ba416d7e30945723637e3998b6b169cd166329a2fb90b4e78e3f714c81a392db65a05a32e691cfbf07b8ec5cc7c0866aa0e9160dd15800f4073f1c0a43142d 2.4 KB

12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364656667
  1. import createList from '../builders/build-list.mjs';
  2. import { isHorizontal } from '../utils.mjs';
  3. import { AUTO_ALIGNMENT, CENTERED_ALIGNMENT, END_ALIGNMENT, START_ALIGNMENT, SMART_ALIGNMENT } from '../defaults.mjs';
  4. const FixedSizeList = createList({
  5. name: "ElFixedSizeList",
  6. getItemOffset: ({ itemSize }, index) => index * itemSize,
  7. getItemSize: ({ itemSize }) => itemSize,
  8. getEstimatedTotalSize: ({ total, itemSize }) => itemSize * total,
  9. getOffset: ({ height, total, itemSize, layout, width }, index, alignment, scrollOffset) => {
  10. const size = isHorizontal(layout) ? width : height;
  11. const lastItemOffset = Math.max(0, total * itemSize - size);
  12. const maxOffset = Math.min(lastItemOffset, index * itemSize);
  13. const minOffset = Math.max(0, (index + 1) * itemSize - size);
  14. if (alignment === SMART_ALIGNMENT) {
  15. if (scrollOffset >= minOffset - size && scrollOffset <= maxOffset + size) {
  16. alignment = AUTO_ALIGNMENT;
  17. } else {
  18. alignment = CENTERED_ALIGNMENT;
  19. }
  20. }
  21. switch (alignment) {
  22. case START_ALIGNMENT: {
  23. return maxOffset;
  24. }
  25. case END_ALIGNMENT: {
  26. return minOffset;
  27. }
  28. case CENTERED_ALIGNMENT: {
  29. const middleOffset = Math.round(minOffset + (maxOffset - minOffset) / 2);
  30. if (middleOffset < Math.ceil(size / 2)) {
  31. return 0;
  32. } else if (middleOffset > lastItemOffset + Math.floor(size / 2)) {
  33. return lastItemOffset;
  34. } else {
  35. return middleOffset;
  36. }
  37. }
  38. case AUTO_ALIGNMENT:
  39. default: {
  40. if (scrollOffset >= minOffset && scrollOffset <= maxOffset) {
  41. return scrollOffset;
  42. } else if (scrollOffset < minOffset) {
  43. return minOffset;
  44. } else {
  45. return maxOffset;
  46. }
  47. }
  48. }
  49. },
  50. getStartIndexForOffset: ({ total, itemSize }, offset) => Math.max(0, Math.min(total - 1, Math.floor(offset / itemSize))),
  51. getStopIndexForStartIndex: ({ height, total, itemSize, layout, width }, startIndex, scrollOffset) => {
  52. const offset = startIndex * itemSize;
  53. const size = isHorizontal(layout) ? width : height;
  54. const numVisibleItems = Math.ceil((size + scrollOffset - offset) / itemSize);
  55. return Math.max(0, Math.min(total - 1, startIndex + numVisibleItems - 1));
  56. },
  57. initCache() {
  58. return void 0;
  59. },
  60. clearCache: true,
  61. validateProps() {
  62. }
  63. });
  64. export { FixedSizeList as default };
  65. //# sourceMappingURL=fixed-size-list.mjs.map