renderTo and applyTo

dear
I am new to ext, I don't understand the difference between "renderTo", "applyTo" and "contentEl", the three config value, can use the node of dom, how situation for me to use it?

best regards
ives

• renderTo renders the Component into the specified existing element.
  
• applyTo uses the specified alement as the main elementof the Component. A Component created using applyTo does not need rendering - its main element already exists.
  
• contentEl is only for Panels. It simply moves the specified element into the body of the Panel when the Panel is rendered to use... as the content!

i added the config "renderTo: Ext.get('tree-div')" and it just does not work. tree-div is the id of a div in a form in body of the page.
I am mixed up!
help me please.

use Ext.Element.get('tree-div')

Is this the body of a FormPanel? In that case you shouldn't be using renderTo at all!!!

Instead, you should be specifying the component as one of the items of the formpanel.

partial code below

var ImagePanel = new Ext.Panel({
id: 'images-view',
frame: true,
width: 500,
height: 1000,

autoHeight: false,
layout: 'auto',
align: 'middle',
title: 'View image',
bodyStyle:'overflow:visible',
bodyCfg:
{
tag: 'div',
cls: 'x-print-body' // Default class not applied if Custom element specified
},
bwrapCfg:
{
tag: 'div',
cls: 'x-print-bwrap' // Default class not applied if Custom element specified
},
items: [tbUsers,pagingbar,datav]

})

// create window
var win = new Ext.Window({
id:'imginform-win'
,width: 640
, cls: 'printer'
,height: 600
,modal: true
,layout:'fit'
,border:false
,closable:true
,renderTo:imagepop
,frame:true
,items:ImagePanel
});


//ImagePanel.render('imagepop');


win.show();