How to activate listeners in renderer function in a grid column

[honeyandbee]

I am using extjs 4 and I have a grid which shows a field name Approval. Here I have showed checkbox that will be checked when the grid is loaded if the value is true. But if the dataIndex value is fault only the checkbox will appear. Now I want that if I click on unchecked checkbox it will do a action using listeners. But I am not being able to do it. Can anyone please help me on this ? My codes are given below :

{
text: 'Approval',
dataIndex: 'approve',
flex: 1,
align: 'left',
renderer: function(value, metaData, record, row, col, store, gridView){
if(value == true) {
return '<input type="checkbox" checked="true" />';
}else{
return '<input type = "checkbox" />';
listeners: {
this.approve();
}
}
}
}

approve: function(){
alert('hi');
}

[mitchellsimoens]

First, why not use Ext.ux.CheckColumn that comes with the downloaded zip?