Add null checks for DOM queries in resizeLeftMask/resizeRightMask

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
This commit is contained in:
2026-03-09 21:06:17 +08:00
parent 68806aa29e
commit 242c96f978

View File

@@ -222,6 +222,7 @@ function resizeMask(chartInstance) {
function resizeLeftMask(chartInstance, from) {
const canvas = document.getElementById("chartCanvasId");
const mask = document.getElementById("chart-mask-left");
if (!canvas || !mask) return;
mask.style.left = `${canvas.offsetLeft + chartInstance.chartArea.left}px`;
mask.style.width = `${chartInstance.chartArea.width * from}px`;
mask.style.top = `${canvas.offsetTop + chartInstance.chartArea.top}px`;
@@ -235,6 +236,7 @@ function resizeLeftMask(chartInstance, from) {
function resizeRightMask(chartInstance, to) {
const canvas = document.getElementById("chartCanvasId");
const mask = document.getElementById("chart-mask-right");
if (!canvas || !mask) return;
mask.style.left = `${canvas.offsetLeft + chartInstance.chartArea.left + chartInstance.chartArea.width * to}px`;
mask.style.width = `${chartInstance.chartArea.width * (1 - to)}px`;
mask.style.top = `${canvas.offsetTop + chartInstance.chartArea.top}px`;