[JS] Probleem met pop-ups.

function show_popup() {
	window.open("test.php", "Test", 'toolbar=0, menubar=0, scrollbar=0, resizable=0, width=400, height=200, location=0');
show_popup();
}

function show_popup() {
	window.open("test.php", "Test", 'toolbar=0, menubar=0, scrollbar=0, resizable=0, width=400, height=200, location=0');
show_popup();
}

function show_popup() {
  window.open("test.php", "Test", 'toolbar=0, menubar=0, scrollbar=0, resizable=0, width=400, height=200, location=0');
}

function show_popup() {
  window.open("test.php", "Test", 'toolbar=0, menubar=0, scrollbar=0, resizable=0, width=400, height=200, location=0');
}

show_popup();

show_popup();

<script type="text/javascript">
var theWindow = '';
function popup(theLocation, theName, theWidth, theHeight)
{
    theTop = (screen.height) ? (screen.height - theHeight) / 2 : 100;
    theLeft = (screen.width) ? (screen.width - theWidth) / 2 : 100;
    
    theSettings = 'width = ' + theWidth + ',';
    theSettings += 'height = ' + theHeight + ',';
    theSettings += 'top = ' + theTop + ',';
    theSettings += 'left = ' + theLeft + ',';
    theSettings += 'scrollbars = yes,';
    theSettings += 'location = no,';
    theSettings += 'directories = no,';
    theSettings += 'status = no,';
    theSettings += 'menubar = no,';
    theSettings += 'toolbar = no,';
    theSettings += 'resizable = no,';
    
    theWindow = window.open(theLocation, theName, theSettings);
    
    theWindow.focus();
}
</script>
<a href="javascript:popup('blaat.php','popup','500','300');">LinkText</a>

<script type="text/javascript">
var theWindow = '';
function popup(theLocation, theName, theWidth, theHeight)
{
    theTop = (screen.height) ? (screen.height - theHeight) / 2 : 100;
    theLeft = (screen.width) ? (screen.width - theWidth) / 2 : 100;
 
    theSettings = 'width = ' + theWidth + ',';
    theSettings += 'height = ' + theHeight + ',';
    theSettings += 'top = ' + theTop + ',';
    theSettings += 'left = ' + theLeft + ',';
    theSettings += 'scrollbars = yes,';
    theSettings += 'location = no,';
    theSettings += 'directories = no,';
    theSettings += 'status = no,';
    theSettings += 'menubar = no,';
    theSettings += 'toolbar = no,';
    theSettings += 'resizable = no,';
 
    theWindow = window.open(theLocation, theName, theSettings);
 
    theWindow.focus();
}
</script>
<a href="javascript:popup('blaat.php','popup','500','300');">LinkText</a>