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ScrollView: refactor getScrollPosForColumn

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This commit is contained in:
Peter Fajdiga
2023-07-07 12:31:43 +02:00
parent 68d2c5bbd8
commit fa17b1fcc2
1 changed files with 22 additions and 11 deletions
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33
src/layout/ScrollView.ts
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@@ -34,21 +34,32 @@ class ScrollView {
// calculates ScrollPos that scrolls the column into view
public getScrollPosForColumn(column: Column) {
const left = this.gridToTilingSpace(column.getLeft());
const right = this.gridToTilingSpace(column.getRight());
let scrollPos: ScrollPos;
if (left < 0) {
scrollPos = this.getScrollPos(this.clampScrollX(this.scrollX + left));
} else if (right > this.tilingArea.width) {
scrollPos = this.getScrollPos(this.clampScrollX(this.scrollX + right - this.tilingArea.width));
const left = column.getLeft();
const right = column.getRight();
const initialScrollPos = this.getCurrentScrollPos();
let targetScrollX: number;
if (left < initialScrollPos.left) {
targetScrollX = this.clampScrollX(left);
} else if (right > initialScrollPos.right) {
targetScrollX = this.clampScrollX(right - this.tilingArea.width);
} else {
return this.getScrollPos(this.clampScrollX(this.scrollX));
}
const remainingSpace = this.tilingArea.width - this.grid.getVisibleColumnsWidth(scrollPos, true);
const overScrollX = Math.min(this.world.config.overscroll, Math.round(remainingSpace / 2));
const direction = left < 0 ? -1 : 1;
return this.getScrollPos(this.clampScrollX(scrollPos.left + overScrollX * direction));
const overscroll = this.getTargetOverscroll(targetScrollX, left < initialScrollPos.left);
return this.getScrollPos(this.clampScrollX(targetScrollX + overscroll));
}
private getTargetOverscroll(targetScrollX: number, scrollLeft: boolean) {
if (this.world.config.overscroll === 0) {
return 0;
}
const visibleColumnsWidth = this.grid.getVisibleColumnsWidth(this.getScrollPos(targetScrollX), true);
const remainingSpace = this.tilingArea.width - visibleColumnsWidth;
const overscrollX = Math.min(this.world.config.overscroll, Math.round(remainingSpace / 2));
const direction = scrollLeft ? -1 : 1;
return overscrollX * direction;
}
scrollToColumn(column: Column) {