Android EditText实现分割输入内容

当你想要在Android应用中实现分割输入内容的功能时，可以使用EditText控件来实现。下面是一个完整的攻略，包含了两个示例说明。

示例1：使用TextWatcher实现分割输入内容

首先，在你的布局文件中添加一个EditText控件：

<EditText
    android:id=\"@+id/editText\"
    android:layout_width=\"match_parent\"
    android:layout_height=\"wrap_content\"
    android:inputType=\"text\" />

然后，在你的Activity或Fragment中，添加以下代码：

EditText editText = findViewById(R.id.editText);
editText.addTextChangedListener(new TextWatcher() {
    private boolean isFormatting;
    private boolean deletingHyphen;
    private int hyphenStart;
    private boolean deletingBackward;

    @Override
    public void beforeTextChanged(CharSequence s, int start, int count, int after) {
        if (isFormatting)
            return;

        // Check if a hyphen is being deleted
        if (count == 1 && after == 0 && s.charAt(start) == '-') {
            deletingHyphen = true;
            hyphenStart = start;
            // Set the flag to true to prevent further formatting
            isFormatting = true;
        } else {
            deletingHyphen = false;
        }
    }

    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count) {
        if (isFormatting)
            return;

        // Check if a hyphen is being added
        if (count == 1 && before == 0 && s.charAt(start) == '-') {
            // Set the flag to true to prevent further formatting
            isFormatting = true;
            // Move the cursor to the right
            editText.setSelection(start + 1);
        } else if (count == 0 && before == 1 && deletingHyphen) {
            // Set the flag to true to prevent further formatting
            isFormatting = true;
            // Move the cursor to the left
            editText.setSelection(hyphenStart);
            deletingHyphen = false;
        }
    }

    @Override
    public void afterTextChanged(Editable s) {
        if (isFormatting) {
            isFormatting = false;
            return;
        }

        // Format the input by adding hyphens
        String input = s.toString().replaceAll(\"-\", \"\");
        StringBuilder formattedInput = new StringBuilder();
        int groupSize = 4;
        int totalGroups = (int) Math.ceil((double) input.length() / groupSize);
        for (int i = 0; i < totalGroups; i++) {
            int start = i * groupSize;
            int end = Math.min((i + 1) * groupSize, input.length());
            formattedInput.append(input, start, end);
            if (end != input.length()) {
                formattedInput.append(\"-\");
            }
        }

        // Set the formatted input back to the EditText
        int selection = editText.getSelectionEnd();
        editText.setText(formattedInput.toString());
        editText.setSelection(Math.min(selection, formattedInput.length()));
    }
});

这段代码使用了TextWatcher接口来监听EditText的文本变化。在beforeTextChanged()方法中，我们检查是否正在删除连字符。在onTextChanged()方法中，我们检查是否正在添加连字符，并根据需要移动光标。在afterTextChanged()方法中，我们格式化输入内容，将连字符添加到适当的位置。

示例2：使用InputFilter实现分割输入内容

另一种实现分割输入内容的方法是使用InputFilter。在你的Activity或Fragment中，添加以下代码：

EditText editText = findViewById(R.id.editText);
editText.setFilters(new InputFilter[] { new InputFilter.LengthFilter(19) });
editText.addTextChangedListener(new TextWatcher() {
    private boolean isFormatting;
    private boolean deletingHyphen;
    private int hyphenStart;
    private boolean deletingBackward;

    @Override
    public void beforeTextChanged(CharSequence s, int start, int count, int after) {
        if (isFormatting)
            return;

        // Check if a hyphen is being deleted
        if (count == 1 && after == 0 && s.charAt(start) == '-') {
            deletingHyphen = true;
            hyphenStart = start;
            // Set the flag to true to prevent further formatting
            isFormatting = true;
        } else {
            deletingHyphen = false;
        }
    }

    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count) {
        if (isFormatting)
            return;

        // Check if a hyphen is being added
        if (count == 1 && before == 0 && s.charAt(start) == '-') {
            // Set the flag to true to prevent further formatting
            isFormatting = true;
            // Move the cursor to the right
            editText.setSelection(start + 1);
        } else if (count == 0 && before == 1 && deletingHyphen) {
            // Set the flag to true to prevent further formatting
            isFormatting = true;
            // Move the cursor to the left
            editText.setSelection(hyphenStart);
            deletingHyphen = false;
        }
    }

    @Override
    public void afterTextChanged(Editable s) {
        if (isFormatting) {
            isFormatting = false;
            return;
        }

        // Format the input by adding hyphens
        String input = s.toString().replaceAll(\"-\", \"\");
        StringBuilder formattedInput = new StringBuilder();
        int groupSize = 4;
        int totalGroups = (int) Math.ceil((double) input.length() / groupSize);
        for (int i = 0; i < totalGroups; i++) {
            int start = i * groupSize;
            int end = Math.min((i + 1) * groupSize, input.length());
            formattedInput.append(input, start, end);
            if (end != input.length()) {
                formattedInput.append(\"-\");
            }
        }

        // Set the formatted input back to the EditText
        int selection = editText.getSelectionEnd();
        editText.removeTextChangedListener(this);
        editText.setText(formattedInput.toString());
        editText.setSelection(Math.min(selection, formattedInput.length()));
        editText.addTextChangedListener(this);
    }
});

这段代码使用了InputFilter.LengthFilter来限制输入的最大长度为19个字符。在afterTextChanged()方法中，我们格式化输入内容，将连字符添加到适当的位置。为了避免死循环，我们在设置EditText的文本时先移除TextWatcher，然后再添加回去。

以上就是实现分割输入内容的两个示例说明。你可以根据自己的需求选择其中一种方法来实现。希望对你有帮助！