Game Development Reference
In-Depth Information
value representing a constant that we will define in the
Main.as
(
GameFrameWork.as
child class).
The constant will be the
id
string name of the element on the
scoreBoard
to update. The value
variable passed will be a string representing the value to show on the
scoreBoard
for the
corresponding
TextField
. It's constructed to allow the
Game
class instance and its associated
classes to update the
ScoreBoard
class instance without having to maintain a reference to it. This
allows the
Game
and its associated classes to remain decoupled from the
Main.as
and the basic
framework classes. We will see the same thing with the
levelInScreen
a little later. Why is the
ScoreBoard
part of the framework and not part of the
Game
class? We wanted to have the
ScoreBoard
be part of the
Main
class game framework because the
Game
class instance is not the
only object that might interact with the
ScoreBoard
. We do not implement it in this simple example,
but the
Main
might have other data such as a system-held high score, links out, or even a frame
counter in the
ScoreBoard
.
Why decouple the scoreboard from the game class instance? It is true that we could make calls
directly to the
ScoreBoard
from
Game
by using the root or parent attribute of the
Game
class. While
this is certainly possible, if we decouple the
Game
class from the
ScoreBoard
class, then the
Game
class will be reusable across multiple frameworks (even your own) with no need to use our
framework. The new framework would just need its own
ScoreBoard
or the
Game
would need to
implement its own.
The levelScreenUpdateListener function definition for
Main.as
The
levelScreenUpdateListener
allows the
Game
class to update the text on the
levelInScreen
.
Like the
scoreBoardUpdateListener
, the
levelScreenUpdateListener
function is used to pass
data from the
Game
class instance to the
levelInScreen
. When the
Game
class updates the level
value using its own
newLevel
function, the
levelInScreen
must also update its text so the correct
level number will be shown on the screen during the
systemLevelIn
function. The predefined
default
String
variable,
levelIntext
will be combined with the passed in value:
levelInScreen.setDisplayText(levelInText + e.text);
The gameOverListener function definition for Main.as
The
gameOverListener
listens for the
Game.GAME_OVER
simple custom event and then changes the
framework state accordingly.
When the
Game
class instance fires off the
GAME_OVER
simple custom event, the
Main
listens for it
and runs this function. It cleans up all of the game-related listeners by removing them and then
changes state to the
STATE_SYSTEM_GAME_OVER
state which was discussed earlier
The newLevelListener function definition for Main.as
The
newLevelListener
listens for the
Game.NEW_LEVEL
simple custom event and changes the state
accordingly.
The
newLevelListener
listens for the
Game
class instance to fire off the simple custom event,
NEW_LEVEL
. It then changes the
systemState
to the
STATE_SYSTEM_NEW_LEVEL
state.
