Problem

Put the wrapper paper-dialog to the center of the screen

Solution

        
     
Are you sure
    
     
      Close
         
     
      Yes    
     
    

The javascript code

/**                 * this function is critical for position center                 * even the order is very important                 *                 * resizeHandler need to be called, like trigger a windows resize event                 *                 * max-width of sizing target will not be override, so please call it after resizeHandler                 **/function positionCenter(event) {    event.target.resizeHandler();    event.target.sizingTarget.style['max-width'] = '100%';}

The reason is if you set max-width first, resizehandler will set it back