MACROMEDIA FLASH 8-LEARNING ACTIONSCRIPT 2.0 IN FLASH, Руководство пользователя

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76 Data and Data Types
//display the label
welcome_lbl.visible = true;
}
};
submit_button.addEventListener("click", btnListener);
For more information, see “Using functions in Flash” on page 214 and “About logical
operators” on page 194 .
MovieClip data type
Movie clips are symbols that can play animation in a Flash application. They are the only data
type that refers to a graphic element. The MovieClip data type lets you control movie clip
symbols using the methods of the MovieClip class.
You do not use a constructor to call the methods of the MovieClip class. You can create a
movie clip instance on the Stage or create an instance dynamically. Then you simply call the
methods of the MovieClip class using the dot (
.
) operator.
Working with movie clips on the Stage
The following example calls the
startDrag()
and
getURL()
methods for different movie clip instances that are on the Stage:
my_mc.startDrag(true);
parent_mc.getURL("http://www.macromedia.com/support/" + product);
The second example returns the width of a movie clip called
my_mc
on the Stage. The targeted
instance must be a movie clip, and the returned value must be a numeric value.
function getMCWidth(target_mc:MovieClip):Number {
return target_mc._width;
}
trace(getMCWidth(my_mc));
Creating movie clips dynamically Using ActionScript to create movie clips dynamically is
useful when you want to avoid manually creating movie clips on the Stage or attaching them
from the library. For example, you might create an image gallery with a large number of
thumbnail images that you want to organize on the Stage. Using
MovieClip.createEmptyMovieClip()
lets you create an application entirely using
ActionScript.
To dynamically create a movie clip, use
MovieClip.createEmptyMovieClip()
, as shown in
the following example:
// Creates a movie clip to hold the container.
this.createEmptyMovieClip("image_mc", 9);
// Loads an image into image_mc.
image_mc.loadMovie("http://www.helpexamples.com/flash/images/image1.jpg");