How add loading mask

[lukilooks]

hi, i'm nubie try to learn sencha touch, now i'm using v.1.1.1
i have list menu, and when i tap a list, i want add loading mask before list content show

here it's a code for listener :

list.addListener('selectionchange', function (model, records) {
if (records[0]) {
mainScreen.setActiveItem(contentSidePanel, {type: 'slide', direction: 'right'});
contentSidePanel.update(records[0].data);
mainScreen.doLayout();
mainScreen.showingPage = true;
mainScreen.showingSplash = false;
}
});

thx b4 for all solution...

[mitchellsimoens]

Every component should have a setLoading method on it that takes true/false