function changeIDStatus(material, num) {
  if (num <= 1) return;
  var childElements=document.getElementsByName("id"+material);
  if (childElements.length>0) {
    for (i=0; i<childElements.length; i++) {
      childElements[i].disabled=false;
    }
    childElements[0].checked=true;
    document.getElementById("materialID").value=childElements[0].value;
  } else {
    document.getElementById("materialID").value="0";	
  }
  var myButton=document.getElementById("checkAll"+material);
  if (myButton!=null) {
    myButton.disabled=false;
  }
  
  for (j=0; j<num; j++) {
    if (j != material) {
       var otherElements=document.getElementsByName("id"+j);
       for (i=0;i<otherElements.length; i++) {
         otherElements[i].checked=false;
         otherElements[i].disabled=true;
       }
       var otherButton=document.getElementById("checkAll"+j);
       if (otherButton!=null) {
         otherButton.disabled=true;
       }
    }
  }
}

function setValue(attribute, aValue) {
  var element=document.getElementById(attribute);
  element.value=aValue;
}

function setIDValue(id, aValue) {
  var idElement=document.getElementById("id"+id+aValue);
  var element=document.getElementById("materialID");
  if (idElement.checked) {
    if ((element.value==null) || (element.value=="") || (element.value=="0")) {
      element.value=aValue;
    } else {
      if (element.value.substring(element.value.length-1,element.value.length)<aValue) {
        element.value+=aValue;	
      } else {
        for (i=0;i<element.value.length;i++) {
          if (element.value.substring(i,i+1)>aValue) {
            element.value=element.value.substring(0,i) + aValue + element.value.substring(i,element.length);
            break;
          }	
        }
      }
    }
  } else {
    if (element.value.length==1) {
      if (element.value==aValue) {
        idElement.checked=true;
        alert("Please choose another ID before you uncheck this one since we need at least one ID for this material!")
      }
      else return;
    } else {
      var pos=element.value.indexOf(aValue);
      if (pos<0) return;
      element.value=element.value.substring(0,pos) + element.value.substring(pos+1,element.value.length);
    }
  }
}

function checkAll(materialNO,ids) {
  for (i=0;i<ids.length;i++) {
    var element=document.getElementById("id"+materialNO+ids.substring(i,i+1));
    element.checked=true;
    setValue("materialID", ids); /* not setIDValue funtion */
  }
}

function enableUnits() {
  for (i=1;i<=3;i++) {
    var unitElement=document.getElementById("unit"+i);
    if (unitElement.disabled) {
      unitElement.disabled=false;
    }
  }	
}

function chooseEv() {
  for (i=1;i<=4;i++) {
    var unitElement=document.getElementById("unit"+i);
    if (i==4) {
      unitElement.checked=true;	
      setValue("unitType", "4");
    } else {
      unitElement.disabled=true;	
    }	
  }
}