1) 如何在不使用插入符或焦点包裹到 invokeLater() 的情况下将 Cursor 设置为 0 位置(可以通过使用@camickr Formatted Text Field Tips 轻松解决)，有人知道另一种方法吗

2) How to reset Formatter 有时(通过键盘上的 TAB 提升焦点)，重置不起作用并且在 focusLost(空字段)Formatter 返回/重新生成的字符或字符串返回(最后知道在 setText(""); 之前，

Note: know code or following code is only this way，关于如何从 OTN 重置 Formatter，但是他们可怕的搜索规则....，只有代码(Jeanette 的问题或答案？？ ？)

import java.awt.event.*;
import java.beans.*;
import java.text.ParseException;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.text.Document;

public class FormattedNull {

    private JFormattedTextField field;
    private JButton focusButton;

    private JComponent createContent() {
        JComponent content = new JPanel();
        field = new JFormattedTextField(new Integer(55));
        field.setColumns(20);
        field.addPropertyChangeListener(getPropertyChangeListener());
        field.getDocument().addDocumentListener(getDocumentListener());
        content.add(field);
        focusButton = new JButton("just something focusable");
        focusButton.addActionListener(new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent e) {
                field.setValue(0);
                field.requestFocusInWindow();
            }
        });
        content.add(focusButton);
        return content;
    }

    protected void maybeCommitEdit(Document document) {
        try {
            field.commitEdit();
        } catch (ParseException e) {
            // uncomment to map empty string to null
            if (field.getText().length() == 0) {
                field.setValue(null);
            }
        }
    }

    /*public void commitEdit() throws ParseException {
    if(allowsNull() && isBlank()) {
    setValue(null);
    }
    else {
    super.commitEdit();
    }
    }*/
    private PropertyChangeListener getPropertyChangeListener() {
        PropertyChangeListener propertyChangeListener = new PropertyChangeListener() {

            @Override
            public void propertyChange(PropertyChangeEvent evt) {
                if ("value".equals(evt.getPropertyName())) {
                    matchValueChanged(evt.getNewValue());
                }
            }
        };
        return propertyChangeListener;
    }

    protected void matchValueChanged(Object value) {
        System.out.println("got new value: " + value);
    }

    private DocumentListener getDocumentListener() {
        DocumentListener documentListener = new DocumentListener() {

            @Override
            public void removeUpdate(DocumentEvent e) {
                maybeCommitEdit(e.getDocument());
            }

            @Override
            public void insertUpdate(DocumentEvent e) {
                maybeCommitEdit(e.getDocument());
            }

            @Override
            public void changedUpdate(DocumentEvent e) {
            }
        };
        return documentListener;
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {

            @Override
            public void run() {
                JFrame frame = new JFrame("");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.add(new FormattedNull().createContent());
                frame.setLocationRelativeTo(null);
                frame.pack();
                frame.setVisible(true);
            }
        });
    }
}

附件图片基于我的sscce

import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import javax.swing.*;
import javax.swing.text.MaskFormatter;

public class TestTest {

    private JFormattedTextField myFormattedField1 = new JFormattedTextField(createFormatter("AAAAAAAAAAAA"));
    private JFormattedTextField myFormattedField2 = new JFormattedTextField(createFormatter("AAAAAAAAAAAA"));
    private JFormattedTextField myFormattedField3 = new JFormattedTextField(createFormatter("AAAAAAAAAAAA"));
    private JFormattedTextField myFormattedField4 = new JFormattedTextField(createFormatter("AAAAAAAAAAAA"));
    private JButton jb = new JButton("Reset to Default");
    private JFrame frame = new JFrame("Text Test");

    public TestTest() {
        myFormattedField1.setText("ABCDEFGHIJKL");
        myFormattedField2.setText("ABCDEFGHIJKL");
        myFormattedField3.setText("ABCDEFGHIJKL");
        myFormattedField4.setText("ABCDEFGHIJKL");

        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setLocation(150, 150);
        frame.setLayout(new GridLayout(5, 0));
        frame.add(jb);
        frame.add(myFormattedField1);
        frame.add(myFormattedField2);
        frame.add(myFormattedField3);
        frame.add(myFormattedField4);
        jb.addActionListener(new java.awt.event.ActionListener() {

            @Override
            public void actionPerformed(ActionEvent e) {
                myFormattedField1.setText("");
                myFormattedField2.setText("");
                myFormattedField3.setText("");
                myFormattedField4.setText("");
            }
        });
        frame.pack();
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        TestTest textTest = new TestTest();
    }

    protected MaskFormatter createFormatter(String s) {
        MaskFormatter formatter = null;
        try {
            formatter = new MaskFormatter(s);
        } catch (java.text.ParseException exc) {
            System.err.println("formatter is bad: " + exc.getMessage());
        }
        return formatter;
    }
}

最佳答案

1. 在 Mac OS 上，UI 委托(delegate)的默认行为 com.apple.laf.AquaTextFieldF 类似于 CaretPositionListener:

   • Tab 或 Shift-Tab:将插入符放在字段的开头。

   • 单击:将插入符号短暂放置在字段的开头，然后将其移动到单击点。

   IMO，CaretPositionListener 可以更顺利地完成后者。

2. JFormattedTextField 失去焦点时的默认行为是 COMMIT_OR_REVERT。在下面的示例中，Tab 通过第一个无效字段来查看效果。格式化程序既不能提交也不能还原为无效值，因此它替换了 MASK.length() 空格。这个值是有效的，尽管有点模糊。

附录:我更新了下面的代码以允许更改 setFocusLostBehavior() 。

代码:

import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
import javax.swing.text.MaskFormatter;

/** @see http://stackoverflow.com/questions/7378821 */
public class TrashTest {

    private static final String MASK = "########";
    private static final String DEFAULT = "01234567";
    private static final String BOGUS = "0123456";
    private JFormattedTextField jtf1 = createField();
    private JFormattedTextField jtf2 = createField();
    private JFormattedTextField jtf3 = createField();
    private JFormattedTextField jtf4 = createField();
    private JButton reset = new JButton("Reset to Default");
    private JComboBox combo = new JComboBox();
    private JFrame frame = new JFrame("Text Test");

    public TrashTest() {
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setLocation(150, 150);
        frame.setLayout(new GridLayout(0, 1));
        frame.add(reset);
        frame.add(jtf1);
        frame.add(jtf2);
        frame.add(jtf3);
        frame.add(jtf4);
        frame.add(combo);
        this.initFields();
        reset.addActionListener(new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent e) {
                initFields();
            }
        });
        for (Edit e : Edit.values()) {
            combo.addItem(e);
        }
        combo.setSelectedIndex(jtf1.getFocusLostBehavior());
        combo.addActionListener(new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent e) {
                Edit current = (Edit) combo.getSelectedItem();
                jtf1.setFocusLostBehavior(current.value);
            }
        });
        frame.pack();
        frame.setVisible(true);
    }

    private void initFields() {
        jtf1.setText(BOGUS);
        jtf2.setText(DEFAULT);
        jtf3.setText(DEFAULT);
        jtf4.setText(DEFAULT);
    }

    protected JFormattedTextField createField() {
        MaskFormatter formatter = null;
        try {
            formatter = new MaskFormatter(MASK);
        } catch (java.text.ParseException e) {
            e.printStackTrace(System.out);
        }
        JFormattedTextField jtf = new JFormattedTextField(formatter);
        return jtf;
    }

    enum Edit {

        COMMIT(JFormattedTextField.COMMIT),
        COMMIT_OR_REVERT(JFormattedTextField.COMMIT_OR_REVERT),
        REVERT(JFormattedTextField.REVERT),
        PERSIST(JFormattedTextField.PERSIST);
        private int value;

        private Edit(int n) {
            this.value = n;
        }

        public static Edit getEnum(int n) {
            for (Edit e : Edit.values()) {
                if (e.value == n) {
                    return e;
                }
            }
            return Edit.COMMIT_OR_REVERT;
        }
    }

    public static void main(String[] args) {
        TrashTest textTest = new TrashTest();
    }
}

关于java - JFormattedTextField 问题，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/7378821/