How to do this Smooth Animation frame by frame like in unity

Is there any way to do a smooth animation in unity for a simple 2d stick figure like in adobe flash ? drawing frame by frame stick figure animation in adobe flash is easy and nice, but i found it really hard to do a stick figure animation with rig in unity, i tried to make an animation similar to this in the following video but i couldnt do it in unity, so guys can you show/tell me how to do this kind of animation in unity ?

No. Unity3D doesn’t have any built-in functions to do such a thing.
You can try to find some Assets on the Asset Store to do the job. No guarantee there is one though.

Yes, you can use mechanim to do it.

You will need a sprite with separate frames animating its walk cycle.

You can use the animator to line up the animation using the individual sprite frames.

Then you can use boolean triggers in mechanim to switch between animations.