TIME LINE
The timeline controls the animation’s content in frames or/and layers. There are three main components of the timeline: Layers, Frames and the play head.
Frames: - In Flash, every animation’s time is divided into frames. On every frame, there can be a different animation’s position/appearance.
Layers: - The concept of layers in Flash is derived from its literal meaning. Layers are like strips stacked on top of each other. The layer on the top hides all the other layers below it (unless masking is done. See masking details below)
Play head: - When the animation runs on Flash, it runs as per defined by its frames. We see the animation defined from frame # 1 until the last frame defined. The play head indicates the current frame that is being displayed.
Using Frames: - First, Let me differentiate Frames with Key Frames as we will be using these terms together. Suppose your animation consists of 10 ms, it can be divided into five frames. Thus, a frame:
• Exhibits the specific state of an object
• Displays this state for some specified time.
A key frame is a frame in which you define a change in an animation. When you define two key frames such that the first one has a different object state (than the second one), Flash tweens or fills in the frames between the two key frames. For example, if you draw a circle on the first key frame while a rectangle on the next key frame which is 10 frames apart, Flash ensures a smooth conversion of the circle into rectangle.
The order in which frames and key frames appear in the Timeline determines the order in which they are displayed. You can see the complete description of frames at: See Frames Description.
Using Layers: - As discussed before, you can draw as many objects on one layer without affecting the objects on the other layers. You can also prioritize your layers to select which objects will appear at the top.
See the left part of the above image. There are four layers in it. The first layer “Actions” is without any folder. The next three are in the folder named “Folder”. The “Guide” layer is guided layer. On the top, there are three icons. The eye icon shows which layers can be displayed on your stage. If you click on the box next to the layer name in the eye column, that layer will not be displayed as long as you are editing the other layers. The next is the Lock option. Choosing it will lock (prevent) a particular layer for editing the layer objects. Below to the layers are three icons. The first one is “Insert Layer”: Clicking on it will create a separate layer. Double click this layer to choose its name. The next one is “Guided Layer” icon. Clicking here will create a guided layer. The last one is “Insert Folder”: Choosing this option will create a folder in which you can put the other layers. Folders can be prioritized in appearance in the same way as layers do.