Wait till next page fully loads

Question

I have page 1 and page 2, A button in page 1 takes a user to page 2. I want a javascript to wait till page 2 has fully loaded before displaying it when the user clicked the button in page one, In between I need to put loading gif, so that visitor will know that something is loading. How can I achieve that using pure javascript?

No jQuery please.

EDIT: The javascript has to be pasted in page one, so that the button would be the trigger, do note that we can't load page 2 in div as some might suggest to load page two in div, then read if page two is fully loaded then display div.

Answer 1

window.onload可能就是您想要的

Answer 2

document.addEventListener("DOMContentLoaded", function(event) {
    //Your code
});