回答編集履歴
2
例追加
test
CHANGED
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@@ -19,3 +19,31 @@
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19
19
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```
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20
20
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21
21
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[https://www.w3.org/TR/cssom-view-1/#dom-document-elementfrompoint](https://www.w3.org/TR/cssom-view-1/#dom-document-elementfrompoint)
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22
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+
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23
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24
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25
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+
IntersectionObserver の例
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26
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27
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```jQuery
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28
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29
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const observer = new IntersectionObserver((entries, observer) => {
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30
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31
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const entry = entries.find(a => a.isIntersecting);
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32
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33
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if (entry) {
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34
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35
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const id = entry.target.id;
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36
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37
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$('nav li a[href="#' + id + '"]').closest('li').addClass('selected').siblings().removeClass('selected');
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38
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39
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}
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40
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41
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}, { rootMargin: '-50%' });
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42
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43
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$('section[id]').each((index, element) => observer.observe(element));
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44
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45
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```
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46
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47
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48
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49
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[https://developer.mozilla.org/ja/docs/Web/API/Intersection_Observer_API](https://developer.mozilla.org/ja/docs/Web/API/Intersection_Observer_API)
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1
不要個所削除
test
CHANGED
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@@ -19,7 +19,3 @@
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19
19
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```
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20
20
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21
21
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[https://www.w3.org/TR/cssom-view-1/#dom-document-elementfrompoint](https://www.w3.org/TR/cssom-view-1/#dom-document-elementfrompoint)
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22
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-
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23
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-
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24
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-
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25
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-
elementFromPoint
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