animated mesh jumps from one curve part to another.



The mesh will now jump over the connection of the curves.



Adding several Follow Path Constraints

You can leave curves as they are, and add adjacent quantity of the Follow Path constraints, animating both Fixed Position and Influence options. 
For more details see How to make an object follow a complex curve