限制用户在 JTextField 中输入时间的最佳方法 [英] Best way to constrain user to enter a time in a JTextField

问题描述

在我的一个 Java 应用程序中，有一个 字段，用户应该在其中输入时间.我知道，我可以简单地将它保留为普通的 JTextField 并且在验证时我可以检查值等等......

In one of my java applications, there is a field where the user is supposed to enter a time. I know, I can simply keep it as a normal JTextField and at the time of validation I can check the value and so on...

但我认为有比这更好的方法..

But I think there is a better way than that..

比如这是一个带日期的事情，那么JXDatePicker(swingx自带的)就可以很方便的使用了.最终，用户选择被保证是一个日期.

For example, if this is a matter with a date, then JXDatePicker (which comes with swingx) can be used very handily. Eventually, the users selection is guaranteed to be a date.

同样，也必须有更好的时间选择方法.如果您知道更好的解决方案，有人会分享您的知识吗?

Likewise, there must be a better way for time selection too. Will someone share your knowledge if you know a better solution.

任何想法都值得赞赏.谢谢！

Any thought is appreciated. Thank you!

推荐答案

you can use a JFormattedTextField 看看下面的例子，这将创建一个 JFormattedTextField将只接受数字并将它们放在 XXhXXminXXs 的形式中，然后将 ActionListener 添加到 JFormattedTextField 并尝试解析为有效的时间对象当 ENTER 现在我只展示了 JFormattedTextField 和 ActionListener 的使用我没有尝试转换或任何转换和解析为有效时间:

you could use a JFormattedTextField have a look at the example below, this will create a JFormattedTextField which will accept only numbers and put them in the form XXhXXminXXs then add a ActionListener to the JFormattedTextField and in that attempt to parse to a valid time object when ENTER for now I only show the use of the JFormattedTextField and the ActionListener I didn't attempt to convert or any converting and parsing for valid time:

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.text.ParseException;
import javax.swing.JFormattedTextField;
import javax.swing.JFrame;
import javax.swing.SwingUtilities;
import javax.swing.text.MaskFormatter;

public class FormattedTextFieldExample {

    public FormattedTextFieldExample() {
        initComponents();
    }

    private void initComponents() {
        JFrame frame = new JFrame("JFormattedTextField Example");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        MaskFormatter mask = null;
        try {
            mask = new MaskFormatter("##h##min##s");//the # is for numeric values
            mask.setPlaceholderCharacter('#');
        } catch (ParseException e) {
            e.printStackTrace();
        }

        //
        // Create a formatted text field that accept a valid time.
        //
        final JFormattedTextField timeField = new JFormattedTextField(mask);

        //Add ActionListener for when enter is pressed
        timeField.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent ae) {
                Object source = ae.getSource();
                if (source == timeField) {
                    //parse to a valid time here
                    System.out.println(timeField.getText());
                }
            }
        });

        frame.add(timeField);

        frame.pack();
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                new FormattedTextFieldExample();
            }
        });
    }
}

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