Blit Scrolling in a Tile-Based World - The Essential Guide to Flash Games - page 426

We needed to also create an override function for the systemLevelIn function that would set the
alpha of the l evelInScreen back to 1 at the beginning of each STATE_SYSTEM_LEVEL_IN state.
override public function systemLevelIn():void {
levelInScreen.alpha = 1
super.systemLevelIn();

}

Updating the LevelInScreen text
We have added a new message to the levelInScreen . This message displays the number of
hearts that need to be collected during the level. To do this we first made sure to import in the
TextField class:
import flash.text.TextField;
Next, we added the heartsToCollect variable to the variable definition section.
private var heartsToCollect:TextField = new TextField();
In the init function, we have set the defaultTextFormat of the heartsToCollect field to be the
same as the screen text.
heartsToCollect.defaultTextFormat = screenTextFormat;
heartsToCollect.width = 300;
heartsToCollect.x = 50;
heartsToCollect.y = 200;
The heartsToCollect TextField also needs to be added to the levelInScreen 's display list:
levelInScreen.addChild(heartsToCollect);
We also added an event listener into the init function that will listen for a new custom event
class called CustomEventHeartsNeeded . When this event is dispatched, the number of hearts the
player needs to collect for the level will be sent along with it.
game.addEventListener(CustomEventHeartsNeeded.HEARTS_NEEDED, heartsNeededListener,

false, 0, true);
The heartsNeededListener function was also added to Main.as :
private function heartsNeededListener(e:CustomEventHeartsNeeded):void {
heartsToCollect.text = "Collect " + e.heartsNeeded + " Hearts";
}
This function will change the heartsToCollect.text to the passed in value (from the custom Event)

Increasing the game Frame Rate
As we transition into games that require more and more system resources, we are going to
experiment with using the Timer class to create a frame rate different than the Stage frame rate
( 30 ).We are going to set the frame rate to 40 for this game. Remember that the updateAfterEvent
function call inside the GameFrameWork 's game loop will help smooth out the look of the screen
updates when we choose a frame rate higher than the Stage frame rate. In the next chapter, will
we create a new type of timer that will really push the limits of the Stage frame rate.
frameRate = 40;