How should I add a tooltip to an ExtJS Component?

Question

I'm making an ExtJS Component, and I want it to use a QuickTips tooltip. If I make an element using DomHelper, I can set a tooltip, no sweat. If, however, I make a Component, like

new BoxComponent({
  qtip: "This is a tip"
});

nothing happens. I've also tried naming the property "tooltip", but no luck. Is there a right way to do this? The hack I have in place now that works is

new BoxComponent({
  qtip: "This is a tip",
  listeners: {
    rendered: function(c){
      Ext.QuickTips.register({
        target: c.getEl(),
        text: c.qtip
      }
    }
});

I feel like that can't be right. I guess I could just extend Component to do that automatically, but it seems like a common enough case that I should be able to do it without poking under the hood like this.

Answer 1

In ExtJS 4.2.1, I am able to add a tip to a checkbox this way:

new Ext.form.field.Checkbox({
  ...
  tip: 'This is a tip',
  listeners: {
    render: function(c) {
      Ext.create('Ext.tip.ToolTip', {
        target: c.getEl(),
        html: c.tip 
      });
    }
  });