var focusObjValue = 0;

function GetBeforeChangeValue(obj){
	if (isNaN(obj.value))
		focusObjValue = 0;
	else{
		if (String(obj.value).length <1)
			focusObjValue = 0;
		else
			focusObjValue = obj.value;
	}
}

function CalcTotalByAmtObj (strChk, objAmt){
	var strAmt = objAmt.value;
	var objChk = MM_findObj(strChk);
	//need to minus the current amount
	var objTotal = MM_findObj('totalamt');
	if (parseInt(objTotal.innerHTML) > 0){
		var crntTotal = parseInt(objTotal.innerHTML);
		objTotal.innerHTML = crntTotal-parseInt(focusObjValue);
	}
	CalcTotal(objChk, strAmt);
	focusObjValue = 0;
}

function CalcTotalByChkObj (objChk, strAmt){
	var objAmt = MM_findObj(strAmt);
	if (parseInt(objAmt.value))
		CalcTotal(objChk, objAmt.value);
}

function CalcTotal (objChk, strAmt){
	var objTotal = MM_findObj('totalamt');
	var crntTotal = parseInt(objTotal.innerHTML);
	if (objChk.checked){ //checked means add the amount to the total
		objTotal.innerHTML = crntTotal+parseInt(strAmt);
	}
	else{ //subtract the ammount
		objTotal.innerHTML = crntTotal-parseInt(strAmt);
	}
	if (parseInt(objTotal.innerHTML) < 0)
		objTotal.innerHTML = '0';
}

function OnSubmitForm(){
	var objTotalAmt = MM_findObj('totalamt');
	var objSubject = MM_findObj('CMDSubject');
	objSubject.value += " - Total: $" + objTotalAmt.innerHTML;	
	
	return true;
}