带有ActionListener和if语句的ComboBox

时间:2022-11-11 20:43:14

I'm trying to add an ActionListener to my ComboBox. I want to open a form when a item is selected from the box. I successfully implemented it on a JButton but I can't figure out how to do it in a combobox. Can someone please help me out?

我正在尝试将ActionListener添加到我的ComboBox中。我想从框中选择一个项目时打开一个表单。我在JButton上成功实现了它,但我无法弄清楚如何在组合框中实现它。有人可以帮帮我吗?

    JComboBox<String> valBox = new JComboBox<>();   

    valBox.addItem("Apparat");
    valBox.addItem("Smycke");
    valBox.addItem("Aktie");
    södra.add(valBox);

    valBox.addActionListener(new ActionListener() {
        public void actionPerformed(ActionEvent e) {
            if (valBox.getSelectedIndex() == 0)
                nyLyss.ApparatForm.form1();
        }
    });

The code that I wan't to execute when the first item is selected is this one:

选择第一个项目时我不想执行的代码是这个:

    class nyLyss implements ActionListener{
    public void actionPerformed(ActionEvent ae) {
        try{
            ApparatForm form1 = new ApparatForm();

            int svar = JOptionPane.showConfirmDialog(Layout.this, form1);
            if(svar != JOptionPane.OK_OPTION)
                return;
            String namn = form1.getNamn();
            int inköpspris = form1.getPris();
            int slitage = form1.getPris();
    //      saker ap = new saker(namn, inköpspris, slitage);
    //      alla.add(ap);

        }catch(NumberFormatException e){
            JOptionPane.showMessageDialog(Layout.this, "Felaktig indata!");
        }
    }
}

Thanks! :)

谢谢! :)

1 个解决方案

#1


0  

I would solve the problem with a ItemStateChanged listener on my combobox. Here a short example with a combobox called "mycombobox".

我会在我的组合框上用ItemStateChanged监听器解决问题。这是一个名为“mycombobox”的组合框的简短示例。

private void mycomboboxItemStateChanged(java.awt.event.ItemEvent evt) {                                            

    System.out.println(mycombobox.getSelectedItem());

} 

The result is, that the application is printing out the selected item after every change of the selected item in the combobox "mycombobox".

结果是,应用程序在组合框“mycombobox”中每次更改所选项目后打印出所选项目。

#1


0  

I would solve the problem with a ItemStateChanged listener on my combobox. Here a short example with a combobox called "mycombobox".

我会在我的组合框上用ItemStateChanged监听器解决问题。这是一个名为“mycombobox”的组合框的简短示例。

private void mycomboboxItemStateChanged(java.awt.event.ItemEvent evt) {                                            

    System.out.println(mycombobox.getSelectedItem());

} 

The result is, that the application is printing out the selected item after every change of the selected item in the combobox "mycombobox".

结果是,应用程序在组合框“mycombobox”中每次更改所选项目后打印出所选项目。