lib/Ext/field/Spinner.js
function(newComponent) {
        this.callParent(arguments);

        var cls = this.getCls();

        if (newComponent) {
            this.spinDownButton = Ext.Element.create({
                cls : cls + '-button ' + cls + '-button-down',
                html: '-'
            });

            this.spinUpButton = Ext.Element.create({
                cls : cls + '-button ' + cls + '-button-up',
                html: '+'
            });

            this.downRepeater = this.createRepeater(this.spinDownButton, this.onSpinDown);
            this.upRepeater = this.createRepeater(this.spinUpButton,     this.onSpinUp);
        }
    }
function(newComponent) {
        this.callParent(arguments);

        var cls = this.getCls();

        if (newComponent) {
            this.spinDownButton = Ext.Element.create({
                cls : cls + '-button ' + cls + '-button-down',
                html: '-'
            });

            this.spinUpButton = Ext.Element.create({
                cls : cls + '-button ' + cls + '-button-up',
                html: '+'
            });

            this.downRepeater = this.createRepeater(this.spinDownButton, this.onSpinDown);
            this.upRepeater = this.createRepeater(this.spinUpButton,     this.onSpinUp);
        }
    }
Updates the {@link #component} configuration