Javafx:使用主题标签和号码实时更新电话号码文本字段

Question

目前正在开发一个文本字段，如果您输入号码，它会更新它，如下所示:

1##-####-####

12#-###-####

不幸的是，通过控制台将输入“1234”转换为“123-4##-####”是可行的，尽管当我推送更新的字符串“123-4##-####”时"它会自动将光标部分替换到开头，并不断替换第一个数字。有人可以帮忙在更新文本框中的字符串时保存光标位置吗？这是我的更新代码。

phoneField.textProperty().addListener((observable, oldValue, newValue) -> {
       Pattern p = Pattern.compile("-?\\d+");
       Matcher m = p.matcher(newValue);
       String result = "";
       String finalString = "";
       try {
           while (m.find()) {
               result = m.group();
           }
           int size = result.length();
           for(int i = 0; i < size; i++) {
               if(i == 3 || i == 6) finalString += "-";
               finalString += result.charAt(i);
           }
           for(int i = size; i < 10; i++) {
               if(i == 3 || i == 6) finalString += "-";
               finalString += "#";
           }
       } catch (Exception e) {
           finalString = "INVALID NUMBER";
       }
        phoneField.setText(finalString);
    });

Answer 1

您不应该使用监听器，因为您正在更改正在监听的属性，这意味着监听器会被调用两次。事实上，将会导致无限循环，除非 StringProperty 足够聪明，能够在新值等于旧值时避免触发更改。 (大多数 JavaBean 兼容类都以这种方式运行，但我不知道对这种行为有任何保证。)

为了限制 TextField 的行为，您通常需要使用 TextFormatter :

private TextField createPhoneField() {
    TextField phoneField = new TextField();
    phoneField.setPrefColumnCount(12);

    TextFormatter<String> formatter =
        new TextFormatter<>(this::addPhoneNumberMask);
    phoneField.setTextFormatter(formatter);

    return phoneField;
}

private TextFormatter.Change addPhoneNumberMask(
                                TextFormatter.Change change) {

    // Ignore cursor movements, unless the text is empty (in which case
    // we're initializing the field).
    if (!change.isContentChange() &&
        !change.getControlNewText().isEmpty()) {

        return change;
    }

    String text = change.getControlNewText();
    int start = change.getRangeStart();
    int end = change.getRangeEnd();

    int anchor = change.getAnchor();
    int caret = change.getCaretPosition();

    StringBuilder newText = new StringBuilder(text);

    int dash;
    while ((dash = newText.lastIndexOf("-")) >= start) {
        newText.deleteCharAt(dash);
        if (caret > dash) {
            caret--;
        }
        if (anchor > dash) {
            anchor--;
        }
    }

    while (newText.length() < 3) {
        newText.append('#');
    }
    if (newText.length() == 3 || newText.charAt(3) != '-') {
        newText.insert(3, '-');
        if (caret > 3 || (caret == 3 && end <= 3 && change.isDeleted())) {
            caret++;
        }
        if (anchor > 3 || (anchor == 3 && end <= 3 && change.isDeleted())) {
            anchor++;
        }
    }

    while (newText.length() < 7) {
        newText.append('#');
    }
    if (newText.length() == 7 || newText.charAt(7) != '-') {
        newText.insert(7, '-');
        if (caret > 7 || (caret == 7 && end <= 7 && change.isDeleted())) {
            caret++;
        }
        if (anchor > 7 || (anchor == 7 && end <= 7 && change.isDeleted())) {
            anchor++;
        }
    }

    while (newText.length() < 12) {
        newText.append('#');
    }

    if (newText.length() > 12) {
        newText.delete(12, newText.length());
    }

    text = newText.toString();
    anchor = Math.min(anchor, 12);
    caret = Math.min(caret, 12);

    change.setText(text);
    change.setRange(0, change.getControlText().length());
    change.setAnchor(anchor);
    change.setCaretPosition(caret);

    return change;
}