切换分页之后，曲线会展示不出来

[litianji]

只需要点击“Next”，然后再点击“Previous”，曲线有时候就消失了；鼠标在上面移动能看见数据，只是没有曲线
Just click "Next" and then "Previous", and the curve sometimes disappears; moving the mouse over it shows the data, but there is no curve.
如下：

正确情况（Correct case）：