var expanded = false;
var originalHeaderHeight;
var button;

function setButtonExpand() {
    button.innerHTML = '↓ Expand header';
}

function setButtonShrink() {
    button.innerHTML = '↑ Shrink header';
}   

function expandHeader(button) {
    
    var newHeight;
    var callBackFunction;
    
    if(expanded) {
        newHeight = originalHeaderHeight;
        callBackFunction = setButtonExpand;
    }
    else {
        newHeight = photoHeight;
        callBackFunction = setButtonShrink;
    }
    
    $('topBar').morph({height:newHeight}, {afterFinish:callBackFunction});
    
    expanded = !expanded;
}

function setup() {
    originalHeaderHeight = $('topBar').getStyle('height');
    button = $('headerToggle');
}

window.onload = setup;