//global variables that can be used by ALL the function son this page. 
var inputs; 
var imgFalse = 'imagens/arvore/webgis_ckbox_inactive.gif'; 
var imgTrue = 'imagens/arvore/webgis_ckbox_active.gif'; 
var imgSemDados = 'imagens/arvore/webgis_ckbox_semdados.gif';

//this function runs when the page is loaded, put all your other onload stuff in here too. 
//function init() 
//{ 
//	//replaceChecks(); 
//} 

function replaceChecks()
{ 
	//get all the input fields on the page 
	inputs = document.getElementsByTagName('input'); 

	//cycle trough the input fields 
	for(var i=0; i < inputs.length; i++)
	{ 
		//check if the input is a checkbox 
        	if(inputs[i].getAttribute('type') == 'checkbox')
		{ 
			//obter class
			var sClass = inputs[i].className;
	
	        	//create a new image 
        		var img = document.createElement('img'); 
			//atribuir estilo
			img.className = 'arvImg';
             
	        	//check if the checkbox is checked
			//categorias sem dados têm outras definições
			if (sClass == 'tsd') { img.src = imgSemDados; }			
			else
			{
        	    		if(inputs[i].checked) { img.src = imgTrue; }
				else { img.src = imgFalse; } 

	            		//set image ID and onclick action 
        	   		img.id = 'checkImage'+i;
				//alert(img.id)

	            		//set image 
        	    		img.onclick = new Function('checkChange('+i+')');
			}

	        	//place image in front of the checkbox 
        		inputs[i].parentNode.insertBefore(img, inputs[i]); 
             	
	        	//hide the checkbox 
        		inputs[i].style.display='none'; 
		} 
	}
} 

//change the checkbox status and the replacement image 
function checkChange(i)
{ 
	if(inputs[i].checked)
	{ 
       		inputs[i].checked = '';
		//chamar o onclick da selectbox
		inputs[i].onclick(); 
        	document.getElementById('checkImage'+i).src=imgFalse; 
	}
	else
	{ 
        	inputs[i].checked = 'checked'; 
		//chamar o onclick da selectbox
		inputs[i].onclick(); 
        	document.getElementById('checkImage'+i).src=imgTrue; 
    	} 
} 

function changeImg(i)
{
	//alert(inputs[i] + "\n" + inputs[i].checked + "\n" + document.getElementById('checkImage'+i) + "\n" + i)

	if(inputs[i].checked) 
    	{ 
        	document.getElementById('checkImage'+i).src=imgTrue; 
    	} 
   	else 
    	{  
    		document.getElementById('checkImage'+i).src=imgFalse; 
    	} 
}