C.2. Controlling Movie Clips
In Chapter 13, "Movie Clips", we learned how to control clips using Flash 5 techniques. Here we consider the equivalent Flash 4 techniques.
Prior to Flash 5, we would execute special Movie Clip Actions to control a movie clip. We would say "Tell the clip named eyes to play," using the following:
Begin Tell Target ("eyes") Play End Tell Target
But as of Flash 5, movie clips can be controlled more directly, through built-in methods. For example:
Similarly, to access the built-in properties of a movie clip prior to Flash 5, we would use explicit property-getting and property-setting commands, such as:
GetProperty ("ball", _width) Set Property ("ball", X Scale) = 90
As of Flash 5, we can retrieve and set a movie clip's properties using the dot operator, just as we would access the properties of any object:
ball._width; ball._xscale = 90;
Prior to Flash 5, to access variables inside a movie clip, we used a colon to separate the clip name from the variable name:
Set Variable: "x" = myClip:myVariable
As of Flash 5, a variable in a movie clip is simply a property of that clip object, so we now use the dot operator to set and retrieve variable values:
myClip.myVariable = 14; x = myClip.myVariable;
Finally, prior to Flash 5, we would access nested levels of movie clips using a directory-tree metaphor of slashes and dots:
Because movie clips are object-like data as of Flash 5, we can store one clip as a property of another clip. We, therefore, use the dot operator to access so-called nested clips, and we use a clip's reserved _ parent property to refer to the clip that contains it:
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