window.onload = init;

function init() {
	bmi = getObject("bmi");
	res = getObject("result");
	showBMIContent();
}

function showBMIContent() {
	bmi.innerHTML = "<div><input id='bmi_ge' type='text' name='gewicht'></div><div><input id='bmi_gr' type='text' name='groesse'></div><div><input type='button' onclick='calculateBMI()'></div>";
}

function calculateBMI() {
	result = getObject("bmi_ge").value / (getObject("bmi_gr").value * getObject("bmi_gr").value) * 10000;
	res.innerHTML = "<span style='font-size:36px'>" + result + "</span>";
}

function getObject(id) {
	return document.getElementById(id);
}

function hinweis() {
	alert("HALLO");
}