I'm not very familiar with animations but as far as I know, most of the animations are done frame by frame. For example animating a character walking etc. However, let's imagine this scene:
There's a man coming from the left towards the sign. It's easy to animate this. But when he comes to the sign, he picks it up and starts waving with it. Now this is something I don't know how to do. What is generally the recommended way to do this kind of animation (two separate objects)? Specifically we're talking about android live wallpaper here (probably made with libgdx but I can use anything if it's better for me).