Test Case Boilerplate

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HTML

<div id="divA"><div id="divB">This is a text.</div></div>

CSS

#divA { height:300px; background:red; }
#divB { width:100px; height:100px; background:yellow; position:absolute; }

JavaScript

$(window).unbind("resize.divlayout").bind("resize.divlayout", function() {
  console.log('window-resize');
  reposition();
}).trigger("resize.divlayout");

function reposition() {
  $("#divA").unbind('resize.divlayout').bind('resize.divlayout', function() {
    console.log('divA-resize');
    //$("#divB").css("top", $("#divA").height() / 2 - $("#divB").height() /2 + "px");
  }).trigger('resize.divlayout');
}