callback

by rana777

HTML

<div class='rana'>
  this is to rana1
</div>
<div class='rana'>
this is rana2
</div>
<div class='rana'>
this is rana3
</div>
<div class='rana'>
this is rana3
</div>
<div class='rana'>
this is rana3
</div>
<div class='rana'>
this is rana3
</div>
<div class='rana'>
this is rana3
</div>
<div class='rana'>
this is rana3
</div>
<div class='rana'>
this is rana3
</div>
<div class='rana'>
this is rana3
</div>
<div class='rana'>
this is rana3
</div>
<div class="sulav">
  I am Sulav Paudel.
</div>
<div class="sulav">
  I am Sulav Paudel.
</div>
<div class="sulav">
  I am Johnny.
</div>
<div class="sulav">
  I am Johnny.
</div>
<div class="sulav">
  I am Johnny.
</div>

JavaScript

//call back example
//lets do first without callback
var findNodes = function(callback){
	var i  = document.getElementsByClassName("rana").length;//big heavy
  var nodes =[];//stores the resule
  console.log(document.getElementsByClassName("rana")[0]);
 // nodes.push(document.getElementsByClassName("rana"));
 if(typeof callback !=="function"){
    callback = false;
 }
 var nodeFound ="";
 for(var j=0;j<i;j++){
   nodeFound = document.getElementsByClassName("rana")[j];
   //now callback
   if(callback){
      callback(nodeFound)
   }
    nodes.push(nodeFound);
    
 }
		return nodes;
};

var hide = function(nodes){
 var i=0,max=nodes.length;
 for(;i<max;i+=1){
    nodes[i].style.display = "none";
 }
}

var hide = function(node){
	node.style.display="none";
}
findNodes(hide);//hide is a callback