| <!DOCTYPE html> |
| <meta name="viewport" content="width=device-width,initial-scale=1"> |
| <script src="/resources/testharness.js"></script> |
| <script src="/resources/testharnessreport.js"></script> |
| <script src="./resources/intersection-observer-test-utils.js"></script> |
| |
| <style> |
| pre, #log { |
| position: absolute; |
| top: 0; |
| left: 200px; |
| } |
| .spacer { |
| height: calc(100vh + 100px); |
| } |
| #root { |
| display: inline-block; |
| overflow-y: scroll; |
| height: 240px; |
| border: 3px solid black; |
| } |
| #target { |
| width: 100px; |
| height: 100px; |
| margin: 200px 0 0 0; |
| background-color: green; |
| } |
| </style> |
| |
| <div id="root"> |
| <div id="target"></div> |
| </div> |
| |
| <script> |
| var entries = []; |
| var root, target; |
| |
| runTestCycle(function() { |
| target = document.getElementById("target"); |
| assert_true(!!target, "target exists"); |
| root = document.getElementById("root"); |
| assert_true(!!root, "root exists"); |
| var observer = new IntersectionObserver(function(changes) { |
| entries = entries.concat(changes) |
| }, { root: root, threshold: [0.5] }); |
| observer.observe(target); |
| entries = entries.concat(observer.takeRecords()); |
| assert_equals(entries.length, 0, "No initial notifications."); |
| runTestCycle(step0, "First rAF"); |
| }, "First observation with a threshold."); |
| |
| function step0() { |
| root.scrollTop = 20; |
| runTestCycle(step1, "root.scrollTop = 20"); |
| checkLastEntry(entries, 0, [ 11, 111, 211, 311, 11, 111, 211, 251, 11, 111, 11, 251, false]); |
| } |
| |
| function step1() { |
| checkLastEntry(entries, 1, [ 11, 111, 191, 291, 11, 111, 191, 251, 11, 111, 11, 251, true]); |
| } |
| </script> |
