例如：

var sysMan:SystemManager = Application.application.systemManager;

sysMan.removeEventListener(FlexEvent.IDLE, timeoutHandler);

// timeout after twenty seconds

public var timeout:Number = 20000;

private var timeoutTotal:Number = 0;

private var timeoutLastCall:Number;

public var sessionExpired:Boolean = false;

public var enableTimeout:Boolean = true;

private function timeoutHandler(event:FlexEvent):void

{

// get current time

var curTime:int = getTimer();

var timeDiff:int = 0;

if (isNaN(timeoutLastCall)) {

timeoutLastCall = curTime;

}

timeDiff = curTime - timeoutLastCall;

timeoutLastCall = curTime;

// if time has passed since the idle event we assume user is interacting

// reset time total - otherwise increment total idle time

if (timeDiff > 1000) {

timeoutTotal = 0;

}

else {

// update time

// the status field will not be updated unless the application is idle

// it is only display a countdown for learning purposes

timeoutTotal += 100;

status.text = "Timeout in " + String(Number((timeout - timeoutTotal)/1000).toFixed(0)) + " seconds";

}

// if the total time of inactivity passes our timeout

// and the session already hasn't expired then logout user

if (timeoutTotal > timeout && !sessionExpired) {

// logout user

// or set flag

sessionExpired = true;

status.text = "timeout threshold has been reached";

//当时间超过之后执行的语句

sessionTimeoutHandler();

}

}