Using the Bone Tool
The Bone Tool allows you to animate thinks effectively and quickly in Flash CS4. First you need a drawing on the stage which is on one layer. Once you have done your drawing, go to the Selection Tool and select the whole drawing. Go over to the Bone Tool and click it. If you have drawn a leg, for example, go to the top of the leg, click and drag down to the knee joint, and let go. Then click and drag to the foot. You will see red lines drawn and the box will look different to your normal bounding box.
You will also notice that there is another layer added above our layer, called Armature. This will allow flash to automatically animate your bone that you have just created. Now, how do you animate that joint. Go to the foot joint and click on it. A bone icon appears next to your cursor, that means you are near to your joint. If you click, hold and drag that joint, you will notice that the rest of the leg bones move just like a proper leg would do so, all automatically. If you release it, it snaps into place.
To animate go to your timeline and move ahead a number of frames, for example fifteen and Control Click on the Armature layer at that frame and select Insert Pose. Move the bone joint to the desired position and release. If you hit Enter to preview it, you will see that it has tweened those frames automatically and we do not have to do anything about it. It is all done for you. It is similar to tweening, but it is more automated and it is easier to use. The Bone Tool is really simple to use, and is very effective.