when a linkage event clicks on the second input box, you need to determine whether the previous box has entered a value. If a click event is triggered, there is no pop-up prompt to input the value of the previous input box
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now I click on the sequence to select the brand, and click on the model prompt to select the series first. I added focus events to this box of the series to determine whether the first box has a value. If there is a prompt, there is no prompt, but it will pop up all the time. How to deal with