java - Change JComboBox selection on the basis of user confirmation

Question

Is there any way to keep user on old selected option from JComboBox. There is one confirmation I am asking to user when he/she wan't to change JComboBox's selected item, if user say yes, then only I want to keep new selection else set old item selected.

Is there any way to restrict JComboBox selection? I am using ItemListener and MouseListener to achieve above functionality.

Answer 1

ItemListener通常触发两个事件。第一个是一个DSESELECTED事件（旧值）和一个SELECTED事件（新值）。

您可以监控这些变化，并DESELECTED在它们发生时记录值

作为测试，你可以尝试这样的事情......

public void itemStateChanged(ItemEvent e) {
    if (e.getStateChange() == ItemEvent.SELECTED) {
        System.out.println("Selected :" + e.getItem());
    } else if (e.getStateChange() == ItemEvent.DESELECTED) {
        System.out.println("Deselected :" + e.getItem());
    }
}

如果用户对更改选择“否”，您可以恢复该DESELECTED值...