Macromedia Studio 8 [Electronic resources] : Training from the Source نسخه متنی

Creating Temporal Structure with Keyframes and Labels

The movie is 96 frames long, and therefore it lasts 8 seconds. Currently the movie doesn't actually do anything. As mentioned earlier, to make things happen in Flash, you create keyframes and change the appearance, location, or presence of the objects within the frames on the stage.

In this task, you'll work on the overall temporal structure of the movie, by making the timeline more clearly reflect the three screens that represent the sections of our movie. As a part of this process, you'll insert two keyframes in the labels layer, which you'll use to create bookmark-like labels to demarcate those portions of the timeline. The first of the two keyframes you'll create will identify the frame where the second screen begins, and the second keyframe you'll create will identify where the third screen begins. You don't have to worry about creating a keyframe for the first screen, because the first frame of every layer is a keyframe.

Keyframes are represented as a frame with a circle. The circle is hollow as long as the keyframe has no visible content (such as vector art, a digital photograph, or some text). A keyframe without content is called a blank keyframe. A keyframe with content has a solid black circle, and the circle appears against a shaded background.

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You add a keyframe to Frame 47 because an animation is going to separate the first and second screens, and it will take almost 4 seconds.

The contents need to change again in Frame 67, at which point the third screen should become active.

In the next lesson, you'll stop this Flash movie after it plays through Frame 47. The movie will also stop in Frame 67, where the third screen appears. To proceed, the user will have to click a button. Giving buttons this functionality requires some scripting. Although the script needed for this kind of interactivity is quite simple, you'll need to specify where the various screens are in the timeline. Because each screen is (or will be) associated with a given keyframe (Frames 1, 47, and 67), you'll need a means of pointing to those frames as having special significance.

You can achieve this goal in Flash by giving the desired frames frame labels, which are like bookmarks that enable Flash to jump to the desired frame. You'll add some frame labels next.

The movie has three primary screens, so you'll label each one in turn.

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If you can't see the Property inspector, choose Window > Properties.

In the timeline, you'll see a red flag added in Frame 1 of the labels layer, which indicates that this frame is labeled. The red flag is accompanied by the frame label.

As before, the red flag and label appear in the timeline.