Exploring the Features of the Timeline
The Flash Timeline controls the flow, interactivity, and organization of the movie. The Timeline contains all the layers that are used in the movie, as well as all the frames and scenes used in the movie (see Figure 3.2). You can compare the Timeline to a calendar. A scene can be compared to a month and a frame or keyframe can be compared to a day. With a calendar, if you want to see what is happening on a certain day in a certain month, locate that day within the month. Same with the Timeline, if you want to see what is happening in a certain frame or keyframe in a certain scene of the movie, you would click that frame within the scene. The playback head advances to that frame and the contents of the frame display on the Stage. You will use this technique a lot as you develop your movie.
Note - When a new Flash document is opened, the Timeline appears with only one frame occupied and it contains a blank keyframe. The remainder of the frames in the Timeline are actually photoframes, segmented in groups of five. A photoframe is a blank holding space for you to create your frames and keyframes.
This analogy of comparing the Timeline to a calendar is very simple when truly compared to the functionality of the Timeline. A closer look at the Timeline reveals many other features and the functionality of the Timeline, such as layers (see Figure 3.3).
Layers are a fundamental building block for your movie. They help you organize your images as well as organize your animation. You can create as many layers as you want to help you keep track of your images and the animation. Click the Insert Layer button to add a new layer and click the Delete Layer button to delete a layer. Similar to Adobe Photoshop, you can also hide and lock layers, which enables you to focus on one layer's contents and not disturb any other layer's content. You can also show a layer and its contents in outline format, which can be useful for troubleshooting animation.
There are other features and buttons available on the Timeline (see Figure 3.4). These are the Onion Skin buttons, the Edit Scene button, and the Edit Symbols button. The onion-skinning feature is comprised of three buttons located on the bottom of the Timeline window. These features allow for the Stage contents to be converted into an outline view or dimmed view. You will find this feature excellent for fine-tuning animation or for tracing images. As you can see, the Timeline is essential for animation and has many features and the functionality for creating and troubleshooting animation.
Resizing the Timeline
You can resize the Timeline to allow for more or less viewing area of your Stage or to view all layers in your Timeline. The default size is spaced to show four layers, but you will find that your movies will consist of many more layers than just four. So, you need to be able to resize your Timeline to view these features. To do this, just grab the lower Timeline window border and drag up or down to resize the window (see Figure 3.5).
Hiding the Timeline
There might be times when you want to hide the Timeline so you can see your Stage in a full view. This can be accomplished through the menu command View, Timeline. After you hide the Timeline, you can display it again by choosing the menu command again. This command is a toggle switch that will toggle the Timeline between hidden and displayed.