overscroll-behavior.js 2.5 KB

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  1. 'use strict';
  2. function _defaults(obj, defaults) { var keys = Object.getOwnPropertyNames(defaults); for (var i = 0; i < keys.length; i++) { var key = keys[i]; var value = Object.getOwnPropertyDescriptor(defaults, key); if (value && value.configurable && obj[key] === undefined) { Object.defineProperty(obj, key, value); } } return obj; }
  3. function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
  4. function _possibleConstructorReturn(self, call) { if (!self) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return call && (typeof call === "object" || typeof call === "function") ? call : self; }
  5. function _inherits(subClass, superClass) { if (typeof superClass !== "function" && superClass !== null) { throw new TypeError("Super expression must either be null or a function, not " + typeof superClass); } subClass.prototype = Object.create(superClass && superClass.prototype, { constructor: { value: subClass, enumerable: false, writable: true, configurable: true } }); if (superClass) Object.setPrototypeOf ? Object.setPrototypeOf(subClass, superClass) : _defaults(subClass, superClass); }
  6. var Declaration = require('../declaration');
  7. var OverscrollBehavior = function (_Declaration) {
  8. _inherits(OverscrollBehavior, _Declaration);
  9. function OverscrollBehavior() {
  10. _classCallCheck(this, OverscrollBehavior);
  11. return _possibleConstructorReturn(this, _Declaration.apply(this, arguments));
  12. }
  13. /**
  14. * Change property name for IE
  15. */
  16. OverscrollBehavior.prototype.prefixed = function prefixed(prop, prefix) {
  17. return prefix + 'scroll-chaining';
  18. };
  19. /**
  20. * Return property name by spec
  21. */
  22. OverscrollBehavior.prototype.normalize = function normalize() {
  23. return 'overscroll-behavior';
  24. };
  25. /**
  26. * Change value for IE
  27. */
  28. OverscrollBehavior.prototype.set = function set(decl, prefix) {
  29. if (decl.value === 'auto') {
  30. decl.value = 'chained';
  31. } else if (decl.value === 'none' || decl.value === 'contain') {
  32. decl.value = 'none';
  33. }
  34. return _Declaration.prototype.set.call(this, decl, prefix);
  35. };
  36. return OverscrollBehavior;
  37. }(Declaration);
  38. Object.defineProperty(OverscrollBehavior, 'names', {
  39. enumerable: true,
  40. writable: true,
  41. value: ['overscroll-behavior', 'scroll-chaining']
  42. });
  43. module.exports = OverscrollBehavior;