background based on my data

How the set the background of the cells based on myData?
Tried this but doesn't work

obj.defineCellProperty("background-color", function(col,row){ 
 
    var value = (myData); 
    var color = "";
    if (value > 1) {color = "red" ;}
     
    return color; 
});  
obj.getCellTemplate().setStyle("background-color", function(){return this.getControlProperty("background-color"); });

Important: I do not want to fill the cells with the data. I only want to show a different background color based on the data in myData.

Thanks in advance. Mark