Loading message not working

[Andy Lincoln]

Hi all,
I am a newbie in Extjs. I want to create a simple login form and before form is loaded want to show a loading message. To do so my code is as below :
this.items = [{
xtype: 'form',
listeners: {
show: function() {
this.loadMask = new Ext.LoadMask(this.body, {
msg: 'Loading. Please wait...'
});
}
},
frame: 'true',
items: [{
xtype: 'textfield',
name: 'email',
fieldLabel: 'Username',
//vtype: 'email',
allowBlank: false
}, {
xtype: 'textfield',
name: 'password',
fieldLabel: 'Password',
inputType: 'password',
style: 'margin-top:15px',
allowBlank: false,
//minLength: 8
}]
}];

Though the form loads it doesn't show the loading spinner before form loading...please help me in doing the same.

[mitchellsimoens]

Why not use the setLoading method on any component?