js监听页面渲染完成事件

document.addEventListener('DOMContentLoaded', function() {
    console.log('DOM fully loaded and parsed');
});

window.onload = function() {
    console.log('All resources fully loaded');
};

function checkRenderComplete() {
    if (performance.timing.loadEventEnd > 0) {
        console.log('Page render complete');
    } else {
        requestAnimationFrame(checkRenderComplete);
    }
}
requestAnimationFrame(checkRenderComplete);

let observer = new MutationObserver(function(mutationsList, observer) {
    let allElementsLoaded = true;
    document.querySelectorAll('img').forEach(img => {
        if (!img.complete) {
            allElementsLoaded = false;
        }
    });
    if (allElementsLoaded) {
        console.log('All elements loaded');
        observer.disconnect();
    }
});

observer.observe(document, { childList: true, subtree: true });