throbbers = 0;

function startThrobber() {
	throbbers++;
	if (document.getElementById('stopedThrobber') != null) {
		document.getElementById('stopedThrobber').style.display = "none";
		document.getElementById('runningThrobber').style.display = "";
	}
}

function stopThrobber() {
	throbbers--;
	if (document.getElementById('stopedThrobber') != null && throbbers == 0) {
		document.getElementById('stopedThrobber').style.display = "";
		document.getElementById('runningThrobber').style.display = "none";
	}
}