定制格式的Android文本输入框以接受信用卡号。

26

如何使EditText接受特定格式的输入

4digitnumber-4dignumber-4dignumber-4dignumber   

这段代码

text.addTextChangedListener(new TextWatcher() {
    int len = 0;
    String string ;
    @Override

    public void afterTextChanged(Editable s) {

        text.setOnKeyListener(new OnKeyListener()
        {   public boolean onKey(View v, int keyCode, KeyEvent event)
            {              
                    if (keyCode == KeyEvent.KEYCODE_DEL)
                    {

                    }
                    else{

                        string = text.getText().toString();
                        len = string.length()+1;
                        if(len%5==0){text.append("-");}

             }

                return false;      }   });
    }
});

添加时运行正常,但删除或编辑会导致问题。


https://dev59.com/F1HTa4cB1Zd3GeqPVNyk#37187857 - HenryChuang
https://dev59.com/Xofca4cB1Zd3GeqPj4bI 完美的解决方案 - karanatwal.github.io
8个回答

26

现在这对于软键盘/硬键盘的删除/编辑操作都可以正常工作。 感谢你的帮助。

package com.and;

import android.app.Activity;
import android.app.AlertDialog;
import android.inputmethodservice.KeyboardView;
import android.os.Bundle;
import android.telephony.PhoneNumberFormattingTextWatcher;
import android.text.Editable;
import android.text.Selection;
import android.text.Spannable;
import android.text.TextWatcher;
import android.text.format.Formatter;
import android.text.method.NumberKeyListener;
import android.view.KeyEvent;
import android.view.View;
import android.view.View.OnKeyListener;
import android.widget.EditText;
import android.widget.Toast;

public class ccformat extends Activity {

    String a;
    int keyDel;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        final EditText text = (EditText) findViewById(com.and.R.id.editText1);

        text.addTextChangedListener(new TextWatcher() {

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {

                boolean flag = true;
                String eachBlock[] = text.getText().toString().split("-");
                for (int i = 0; i < eachBlock.length; i++) {
                    if (eachBlock[i].length() > 4) {
                        flag = false;
                    }
                }
                if (flag) {

                    text.setOnKeyListener(new OnKeyListener() {

                        @Override
                        public boolean onKey(View v, int keyCode, KeyEvent event) {

                            if (keyCode == KeyEvent.KEYCODE_DEL)
                                keyDel = 1;
                            return false;
                        }
                    });

                    if (keyDel == 0) {

                        if (((text.getText().length() + 1) % 5) == 0) {

                            if (text.getText().toString().split("-").length <= 3) {
                                text.setText(text.getText() + "-");
                                text.setSelection(text.getText().length());
                            }
                        }
                        a = text.getText().toString();
                    } else {
                        a = text.getText().toString();
                        keyDel = 0;
                    }

                } else {
                    text.setText(a);
                }

            }

            @Override
            public void beforeTextChanged(CharSequence s, int start, int count,
                    int after) {
                // TODO Auto-generated method stub

            }

            @Override
            public void afterTextChanged(Editable s) {
            }
        });
    }
}

2
但是对于我的代码,当我按下返回键时,代码会崩溃...而且以上代码中的空格也无法删除。 - Taruni

21

这个正在运行:

public class EditTextSample extends Activity {
    // This regexp has to be improved, it does not detect case where you have
    // more than 4 digits in a middle group like: 1234-12345-123
    static final Pattern CODE_PATTERN = Pattern.compile("([0-9]{0,4})|([0-9]{4}-)+|([0-9]{4}-[0-9]{0,4})+");

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.edit_text_sample);

        final EditText editText = (EditText) findViewById(R.id.input);
        editText.addTextChangedListener(new TextWatcher() {

            @Override
            public void afterTextChanged(Editable s) {
                Log.w("", "input" + s.toString());

                if (s.length() > 0 && !CODE_PATTERN.matcher(s).matches()) {
                    String input = s.toString();
                    String numbersOnly = keepNumbersOnly(input);
                    String code = formatNumbersAsCode(numbersOnly);

                    Log.w("", "numbersOnly" + numbersOnly);
                    Log.w("", "code" + code);

                    editText.removeTextChangedListener(this);
                    editText.setText(code);
                    // You could also remember the previous position of the cursor
                    editText.setSelection(code.length());
                    editText.addTextChangedListener(this);
                }
            }

            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {
            }

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {
            }

            private String keepNumbersOnly(CharSequence s) {
                return s.toString().replaceAll("[^0-9]", ""); // Should of course be more robust
            }

            private String formatNumbersAsCode(CharSequence s) {
                int groupDigits = 0;
                String tmp = "";
                for (int i = 0; i < s.length(); ++i) {
                    tmp += s.charAt(i);
                    ++groupDigits;
                    if (groupDigits == 4) {
                        tmp += "-";
                        groupDigits = 0;
                    }
                }
                return tmp;
            }
        });
    }
}

不错的解决方案。虽然一种更低开销的锁定观察器并进行更改的方法是提供一个编辑布尔值。这就是Google在其TextWatcher实现中所做的方式。仍然要点赞。 - devunwired
1
的确,如果遵循谷歌的方法会更好,我没有想到:/ (请参见:http://grepcode.com/file/repository.grepcode.com/java/ext/com.google.android/android/2.1_r2/android/telephony/PhoneNumberFormattingTextWatcher.java) - Vincent Mimoun-Prat
请问在 Edit Text 控件中,有没有办法在每次编辑后将光标设置到特定位置,具体来说是文本末尾? - Rahul
editText.setSelection(code.length()); 这样做也可以。但是你可以在设置文本之前简单地记住位置,使用 editText.getSelectionStart()。 - Vincent Mimoun-Prat
这个解决方案会导致一种递归和堆栈溢出的情况。 - Cynichniy Bandera
显示剩余2条评论

7

如果你只是想在视觉上将数字进行分组,但不想改变EditText的值并添加破折号,可以使用这种Span方法:

EditText editText = findViewById(R.id.editText);
editText.addTextChangedListener(new TextWatcher() {
    @Override
    public void beforeTextChanged(CharSequence s, int start, int count, int after) {}

    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count) {}

    @Override
    public void afterTextChanged(Editable editable) {
        Object[] paddingSpans = editable.getSpans(0, editable.length(), DashSpan.class);
        for (Object span : paddingSpans) {
            editable.removeSpan(span);
        }

        addSpans(editable);
    }

    private static final int GROUP_SIZE = 4;

    private void addSpans(Editable editable) {

        final int length = editable.length();
        for (int i = 1; i * (GROUP_SIZE) < length; i++) {
            int index = i * GROUP_SIZE;
            editable.setSpan(new DashSpan(), index - 1, index,
                    Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
        }
    }
});

其中 DashSpan 类的代码如下:

/**
 * A {@link ReplacementSpan} used for spacing in {@link android.widget.EditText}
 * to space things out. Adds '-'s
 */
public class DashSpan extends ReplacementSpan {

    @Override
    public int getSize(@NonNull Paint paint, CharSequence text, int start, int end, FontMetricsInt fm) {
        float padding = paint.measureText("-", 0, 1);
        float textSize = paint.measureText(text, start, end);
        return (int) (padding + textSize);
    }

    @Override
    public void draw(@NonNull Canvas canvas, CharSequence text, int start, int end, float x, int top, int y,
                     int bottom, @NonNull Paint paint) {
        canvas.drawText(text.subSequence(start, end) + "-", x, y, paint);
    }
}

这样,您将通过破折号在视觉上进行分组,但getText()将返回没有任何分组的文本。
要强制仅输入数字,您可以将属性android:digits="0123456789"android:inputType="number"添加到EditText中。
此解决方案基于此库的代码。

3
在我的情况下,以下代码可以正常工作。
editTextCreditCard.addTextChangedListener(new FourDigitCardFormatWatcher());

为添加自定义类。

public class FourDigitCardFormatWatcher implements TextWatcher {

        private static final char space = ' ';

        @Override
        public void onTextChanged(CharSequence s, int start, int before, int count) {
        }

        @Override
        public void beforeTextChanged(CharSequence s, int start, int count, int after) {
        }

        @Override
        public void afterTextChanged(Editable s) {
            if (s.length() > 0 && (s.length() % 5) == 0) {
                final char c = s.charAt(s.length() - 1);
                if (space == c) {
                    s.delete(s.length() - 1, s.length());
                }
            }
            if (s.length() > 0 && (s.length() % 5) == 0) {
                char c = s.charAt(s.length() - 1);
                if (Character.isDigit(c) && TextUtils.split(s.toString(), String.valueOf(space)).length <= 3) {
                    s.insert(s.length() - 1, String.valueOf(space));
                }
            }
        }
    }

希望这能帮到您。

1
它适用于所有情况,当您插入或删除字符时,格式始终正确。请确保您设置了。
android:inputType="number"

/

myEditText.addTextChangedListener(new TextWatcher() {
        private final String space = "-"; // you can change this to whatever you want
        private final Pattern pattern = Pattern.compile("^(\\d{4}"+space+"{1}){0,3}\\d{1,4}$"); // check whether we need to modify or not
        @Override
        public void onTextChanged(CharSequence s, int st, int be, int count) {
            String currentText = myEditText.getText().toString();
            if (currentText.isEmpty() || pattern.matcher(currentText).matches())
                return; // no need to modify
            String numbersOnly = currentText.trim().replaceAll("[^\\d.]", "");; // remove everything but numbers
            String formatted = "";
            for(int i = 0; i < numbersOnly.length(); i += 4)
                if (i + 4 < numbersOnly.length())
                    formatted += numbersOnly.substring(i,i+4)+space;
                else
                    formatted += numbersOnly.substring(i);
            myEditText.setText(formatted);
            myEditText.setSelection(myEditText.getText().toString().length());
        }
        @Override
        public void beforeTextChanged(CharSequence s, int start, int count, int after) {}

        @Override
        public void afterTextChanged(Editable e) {}
});

做得很好,但不要在for循环中连接字符串,应该使用StringBuilder。formatted.append(numbersOnly.substring(i, i + 4)).append(space); - Ege Kuzubasioglu
找了两个小时,终于找到了,谢谢伙计!! - Vivek Thummar

0

如果你需要这个效果,你可以在EditText中使用code

enter image description here


0

在我看来,这里提供的答案似乎不能很好地处理删除、从中间删除等操作。以下是我的代码。它不限制输入的长度,但似乎可以处理各种插入和删除:

import android.text.Editable;
import android.text.TextWatcher;
import android.view.KeyEvent;
import android.view.View;
import android.widget.EditText;

public class HyphenDelimitTextWatcher implements TextWatcher {
    EditText mEditText;
    boolean mInside = false;
    boolean mWannaDeleteHyphen = false;
    boolean mKeyListenerSet = false;
    final static String MARKER = "|"; // filtered in layout not to be in the string

    @Override
    public void beforeTextChanged(CharSequence s, int start, int count, int after) {
        if(!mKeyListenerSet) {
            mEditText.setOnKeyListener(new View.OnKeyListener() {
                @Override
                public boolean onKey(View v, int keyCode, KeyEvent event) {
                    try {
                        mWannaDeleteHyphen = (keyCode == KeyEvent.KEYCODE_DEL
                                && mEditText.getSelectionEnd() - mEditText.getSelectionStart() <= 1
                                && mEditText.getSelectionStart() > 0
                                && mEditText.getText().toString().charAt(mEditText.getSelectionEnd() - 1) == '-');
                    } catch (IndexOutOfBoundsException e) {
                        // never to happen because of checks
                    }
                    return false;
                }
            });
            mKeyListenerSet = true;
        }
    }

    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count) {
        if (mInside) // to avoid recursive calls
            return;
        mInside = true;

        int currentPos = mEditText.getSelectionStart();
        String string = mEditText.getText().toString().toUpperCase();
        String newString = makePrettyString(string);

        mEditText.setText(newString);
        try {
            mEditText.setSelection(getCursorPos(string, newString, currentPos, mWannaDeleteHyphen));
        } catch (IndexOutOfBoundsException e) {
            mEditText.setSelection(mEditText.length()); // last resort never to happen
        }

        mWannaDeleteHyphen = false;
        mInside = false;
    }

    @Override
    public void afterTextChanged(Editable s) {
    }

    private String makePrettyString(String string) {
        String number = string.replaceAll("-", "");
        boolean isEndHyphen = string.endsWith("-") && (number.length()%4 == 0);
        return number.replaceAll("(.{4}(?!$))", "$1-") + (isEndHyphen ?"-":"");
    }

    private int getCursorPos(String oldString, String newString, int oldPos, boolean isDeleteHyphen) {
        int cursorPos = newString.length();
        if(oldPos != oldString.length()) {
            String stringWithMarker = oldString.substring(0, oldPos) + MARKER + oldString.substring(oldPos);

            cursorPos = (makePrettyString(stringWithMarker)).indexOf(MARKER);
            if(isDeleteHyphen)
                cursorPos -= 1;
        }
        return cursorPos;
    }

    public HyphenDelimitTextWatcher(EditText editText) {
        mEditText = editText;
    }
}

使用方法:

    mSomeEditText.addTextChangedListener(new HyphenDelimitTextWatcher(mSomeEditText));

0

这里是一个格式化正则表达式,用于以XXXX XXXX XXXX XXXX的格式显示卡片详细信息

etCreditCardNumber.addTextChangedListener(new TextWatcher() {
            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {

            }

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {
                etCreditCardNumber.setFloatingLabel(MaterialEditText.FLOATING_LABEL_HIGHLIGHT);

                String initial = s.toString();
                // remove all non-digits characters
                String processed = initial.replaceAll("\\D", "");

                // insert a space after all groups of 4 digits that are followed by another digit
                processed = processed.replaceAll("(\\d{4})(?=\\d)(?=\\d)(?=\\d)", "$1 ");

                //Remove the listener
                etCreditCardNumber.removeTextChangedListener(this);

                int index = etCreditCardNumber.getSelectionEnd();

                if (index == 5 || index == 10 || index == 15)
                    if (count > before)
                        index++;
                    else
                        index--;

                //Assign processed text
                etCreditCardNumber.setText(processed);

                try {
                    etCreditCardNumber.setSelection(index);
                } catch (Exception e) {
                    e.printStackTrace();
                    etCreditCardNumber.setSelection(s.length() - 1);
                }
                //Give back the listener
                etCreditCardNumber.addTextChangedListener(this);
            }

            @Override
            public void afterTextChanged(Editable s) {

            }
        });

你在发布前测试过这个吗? - Kishan Solanki
@KishanSolanki 是的,我曾在我的一个项目中使用它,并在此处粘贴了一份副本。我现在无法访问它,但它当时运行良好。 - Harpreet

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