a5d1703486
Since rendering updates moved to on-demand scheduling, observing a target no longer fires the initial intersection callback unless something else happens to request a frame. Kick the frame timer from observe() so the update-the-rendering steps run and deliver the initial entry.
27 lines
883 B
HTML
27 lines
883 B
HTML
<!DOCTYPE html>
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<style>
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#target {
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width: 100px;
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height: 100px;
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background: red;
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}
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</style>
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<script src="../include.js"></script>
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<div id="target"></div>
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<script>
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asyncTest(done => {
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// Calling observe() after the page has fully loaded should still trigger
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// an initial intersection callback on the next rendering opportunity.
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window.addEventListener("load", () => {
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// Defer past the load event so any frame requested by the loading
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// pipeline has already been dispatched.
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setTimeout(() => {
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let observer = new IntersectionObserver(entries => {
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println(`isIntersecting=${entries[0].isIntersecting}`);
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done();
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});
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observer.observe(document.getElementById("target"));
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}, 100);
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});
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});
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</script>
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