mutation observer example

mutation-observer-example.js

const observer = new MutationObserver((mutations) => 
  mutations.forEach((mutation) => 
    console.log(`New layout: ${mutation.target.getAttribute('data-layout')}`)
  )    
);

observer.observe(document.body, { 
  attributes: true,
  attributeFilter: ['data-layout'] 
});


// they will print the last value (large) due to dom is slower obv
document.body.setAttribute('data-layout', 'small');
document.body.setAttribute('data-layout', 'medium');
document.body.setAttribute('data-layout', 'large');