Flash MX 2004 Games : Art to ActionScript

Flash MX 2004 Games
27 platform = "";
28 initAction(STOPRIGHT);
Listing 17.3
In the initialization section the values of certain constants are defined so that we can write
‘WALKLEFT’ in the code rather than ‘11’. When you are reading through the code it is much
easier to understand if you use names in this way rather than numbers. To facilitate easier debugging
the initialization also creates a string array that contains the names of the possible actions.
Using this array we can get the name of an action using the code:
actionNames[action];
actionNames[WALKRIGHT]
would return ‘WalkRight’.
Now we will look at the functions defined on frame 1.
‘userAction’ is called by the keyboard reader in the onClipEvent for the cat. A ‘switch’ statement
is used to select which code to run.
1 //===============userAction========================================
2 //This is called by the onClipEvent of the Cat instance
3 //parameters=======================================================
4 //index Possible values WALKRIGHT, WALKLEFT and JUMP
5 //=================================================================
6 function userAction(index) {
7 switch (index) {
8 case WALKRIGHT :
9 userWalkRight();
10 break;
11 case WALKLEFT :
12 userWalkLeft();
13 break;
14 case JUMP :
15 userJump();
16 break;
17 case HALT :
18 if (action == WALKLEFT) {
19 initAction(STOPLEFT);
20 } else if (action == WALKRIGHT) {
21 initAction(STOPRIGHT);
22 }
23 break;
24 }
25 }
Listing 17.4
264