movable header

app.js

var win = Ti.UI.createWindow();

// image found at
// http://f.cl.ly/items/3F2Z0j112l3r0x2Z0215/background.png

var bgImage = Ti.UI.createImageView({
	width:320,
	height:320,
	image: 'background.png',
	top:-100
});

var headerView = Ti.UI.createView({
	height: 100,
	backgroundColor: 'transparent'
});

win.add(bgImage);

var table = Ti.UI.createTableView({
	headerView:headerView,
	backgroundColor:'transparent',
	data: [
		{title: 'Hello World', backgroundColor: 'white'},
		{title: 'Hello World', backgroundColor: 'white'},
		{title: 'Hello World', backgroundColor: 'white'},
		{title: 'Hello World', backgroundColor: 'white'},
		{title: 'Hello World', backgroundColor: 'white'},
		{title: 'Hello World', backgroundColor: 'white'},
		{title: 'Hello World', backgroundColor: 'white'},
		{title: 'Hello World', backgroundColor: 'white'},
		{title: 'Hello World', backgroundColor: 'white'},
		{title: 'Hello World', backgroundColor: 'white'},
		{title: 'Hello World', backgroundColor: 'white'},
		{title: 'Hello World', backgroundColor: 'white'},
		{title: 'Hello World', backgroundColor: 'white'},
		{title: 'Hello World', backgroundColor: 'white'},
		{title: 'Hello World', backgroundColor: 'white'},
		{title: 'Hello World', backgroundColor: 'white'},
		{title: 'Hello World', backgroundColor: 'white'},
		{title: 'Hello World', backgroundColor: 'white'},
		{title: 'Hello World', backgroundColor: 'white'}
	]
});

win.add(table);

win.open();

table.addEventListener('scroll', function(e){
	var offsetY = e.contentOffset.y;
	var top = -120;
	if(offsetY < 0){
		top -= offsetY / 2;
	} else {
		top -= offsetY;
	}
	bgImage.top = top;
});