【发布时间】：2012-08-01 04:05:28
【问题描述】：
如何让EditText接受格式输入：
4digit 4digit 4digit 4digit
我试过Custom format edit text input android to accept credit card number，但不幸的是我无法删除空格。只要有空间，我就不能删除它。请帮我找出问题。
【问题讨论】：
标签： android formatting android-edittext
【发布时间】：2012-08-01 04:05:28
【问题描述】：
找到多个“OK”的答案后。我转向了一个更好的 TextWatcher，它旨在独立于 TextView 正常工作。
TextWatcher 类如下：
/**
* Formats the watched EditText to a credit card number
*/
public static class FourDigitCardFormatWatcher implements TextWatcher {
// Change this to what you want... ' ', '-' etc..
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) {
// Remove spacing char
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());
}
}
// Insert char where needed.
if (s.length() > 0 && (s.length() % 5) == 0) {
char c = s.charAt(s.length() - 1);
// Only if its a digit where there should be a space we insert a space
if (Character.isDigit(c) && TextUtils.split(s.toString(), String.valueOf(space)).length <= 3) {
s.insert(s.length() - 1, String.valueOf(space));
}
}
}
}
然后将它添加到您的 TextView 中，就像您添加任何其他 TextWatcher 一样。
{
//...
mEditTextCreditCard.addTextChangedListener(new FourDigitCardFormatWatcher());
}
这将自动删除空间，这样用户在编辑时实际上可以减少击键次数。
警告
如果您使用inputType="numberDigit"，这将禁用“-”和“”字符，因此我建议使用inputType="phone"。这会启用其他字符，但只需使用自定义输入过滤器即可解决问题。
【讨论】：
-
我还想补充一点，您可以将 inputType 保留为数字并使用 android:digit="0123456789 _"。
-
@mpellegr 这适用于空格，但如果您使用破折号作为分隔符（显示在“数字”输入键盘上），用户可以输入它。一个简单的解决方法是删除 @ 987654328@ 在第一个 if 语句中。
-
这不支持中间字符串编辑...用户可以移动到字段中间添加/删除内容，并且间距将不正确。
-
刚刚花了 15 分钟尝试使用 android:digit="0123456789 _" （如@mpellegr 所述），没有运气，直到我看到这里 - stackoverflow.com/questions/3402693/… 它是“数字”而不是“数字”。也许它会帮助某人。
-
@Chris.Jenkins 如果我想从用户那里输入一个 19 位的数字怎么办，它不起作用。你能帮我吗
迟到的答案，但我想它可能对某人有帮助：
cardNumberEditText.addTextChangedListener(new TextWatcher() {
private static final int TOTAL_SYMBOLS = 19; // size of pattern 0000-0000-0000-0000
private static final int TOTAL_DIGITS = 16; // max numbers of digits in pattern: 0000 x 4
private static final int DIVIDER_MODULO = 5; // means divider position is every 5th symbol beginning with 1
private static final int DIVIDER_POSITION = DIVIDER_MODULO - 1; // means divider position is every 4th symbol beginning with 0
private static final char DIVIDER = '-';
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
// noop
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
// noop
}
@Override
public void afterTextChanged(Editable s) {
if (!isInputCorrect(s, TOTAL_SYMBOLS, DIVIDER_MODULO, DIVIDER)) {
s.replace(0, s.length(), buildCorrectString(getDigitArray(s, TOTAL_DIGITS), DIVIDER_POSITION, DIVIDER));
}
}
private boolean isInputCorrect(Editable s, int totalSymbols, int dividerModulo, char divider) {
boolean isCorrect = s.length() <= totalSymbols; // check size of entered string
for (int i = 0; i < s.length(); i++) { // check that every element is right
if (i > 0 && (i + 1) % dividerModulo == 0) {
isCorrect &= divider == s.charAt(i);
} else {
isCorrect &= Character.isDigit(s.charAt(i));
}
}
return isCorrect;
}
private String buildCorrectString(char[] digits, int dividerPosition, char divider) {
final StringBuilder formatted = new StringBuilder();
for (int i = 0; i < digits.length; i++) {
if (digits[i] != 0) {
formatted.append(digits[i]);
if ((i > 0) && (i < (digits.length - 1)) && (((i + 1) % dividerPosition) == 0)) {
formatted.append(divider);
}
}
}
return formatted.toString();
}
private char[] getDigitArray(final Editable s, final int size) {
char[] digits = new char[size];
int index = 0;
for (int i = 0; i < s.length() && index < size; i++) {
char current = s.charAt(i);
if (Character.isDigit(current)) {
digits[index] = current;
index++;
}
}
return digits;
}
});
这与开始字符串/结束字符串/中间字符串编辑完美配合，粘贴也完美工作。
【讨论】：
-
不能正常工作。如果输入数字，则将光标放回字段的开头并输入“12345”，它最终会变成“1234 65”
-
@IgorTyulkanov，我将您的代码添加到我的应用程序中，我只能在 EditText 中添加 4 个数字，我忘记了什么？
-
@piotrek1543，你能把你的代码贴在 gist e. G。我会试着检查一下
-
好的，我发现我的错误 - 糟糕
inputType:-) 解决并且工作正常，+1 -
太棒了！谢啦！还要检查
android:digits="0123456789 "是否包含 CARD_NUMBER_DIVIDER（注意末尾的空格），否则它会因堆栈溢出而崩溃！再次感谢！
我修改了 Chris Jenkins 的答案，使其更加健壮。这样，即使用户编辑了文本的中间，空格字符仍然会正确插入（并在错误的位置自动删除）。
要使这项工作正常进行，请确保EditText 属性设置如下（注意digits 上的空格）：
android:digits="01234 56789"
android:inputType="number"
android:maxLength="19"
那么这里就是您需要的TextWatcher。匿名类也可以设为静态，因为它独立于 EditText。
yourTextView.addTextChangedListener(new 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) {
// Remove all spacing char
int pos = 0;
while (true) {
if (pos >= s.length()) break;
if (space == s.charAt(pos) && (((pos + 1) % 5) != 0 || pos + 1 == s.length())) {
s.delete(pos, pos + 1);
} else {
pos++;
}
}
// Insert char where needed.
pos = 4;
while (true) {
if (pos >= s.length()) break;
final char c = s.charAt(pos);
// Only if its a digit where there should be a space we insert a space
if ("0123456789".indexOf(c) >= 0) {
s.insert(pos, "" + space);
}
pos += 5;
}
}
});
【讨论】：
-
工作正常。但是，它不允许删除最终位置之前的空格（它只是立即将空格放回去）。
-
同意@tom，但比其他解决方案好得多。
-
这个解决方案非常适合我，并且比其他解决方案更简单
这是一个使用正则表达式的更简洁的解决方案。尽管正则表达式可能效率不高，但在这种情况下它们就足够了，因为它处理最多 19 个字符的字符串，即使处理发生在每次按键之后。
editTxtCardNumber.addTextChangedListener(new TextWatcher() {
@Override
public void onTextChanged(CharSequence s, int arg1, int arg2,
int arg3) { }
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) { }
@Override
public void afterTextChanged(Editable s) {
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)", "$1 ");
// to avoid stackoverflow errors, check that the processed is different from what's already
// there before setting
if (!initial.equals(processed)) {
// set the value
s.replace(0, initial.length(), processed);
}
}
});
【讨论】：
-
你在最后一个分号之前缺少一个右括号
-
你晚上睡得怎么样！？合上括号！
-
应标记为最佳答案。只需很少的代码即可在所有用例中完美运行。
-
添加数字 9999，然后将光标移动到 EditText 的开头，然后添加数字 123456。结果是“1234 6599 99”而不是“1234 5699 99”。请注意，5 和 6 是相反的。
-
正如@TheIT 所说，从开始位置到插入仍然存在错误。因为我的解决方案很简单，而且效果很好。
这是我用于信用卡号的类。用法示例如下。
FormattedNumberEditText.kt
import android.content.Context
import android.text.Editable
import android.text.InputType
import android.text.TextWatcher
import android.text.method.DigitsKeyListener
import android.util.AttributeSet
import android.widget.EditText
open class FormattedNumberEditText : AppCompatEditText {
var prefix = ""
private set
var groupSeparator = ' '
private set
var numberOfGroups = 4
private set
var groupLength = 4
private set
var inputLength = numberOfGroups * (groupLength + 1) - 1
private set
private val digitsKeyListener = DigitsKeyListener.getInstance("0123456789")
private lateinit var separatorAndDigitsKeyListener: DigitsKeyListener
private var initCompleted = false
constructor(context: Context) : super(context) {
init(null)
}
constructor(context: Context, attrs: AttributeSet?) : super(context, attrs) {
init(attrs)
}
constructor(context: Context, attrs: AttributeSet?, defStyleAttr: Int) : super(context, attrs, defStyleAttr) {
init(attrs)
}
private fun init(attrs: AttributeSet?) {
if (attrs != null) {
val a = context.theme.obtainStyledAttributes(attrs, R.styleable.FormattedNumberEditText, 0, 0)
prefix = a.getString(R.styleable.FormattedNumberEditText_prefix) ?: prefix
val separatorStr = a.getString(R.styleable.FormattedNumberEditText_groupSeparator)
if (!separatorStr.isNullOrEmpty()) {
groupSeparator = separatorStr[0]
}
numberOfGroups = a.getInteger(R.styleable.FormattedNumberEditText_numberOfGroups, numberOfGroups)
groupLength = a.getInteger(R.styleable.FormattedNumberEditText_groupLength, groupLength)
}
inputLength = numberOfGroups * (groupLength + 1) - 1
separatorAndDigitsKeyListener = DigitsKeyListener.getInstance("0123456789$groupSeparator")
setText(prefix)
setSelection(text!!.length)
inputType = InputType.TYPE_CLASS_NUMBER
keyListener = digitsKeyListener
addTextChangedListener(TextChangeListener())
initCompleted = true
}
override fun onSelectionChanged(start: Int, end: Int) {
if (!initCompleted) {
return
}
// make sure input always starts with the prefix
if (!text!!.startsWith(prefix)) {
setText(prefix)
setSelection(text!!.length, text!!.length)
return
}
// make sure cursor is always at the end of the string
if (start != text!!.length || end != text!!.length) {
setSelection(text!!.length)
} else {
super.onSelectionChanged(start, end)
}
}
private inner class TextChangeListener : TextWatcher {
var textBefore = ""
var enteredText = ""
var deletedChars = 0
var listenerEnabled = true
override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) {
if (!listenerEnabled) return
textBefore = text.toString()
enteredText = ""
deletedChars = 0
}
override fun onTextChanged(text: CharSequence?, start: Int, lengthBefore: Int, lengthAfter: Int) {
if (!listenerEnabled) return
if (text == null) {
deletedChars = textBefore.length
return
}
if (text.length < textBefore.length) {
deletedChars = textBefore.length - text.length
return
}
enteredText = text.toString().substring(textBefore.length, text.length)
}
override fun afterTextChanged(s: Editable?) {
if (!listenerEnabled) return
if (s == null) {
return
}
listenerEnabled = false
if (deletedChars > 0) {
handleTextChange(s)
} else {
if (enteredText.length > 1) {
s.replace(s.length - enteredText.length, s.length, "")
// Append one char at a time
enteredText.forEach {
s.append("$it")
handleTextChange(s)
}
} else {
handleTextChange(s)
}
}
listenerEnabled = true
}
fun handleTextChange(s: Editable) {
if (s.length > inputLength) {
while (s.length > inputLength) {
s.delete(s.length - 1, s.length)
}
} else if (s.isNotEmpty() && s.length % (groupLength + 1) == 0) {
if (s.last() == groupSeparator) {
s.delete(s.length - 1, s.length)
} else if (s.last().isDigit() && s.length < inputLength) {
keyListener = separatorAndDigitsKeyListener
s.insert(s.length - 1, groupSeparator.toString())
keyListener = digitsKeyListener
}
}
}
}
}
attrs.xml（属于/res/values）
<?xml version="1.0" encoding="utf-8"?>
<resources>
<declare-styleable name="FormattedNumberEditText">
<attr name="prefix" format="string" />
<attr name="numberOfGroups" format="integer" />
<attr name="groupLength" format="integer" />
<attr name="groupSeparator" format="string" />
</declare-styleable>
</resources>
使用示例
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:padding="16dp">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Credit card number" />
<com.example.myapplication.FormattedNumberEditText
android:layout_width="match_parent"
android:layout_height="wrap_content" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
android:text="Credit card number (different separator)" />
<com.example.myapplication.FormattedNumberEditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:groupSeparator="-" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
android:text="Phone number starting with +370" />
<com.example.myapplication.FormattedNumberEditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:groupLength="13"
app:groupSeparator=" "
app:numberOfGroups="1"
app:prefix="+370\u0020" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
android:text="IBAN number starting with LT" />
<com.example.myapplication.FormattedNumberEditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:groupLength="4"
app:groupSeparator=" "
app:numberOfGroups="5"
app:prefix="LT" />
</LinearLayout>
【讨论】：
-
最佳答案，Kotlin 也是如此。谢谢@Egis
-
用于删除后面的空格 val ccNumber = cardNumber.replace("\\s".toRegex(), "")
我正在将我的解决方案添加到列表中。据我所知，它没有缺点。您可以在中间进行编辑，删除空格字符，复制粘贴等。
为了允许在字符串中的任何位置进行编辑并保持光标位置，遍历 Editable 并一一取出所有空格（如果有）。然后在适当的位置添加新的空格。这将确保光标随着对内容所做的更改而移动。
import java.util.LinkedList;
import android.text.Editable;
import android.text.TextWatcher;
import android.widget.EditText;
/**
* Formats the watched EditText to groups of characters, with spaces between them.
*/
public class GroupedInputFormatWatcher implements TextWatcher {
private static final char SPACE_CHAR = ' ';
private static final String SPACE_STRING = String.valueOf(SPACE_CHAR);
private static final int GROUPSIZE = 4;
/**
* Breakdown of this regexp:
* ^ - Start of the string
* (\\d{4}\\s)* - A group of four digits, followed by a whitespace, e.g. "1234 ". Zero or more times.
* \\d{0,4} - Up to four (optional) digits.
* (?<!\\s)$ - End of the string, but NOT with a whitespace just before it.
*
* Example of matching strings:
* - "2304 52"
* - "2304"
* - ""
*/
private final String regexp = "^(\\d{4}\\s)*\\d{0,4}(?<!\\s)$";
private boolean isUpdating = false;
private final EditText editText;
public GroupedInputFormatWatcher(EditText editText) {
this.editText = editText;
}
@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) {
String originalString = s.toString();
// Check if we are already updating, to avoid infinite loop.
// Also check if the string is already in a valid format.
if (isUpdating || originalString.matches(regexp)) {
return;
}
// Set flag to indicate that we are updating the Editable.
isUpdating = true;
// First all whitespaces must be removed. Find the index of all whitespace.
LinkedList<Integer> spaceIndices = new LinkedList <Integer>();
for (int index = originalString.indexOf(SPACE_CHAR); index >= 0; index = originalString.indexOf(SPACE_CHAR, index + 1)) {
spaceIndices.offerLast(index);
}
// Delete the whitespace, starting from the end of the string and working towards the beginning.
Integer spaceIndex = null;
while (!spaceIndices.isEmpty()) {
spaceIndex = spaceIndices.removeLast();
s.delete(spaceIndex, spaceIndex + 1);
}
// Loop through the string again and add whitespaces in the correct positions
for(int i = 0; ((i + 1) * GROUPSIZE + i) < s.length(); i++) {
s.insert((i + 1) * GROUPSIZE + i, SPACE_STRING);
}
// Finally check that the cursor is not placed before a whitespace.
// This will happen if, for example, the user deleted the digit '5' in
// the string: "1234 567".
// If it is, move it back one step; otherwise it will be impossible to delete
// further numbers.
int cursorPos = editText.getSelectionStart();
if (cursorPos > 0 && s.charAt(cursorPos - 1) == SPACE_CHAR) {
editText.setSelection(cursorPos - 1);
}
isUpdating = false;
}
}
【讨论】：
-
这种方法不允许自动删除非前导空格。添加文本 123456，将其转换为“1234 56”，现在将光标移动到 5 之前，即“1234 |56”，现在尝试删除空格。我希望数字 4 被删除，但光标却被移动了。
-
话虽如此，这是迄今为止我找到的最佳答案
不确定 TextWatcher 是否适合使用 - 我们应该使用 InputFilter
根据 Android 文档，TextWatcher 应该用于外部使用示例： 一个 [EditView] 用于密码输入+ 一个显示“弱”、“强”等的 [TextView] 视图...
对于信用卡格式，我使用的是InputFilter：
public class CreditCardInputFilter implements InputFilter {
public CharSequence filter(CharSequence source, int start, int end, Spanned dest, int dstart, int dend) {
if (dest != null & dest.toString().trim().length() > 24) return null;
if (source.length() == 1 && (dstart == 4 || dstart == 9 || dstart == 14))
return " " + new String(source.toString());
return null; // keep original
}
}
并结合长度过滤器（Android SDK）：
mEditCardNumber.setFilters(new InputFilter[]{
new InputFilter.LengthFilter(24),
new CreditCardInputFilter(),
});
这处理输入和删除数字时的情况。
(!) 但这不能处理复制/粘贴整个字符串的情况， 这应该在不同的 InputFilter 类中完成
希望对你有帮助！
【讨论】：
-
关心良好实践和高效工作的人！
-
我有你所拥有的，但正如你所提到的，我正在努力复制/粘贴整个字符串。由于我不得不增加额外空格的长度，现在用户可以复制/粘贴该长度的字符串，然后我该怎么办？将附加字符（分隔符）添加到值的整个想法对我来说似乎很可悲，因为在提取值进行验证时，您也必须删除这些分隔符。我希望在 Android 中有一种更简洁的方法来做到这一点。无论如何，你能指出我如何解决复制/粘贴问题的正确方向吗？是通过剪贴板管理器吗？
-
不适用于包含字符的文本（例如 IBAN）
-
我稍微改进了这个输入过滤器，支持复制/粘贴。 gist.github.com/Anrimian/168f3ed6b12df7d7da6230f418171dbd
-
这非常适合我想要做的事情。非常感谢！
我刚刚完成了下一个实现，对我来说效果很好，即使在 EditText 的任何位置粘贴和键入新文本。
/**
* Text watcher for giving "#### #### #### ####" format to edit text.
* Created by epool on 3/14/16.
*/
public class CreditCardFormattingTextWatcher implements TextWatcher {
private static final String EMPTY_STRING = "";
private static final String WHITE_SPACE = " ";
private String lastSource = EMPTY_STRING;
@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 s) {
String source = s.toString();
if (!lastSource.equals(source)) {
source = source.replace(WHITE_SPACE, EMPTY_STRING);
StringBuilder stringBuilder = new StringBuilder();
for (int i = 0; i < source.length(); i++) {
if (i > 0 && i % 4 == 0) {
stringBuilder.append(WHITE_SPACE);
}
stringBuilder.append(source.charAt(i));
}
lastSource = stringBuilder.toString();
s.replace(0, s.length(), lastSource);
}
}
}
用法： editText.addTextChangedListener(new CreditCardFormattingTextWatcher());
【讨论】：
-
嗨@epool！该代码运行良好（甚至删除了整个文本中间的一个字符）。谢谢你！但是，当我尝试使用不同的格式进行屏蔽时（出于其他目的，例如在位置 14 处插入字符“-”），光标在删除一个字符后，在其大小为 16 的字符串中返回两个位置。我的editText的maxLength是16，你知道怎么解决吗？
-
我不确定，我需要看看你的代码或者你到底想要做什么，也许你可以分享你的代码的 gits 链接。
-
我现在注意到，如果您的 EditText 的当前文本是 1234 5（使用您的方法）并且您需要删除字符“3”，例如，EditText 的光标会后退两个位置。如果您需要查看我的问题，我可以创建一个 Gist，但您可以看到这个问题发生在您自己的课程中。
-
这个问题你是对的，也许你可以用
int selectionStart = yourEditText.getSelectionStart(); int selectionEnd = yourEditText.getSelectionEnd(); yourEditText.setSelection(selectionStart, selectionEnd);来解决它。 -
我在这里试过，但它不起作用。如果你能解决它，我（可能还有其他人）会感激你。无论如何感谢@epool！
此实现可确保正确放置间距字符，即使用户编辑中间字符串也是如此。还支持出现在软键盘上的其他字符（如破折号）；也就是说，用户不能输入它们。可以进行的一项改进：此实现不允许删除字符串中间的空格字符。
public class CreditCardTextWatcher implements TextWatcher {
public static final char SPACING_CHAR = '-'; // Using a Unicode character seems to stuff the logic up.
@Override
public void beforeTextChanged(final CharSequence s, final int start, final int count, final int after) { }
@Override
public void onTextChanged(final CharSequence s, final int start, final int before, final int count) { }
@Override
public void afterTextChanged(final Editable s) {
if (s.length() > 0) {
// Any changes we make to s in here will cause this method to be run again. Thus we only make changes where they need to be made,
// otherwise we'll be in an infinite loop.
// Delete any spacing characters that are out of place.
for (int i=s.length()-1; i>=0; --i) {
if (s.charAt(i) == SPACING_CHAR // There is a spacing char at this position ,
&& (i+1 == s.length() // And it's either the last digit in the string (bad),
|| (i+1) % 5 != 0)) { // Or the position is not meant to contain a spacing char?
s.delete(i,i+1);
}
}
// Insert any spacing characters that are missing.
for (int i=14; i>=4; i-=5) {
if (i < s.length() && s.charAt(i) != SPACING_CHAR) {
s.insert(i, String.valueOf(SPACING_CHAR));
}
}
}
}
}
与适当的 PasswordTransformationMethod 实现配合使用以屏蔽 CC 数字。
【讨论】：
如果您使用的是 Kotlin，这可能会有所帮助：
class CreditCardTextFormatter(
private var separator: String = " - ",
private var divider: Int = 5
) : TextWatcher {
override fun afterTextChanged(s: Editable?) {
if (s == null) {
return
}
val oldString = s.toString()
val newString = getNewString(oldString)
if (newString != oldString) {
s.replace(0, oldString.length, getNewString(oldString))
}
}
private fun getNewString(value: String): String {
var newString = value.replace(separator, "")
var divider = this.divider
while (newString.length >= divider) {
newString = newString.substring(0, divider - 1) + this.separator + newString.substring(divider - 1)
divider += this.divider + separator.length - 1
}
return newString
}
override fun beforeTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {
}
override fun onTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {
}
}
XML：
<EditText
android:id="@+id/etCardNumber"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:digits="0123456789- "
android:inputType="number"
android:hint="____ - ____ - ____ - ____"
android:maxLength="25" />
以及如何使用它：
etCardNumber.addTextChangedListener(CreditCardTextFormatter())
【讨论】：
-
完美实现我的需求。
我认为无论是中间文本操作还是复制粘贴操作，我的解决方案都能很好地工作。
请看下面的代码，
class BankNumberTextWatcher implements TextWatcher {
private int previousCodeLen = 0;
@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 s) {
if (s.length() > 0) {
String numbersOnly = s.toString().replaceAll("[^0-9]", "");
// current code pattern miss-match, then handle cursor position and format the code
handleEditInput(numbersOnly);
} else {
previousCodeLen = 0;
}
}
/**
* Handle EditText input process for credit card including insert, delete during middle position,
* end position or copy-paste controller
*
* @param numbersOnly the pure number without non-digital characters
*/
private void handleEditInput(final String numbersOnly) {
String code = formatNumbersAsCode(numbersOnly);
int cursorStart = etBankCardNumber.getSelectionStart();
etBankCardNumber.removeTextChangedListener(this);
etBankCardNumber.setText(code);
int codeLen = code.length();
if (cursorStart != codeLen) {
// middle-string operation
if (cursorStart > 0 && cursorStart % 5 == 0) {
if (codeLen > previousCodeLen) {
// insert, move cursor to next
cursorStart++;
} else if (codeLen < previousCodeLen) {
// delete, move cursor to previous
cursorStart--;
}
}
etBankCardNumber.setSelection(cursorStart);
} else {
// end-string operation
etBankCardNumber.setSelection(codeLen);
}
etBankCardNumber.addTextChangedListener(this);
previousCodeLen = codeLen;
}
/**
* formats credit code like 1234 1234 5123 1234
*
* @param s
* @return
*/
public String formatNumbersAsCode(CharSequence s) {
if (TextUtils.isEmpty(s)) {
return "";
}
int len = s.length();
StringBuilder tmp = new StringBuilder();
for (int i = 0; i < len; ++i) {
tmp.append(s.charAt(i));
if ((i + 1) % 4 == 0 && (i + 1) != len) {
tmp.append(" ");
}
}
return tmp.toString();
}
}
将 inputType 设置为 EditText 的编号以避免布局文件中的其他字符。
希望对你有所帮助。
【讨论】：
请看这个project。 Android 表单编辑文本是 EditText 的扩展，为编辑文本带来了数据验证功能
【讨论】：
-
希望我早点知道，但我想知道为什么我现有的代码无法删除空格。
-
该项目看起来很有趣，但它似乎基本上是一个验证器，而不是一个输入格式化程序，这是 OP（和我）需要的。从任何屏幕截图中我都看不到它也可以输入格式。是吗？
经过大量搜索并没有得到任何满意的答案来满足我的需求，我最终编写了自己的函数。
以下是根据输入的卡类型格式化输入信用卡详细信息的示例。目前它处理 Visa、MasterCard 和 American Express 以进行格式化。
editTxtCardNumber.addTextChangedListener(new TextWatcher() {
private boolean spaceDeleted;
@Override
public void onTextChanged(CharSequence s, int arg1, int arg2,
int arg3) {
}
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
CharSequence charDeleted = s.subSequence(start, start + count);
spaceDeleted = " ".equals(charDeleted.toString());
}
@Override
public void afterTextChanged(Editable editable) {
if(editTxtCardNumber.getText().length() > 0 && editTxtCardNumber.getText().charAt(0) == '3') {
editTxtCardNumber.setFilters(new InputFilter[] { new InputFilter.LengthFilter(Constants.MAX_LENGTH_CARD_NUMBER_AMEX) });
editTxtCardNumber.removeTextChangedListener(this);
int cursorPosition = editTxtCardNumber.getSelectionStart();
String withSpaces = formatTextAmEx(editable);
editTxtCardNumber.setText(withSpaces);
editTxtCardNumber.setSelection(cursorPosition + (withSpaces.length() - editable.length()));
if (spaceDeleted) {
editTxtCardNumber.setSelection(editTxtCardNumber.getSelectionStart() - 1);
spaceDeleted = false;
}
editTxtCardNumber.addTextChangedListener(this);
} else if(editTxtCardNumber.getText().length() > 0
&& (editTxtCardNumber.getText().charAt(0) == '4' || editTxtCardNumber.getText().charAt(0) == '5')) {
editTxtCardNumber.setFilters(new InputFilter[] { new InputFilter.LengthFilter(Constants.MAX_LENGTH_CARD_NUMBER_VISA_MASTERCARD) });
editTxtCardNumber.removeTextChangedListener(this);
int cursorPosition = editTxtCardNumber.getSelectionStart();
String withSpaces = formatTextVisaMasterCard(editable);
editTxtCardNumber.setText(withSpaces);
editTxtCardNumber.setSelection(cursorPosition + (withSpaces.length() - editable.length()));
if (spaceDeleted) {
editTxtCardNumber.setSelection(editTxtCardNumber.getSelectionStart() - 1);
spaceDeleted = false;
}
editTxtCardNumber.addTextChangedListener(this);
} else {
editTxtCardNumber.setFilters(new InputFilter[] { new InputFilter.LengthFilter(Constants.MAX_LENGTH_CARD_NUMBER_VISA_MASTERCARD) });
editTxtCardNumber.removeTextChangedListener(this);
int cursorPosition = editTxtCardNumber.getSelectionStart();
String withSpaces = formatTextVisaMasterCard(editable);
editTxtCardNumber.setText(withSpaces);
editTxtCardNumber.setSelection(cursorPosition + (withSpaces.length() - editable.length()));
if (spaceDeleted) {
editTxtCardNumber.setSelection(editTxtCardNumber.getSelectionStart() - 1);
spaceDeleted = false;
}
editTxtCardNumber.addTextChangedListener(this);
}
}
});
private String formatTextVisaMasterCard(CharSequence text)
{
StringBuilder formatted = new StringBuilder();
int count = 0;
for (int i = 0; i < text.length(); ++i)
{
if (Character.isDigit(text.charAt(i)))
{
if (count % 4 == 0 && count > 0)
formatted.append(" ");
formatted.append(text.charAt(i));
++count;
}
}
return formatted.toString();
}
private String formatTextAmEx(CharSequence text)
{
StringBuilder formatted = new StringBuilder();
int count = 0;
for (int i = 0; i < text.length(); ++i)
{
if (Character.isDigit(text.charAt(i)))
{
if (count > 0 && ((count == 4) || (count == 10))) {
formatted.append(" ");
}
formatted.append(text.charAt(i));
++count;
}
}
return formatted.toString();
}
除了格式化空格外，我还应用了检查以确保卡号不超过其最大限制，并且当达到最大限制时，通过更改字体来通知用户他已输入所有数字。这是执行上述操作的函数。
public void checkCardNoEnteredCorrectly() {
if(editTxtCardNumber.getText().length() > 0 && editTxtCardNumber.getText().charAt(0) == '3') {
if(editTxtCardNumber.getText().length() == Constants.MAX_LENGTH_CARD_NUMBER_AMEX) {
editTxtCardNumber.setCompoundDrawablesWithIntrinsicBounds(getResources().getDrawable(R.drawable.amex), null, null, null);
} else {
editTxtCardNumber.setCompoundDrawablesWithIntrinsicBounds(getResources().getDrawable(R.drawable.amex), null, null, null);
}
} else if(editTxtCardNumber.getText().length() > 0 && editTxtCardNumber.getText().charAt(0) == '4') {
if(editTxtCardNumber.getText().length() == Constants.MAX_LENGTH_CARD_NUMBER_VISA_MASTERCARD) {
editTxtCardNumber.setCompoundDrawablesWithIntrinsicBounds(getResources().getDrawable(R.drawable.visa), null, null, null);
} else {
editTxtCardNumber.setCompoundDrawablesWithIntrinsicBounds(getResources().getDrawable(R.drawable.visa), null, null, null);
}
} else if(editTxtCardNumber.getText().length() > 0 && editTxtCardNumber.getText().charAt(0) == '5') {
if(editTxtCardNumber.getText().length() == Constants.MAX_LENGTH_CARD_NUMBER_VISA_MASTERCARD) {
editTxtCardNumber.setCompoundDrawablesWithIntrinsicBounds(getResources().getDrawable(R.drawable.master_card), null, null, null);
} else {
editTxtCardNumber.setCompoundDrawablesWithIntrinsicBounds(getResources().getDrawable(R.drawable.master_card), null, null, null);
}
} else {
editTxtCardNumber.setCompoundDrawablesWithIntrinsicBounds(getResources().getDrawable(R.drawable.credit_card_number), null, null, null);
}
}
注意：Constants.java中的声明如下：
public static final int MAX_LENGTH_CARD_NUMBER_VISA_MASTERCARD = 19;
public static final int MAX_LENGTH_CARD_NUMBER_AMEX = 17;
希望对你有帮助！
【讨论】：
您可能已经想通了，但这就是我所做的。我必须重写的唯一方法是 AfterTextChanged。
检查信用卡的形式是否已经有效，防止无限递归的基本情况
如果表单无效，请删除所有空格，然后复制到另一个字符串中，并在适当的地方插入空格。
然后简单地用你的新字符串替换可编辑的。
如果您需要特定步骤的代码，请随时询问。
Preethi，你不能删除空格的原因是你不能在 onTextChanged 回调中改变文本。来自开发者网站：
public abstract void onTextChanged (CharSequence s, int start, int before, int count) 在 API 级别 1 中添加
调用此方法是为了通知您，在 s 内，从 start 开始的 count 个字符刚刚替换了之前有 length 的旧文本。尝试通过此回调对 s 进行更改是错误的。
【讨论】：
int keyDel;
String a;
String a0;
int isAppent = 0;
final String ch = " ";
private void initListner() {
txtCreditNumber.addTextChangedListener(new TextWatcher() {
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
boolean flag = true;
if (s.length() > 19) {
txtCreditNumber.setText(a0);
txtCreditNumber.setSelection(txtCreditNumber.getText().length());
return;
}
String eachBlock[] = s.toString().split(ch);
for(int i = 0; i < eachBlock.length; i++) {
if (eachBlock[i].length() > 4) {
flag = false;
}
}
if (a0.length() > s.toString().length()) {
keyDel = 1;
}
if (flag) {
if (keyDel == 0) {
if (((txtCreditNumber.getText().length() + 1) % 5) == 0) {
if (s.toString().split(ch).length <= 3) {
isAppent = 1;
txtCreditNumber.setText(s + ch);
isAppent = 0;
txtCreditNumber.setSelection(txtCreditNumber.getText().length());
a = txtCreditNumber.getText().toString();
return;
}
}
if (isAppent == 0) {
String str = s.toString();
if (str.lastIndexOf(ch) == str.length() - 1) {
str = str.substring(0, str.lastIndexOf(ch));
keyDel = 1;
txtCreditNumber.setText(str);
keyDel = 0;
txtCreditNumber.setSelection(txtCreditNumber.getText().length());
a = txtCreditNumber.getText().toString();
return;
}
}
}
else {
String str = s.toString();
if (str.length() > 0 && str.lastIndexOf(ch) == str.length() - 1) {
str = str.substring(0, str.lastIndexOf(ch));
keyDel = 1;
txtCreditNumber.setText(str);
keyDel = 0;
txtCreditNumber.setSelection(txtCreditNumber.getText().length());
a = txtCreditNumber.getText().toString();
return;
}
else {
a = txtCreditNumber.getText().toString();
keyDel = 0;
}
}
}
else {
String str = s.toString();
str = str.substring(0, str.length() - 1) + ch + str.substring(str.length() - 1, str.length());
a = str;
txtCreditNumber.setText(a);
txtCreditNumber.setSelection(txtCreditNumber.getText().length());
}
}
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
// TODO Auto-generated method stub
a0 = s.toString();
}
@Override
public void afterTextChanged(Editable s) {
}
});
}
【讨论】：
这是一个适当地使用所有功能来做出决定的示例。 代码可能会更长一些，但它会更快，因为它主要使用给定值的函数（开始，之前，计数......）。 此示例在用户使用退格时每 4 位添加“-”，并删除它们。 同样，确保光标位于末尾。
public class TextWatcherImplement implements TextWatcher {
private EditText creditCard;
private String beforeText, currentText;
private boolean noAction, addStroke, dontAddChar, deleteStroke;
public TextWatcherImplement(EditText creditCard) {
// TODO Auto-generated constructor stub
this.creditCard = creditCard;
noAction = false;
addStroke = false;
dontAddChar = false;
deleteStroke = false;
}
/* here I save the previous string if the max character had achieved */
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
// TODO Auto-generated method stub
Log.i("TextWatcherImplement", "beforeTextChanged start==" + String.valueOf(start) + " count==" + String.valueOf(count) + " after==" + String.valueOf(after));
if (start >= 19)
beforeText = s.toString();
}
/* here I check were we add a character, or delete one.
if we add character and it is time to add a stroke, then I flag it -> addStroke
if we delete a character and it time to delete a stroke, I flag it -> deleteStroke
if we are in max character for the credit card, don't add char -> dontAddChar
*/
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
// TODO Auto-generated method stub
Log.i("TextWatcherImplement", "onTextChanged start==" + String.valueOf(start) + " before==" + String.valueOf(before) + " count==" + String.valueOf(count) + " noAction ==" + String.valueOf(noAction));
if ( (before < count) && !noAction ) {
if ( (start == 3) || (start == 8) || (start == 13) ) {
currentText = s.toString();
addStroke = true;
} else if (start >= 19) {
currentText = s.toString();
dontAddChar = true;
}
} else {
if ( (start == 4) || (start == 9) || (start == 14) ) { //(start == 5) || (start == 10) || (start == 15)
currentText = s.toString();
deleteStroke = true;
}
}
}
/* noAction flag is when we change the text, the interface is being called again.
the NoAction flag will prevent any action, and prevent a ongoing loop */
@Override
public void afterTextChanged(Editable stext) {
// TODO Auto-generated method stub
if (addStroke) {
Log.i("TextWatcherImplement", "afterTextChanged String == " + stext + " beforeText == " + beforeText + " currentText == " + currentText);
noAction = true;
addStroke = false;
creditCard.setText(currentText + "-");
} else if (dontAddChar) {
dontAddChar = false;
noAction = true;
creditCard.setText(beforeText);
} else if (deleteStroke) {
deleteStroke = false;
noAction = true;
currentText = currentText.substring(0, currentText.length() - 1);
creditCard.setText(currentText);
} else {
noAction = false;
creditCard.setSelection(creditCard.getText().length()); // set cursor at the end of the line.
}
}
}
【讨论】：
这是我的解决方案。我的 cmets 应该足以让 Android 开发人员了解正在发生的事情，但如果您有任何问题，请随时提问，我会尽我所能回答。
private KeyEvent keyEvent;
final TextWatcher cardNumberWatcher = new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence charSequence, int start, int before, int count) {
// NOT USING
}
@Override
public void onTextChanged(CharSequence charSequence, int start, int before, int count) {
// NOT USING
}
@Override
public void afterTextChanged(Editable editable) {
String cardNumbersOnly = editable.toString().replace("-", "");
/**
* @PARAM keyEvent
* This gets called upon deleting a character so you must keep a
* flag to ensures this gets skipped during character deletion
*/
if (cardNumbersOnly.length() >= 4 && keyEvent == null) {
formatCreditCardTextAndImage(this);
}
keyEvent = null;
}
};
cardNumberEditText.addTextChangedListener(cardNumberWatcher);
/**
* @LISTENER
* Must keep track of when the backspace event has been fired to ensure
* that the delimiter character and the character before it is deleted
* consecutively to avoid the user from having to press backspace twice
*/
cardNumberEditText.setOnKeyListener(new View.OnKeyListener() {
@Override
public boolean onKey(View v, int keyCode, KeyEvent event) {
if (event.getAction() != KeyEvent.ACTION_UP) {
// Hold reference of key event for checking within the text watcher
keyEvent = event;
String cardNumberString = cardNumberEditText.getText().toString();
if (keyCode == event.KEYCODE_DEL) {
if (cardNumberString.substring(cardNumberString.length() - 1).equals("-")) {
// Remove listener to avoid infinite looping
cardNumberEditText.removeTextChangedListener(cardNumberWatcher);
// Remove hyphen and character before it
cardNumberEditText.setText(cardNumberString.substring(0, cardNumberString.length() - 1));
// Set the cursor back to the end of the text
cardNumberEditText.setSelection(cardNumberEditText.getText().length());
// Add the listener back
cardNumberEditText.addTextChangedListener(cardNumberWatcher);
}
else if (cardNumberString.length() < 2) {
cardNumberBrandImageView.setImageDrawable(null);
cardNumberBrandImageView.setVisibility(View.INVISIBLE);
}
}
}
return false;
}
});
}
private void formatCreditCardTextAndImage (TextWatcher textWatcher) {
// Remove to avoid infinite looping
cardNumberEditText.removeTextChangedListener(textWatcher);
String cardNumberString = cardNumberEditText.getText().toString();
/**
* @CONDITION
* Append delimiter after every fourth character excluding the 16th
*/
if ((cardNumberString.length() + 1) % 5 == 0 && !cardNumberString.substring(cardNumberString.length() - 1).equals("-")) {
cardNumberEditText.setText(cardNumberString + "-");
}
// Set the cursor back to the end of the text
cardNumberEditText.setSelection(cardNumberEditText.getText().length());
cardNumberEditText.addTextChangedListener(textWatcher);
/**
* @CardBrand
* Is an enum utility class that checks the card numbers
* against regular expressions to determine the brand and updates the UI
*/
if (cardNumberString.length() == 2) {
switch (CardBrand.detect(cardNumberEditText.getText().toString())) {
case VISA:
cardNumberBrandImageView.setImageResource(R.drawable.visa);
cardNumberBrandImageView.setVisibility(View.VISIBLE);
card.setBrand(Brand.Visa);
break;
case MASTERCARD:
cardNumberBrandImageView.setImageResource(R.drawable.mastercard);
cardNumberBrandImageView.setVisibility(View.VISIBLE);
card.setBrand(Brand.MasterCard);
break;
case DISCOVER:
cardNumberBrandImageView.setImageResource(R.drawable.discover);
cardNumberBrandImageView.setVisibility(View.VISIBLE);
card.setBrand(Brand.Discover);
break;
case AMERICAN_EXPRESS:
cardNumberBrandImageView.setImageResource(R.drawable.americanexpress);
cardNumberBrandImageView.setVisibility(View.VISIBLE);
card.setBrand(Brand.AmericanExpress);
break;
case UNKNOWN:
cardNumberBrandImageView.setImageDrawable(null);
cardNumberBrandImageView.setVisibility(View.INVISIBLE);
card.setBrand(null);
break;
}
}
}
【讨论】：
这是一个使用TextWatcher 类的简单且易于定制的解决方案。可以使用addTextChangedListener() 方法将其分配给您的EditText。
new TextWatcher() {
/** Formats the Field to display user-friendly separation of the input values. */
@Override public final void afterTextChanged(final Editable pEditable) {
// Declare the separator.
final char lSeparator = '-';
// Declare the length of separated text. i.e. (XXXX-XXXX-XXXX)
final int lSeparationSize = 4;
// Declare the count; tracks the number of allowed characters in a row.
int lCount = 0;
// Iterate the Characters.
for(int i = 0; i < pEditable.length(); i++) {
// Fetch the current character.
final char c = pEditable.charAt(i);
// Is it a usual character. Here, we permit alphanumerics only.
final boolean lIsExpected = (Character.isDigit(c) || Character.isLetter(c)) && (c != lSeparator);
// Is the character expected?
if(lIsExpected) {
// Increase the count.
lCount++;
}
else {
// Is it a separator?
if(c == lSeparator) {
// Reset the count.
lCount = 0;
// Continue the iteration.
continue;
}
}
// Has the count been exceeded? Is there more text coming?
if(lCount >= (lSeparationSize + 1) && (i < pEditable.length())) {
// Reset the count.
lCount = 0;
// Insert the separator.
pEditable.insert(i, Character.toString(lSeparator));
// Increase the iteration count.
i++;
}
}
}
/** Unused overrides. */
@Override public final void beforeTextChanged(final CharSequence pCharSequence, final int pStart, final int pCount, final int pAfter) { }
@Override public final void onTextChanged(final CharSequence pCharSequence, final int pStart, final int pBefore, final int pCount) { }
}
或者，这里有一个基于epool's 实现的更简洁的实现。
public final class TextGroupFormattingListener implements TextWatcher {
/* Member Variables. */
private final int mGroupLength;
private final String mSeparator;
private String mSource;
/** Constructor. */
public TextGroupFormattingListener(final String pSeparator, final int pGroupLength) {
// Initialize Member Variables.
this.mSeparator = pSeparator;
this.mGroupLength = pGroupLength;
this.mSource = "";
}
/** Formats the Field to display user-friendly separation of the input values. */
@Override public final void afterTextChanged(final Editable pEditable) {
// Fetch the Source.
String lSource = pEditable.toString();
// Has the text changed?
if (!this.getSource().equals(lSource)) {
// Remove all of the existing Separators.
lSource = lSource.replace(this.getSeparator(), "");
// Allocate a StringBuilder.
StringBuilder lStringBuilder = new StringBuilder();
// Iterate across the Source String, which contains the raw user input.
for(int i = 0; i < lSource.length(); i++) {
// Have we exceeded the GroupLength?
if(i > 0 && i % this.getGroupLength() == 0) {
// Append the separator.
lStringBuilder.append(this.getSeparator());
}
// Append the user's character data.
lStringBuilder.append(lSource.charAt(i));
}
// Track changes to the Source.
this.setSource(lStringBuilder.toString());
// Replace the contents of the Editable with this new String.
pEditable.replace(0, pEditable.length(), this.getSource());
}
}
/** Unused overrides. */
@Override public final void beforeTextChanged(final CharSequence pCharSequence, final int pStart, final int pCount, final int pAfter) { }
@Override public final void onTextChanged(final CharSequence pCharSequence, final int pStart, final int pBefore, final int pCount) { }
public final int getGroupLength() {
return this.mGroupLength;
}
public final String getSeparator() {
return this.mSeparator;
}
private final void setSource(final String pSource) {
this.mSource = pSource;
}
private final String getSource() {
return this.mSource;
}
}
【讨论】：
以上答案都不适合我。我创建了一个解决 start-string/end-string/mid-string 问题的解决方案。复制和粘贴也应该可以正常工作。这支持万事达卡、维萨卡和美国运通卡。您可以更改分隔符。如果您不需要付款方式类型，只需将其删除。不过是 Kotlin。这个想法很简单。每次文本更改时，我都会删除所有分隔符并根据格式重新添加它们。解决了 start-string/mid-string 问题。那么唯一的问题是你需要在添加分隔符后计算出正确的文本位置。
fun addCreditCardNumberTxtWatcher(et: EditText, separator: Char, paymentMethodType: PaymentMethodType): TextWatcher {
val tw = object : TextWatcher {
var mBlock = false
override fun afterTextChanged(s: Editable) {
}
override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) {
Logger.d("_debug", "s: $s, start: $start, count: $count, after $after")
}
override fun onTextChanged(s: CharSequence?, start: Int, before: Int, count: Int) {
if (mBlock)
return
var lastPos = et.selectionStart
val oldStr = et.text.toString().replace(separator.toString(), "", false)
var newFormattedStr = ""
if (before > 0) {
if (lastPos > 0 && et.text.toString()[lastPos - 1] == separator) lastPos--
}
Logger.d("_debug", "lastPos: $lastPos, s: $s, start: $start, before: $before, count $count")
mBlock = true
oldStr.forEachIndexed { i, c ->
when (paymentMethodType) {
PaymentMethodType.MASTERCARD, PaymentMethodType.VISA -> {
if (i > 0 && i % 4 == 0) {
newFormattedStr += separator
}
}
PaymentMethodType.AMERICAN_EXPRESS -> {
if (i == 4 || i == 10 || i == 15) {
newFormattedStr += separator
}
}
}
newFormattedStr += c
}
et.setText(newFormattedStr)
if (before == 0) {
if (et.text.toString()[lastPos - 1] == separator) lastPos++
}
et.setSelection(lastPos)
mBlock = false
}
}
et.addTextChangedListener(tw)
return tw
}
【讨论】：
-
完美运行！不过，我建议不要使用可能会改变的付款方式类型（美国运通可能会采用不同的格式）。我建议使用必须存在分隔符的索引列表。例如，对于长度通常为 16 的卡片，分隔符将是
listOf(4, 9, 13)。对于长度通常为 15 的卡片，分隔符将是listOf(4, 10)
这个解决方案是为IBAN实现的，但原理是一样的，我试图纠正上面答案中的所有主要问题，如果你发现错误，请随时说出来，谢谢。
设置EditText并限制可以使用的字符：
private void setEditTextIBAN(View view) {
editTextIBAN = (EditText) view.findViewById(R.id.client_iban);
editTextIBAN.setKeyListener(
DigitsKeyListener.getInstance("ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890 "));
editTextIBAN.addTextChangedListener(new IBANTextWatcher());
}
这是 TextWatcher：
private class IBANTextWatcher implements TextWatcher {
// means divider position is every 5th symbol
private static final int DIVIDER_MODULO = 5;
private static final int GROUP_SIZE = DIVIDER_MODULO - 1;
private static final char DIVIDER = ' ';
private static final String STRING_DIVIDER = " ";
private String previousText = "";
private int deleteLength;
private int insertLength;
private int start;
private String regexIBAN = "(\\w{" + GROUP_SIZE + "}" + DIVIDER +
")*\\w{1," + GROUP_SIZE + "}";
private Pattern patternIBAN = Pattern.compile(regexIBAN);
@Override
public void beforeTextChanged(final CharSequence s, final int start, final int count, final int after) {
this.previousText = s.toString();
this.deleteLength = count;
this.insertLength = after;
this.start = start;
}
@Override
public void onTextChanged(final CharSequence s, final int start, final int before, final int count) {
}
@Override
public void afterTextChanged(final Editable s) {
String originalString = s.toString();
if (!previousText.equals(originalString) &&
!isInputCorrect(originalString)) {
String newString = previousText.substring(0, start);
int cursor = start;
if (deleteLength > 0 && s.length() > 0 &&
(previousText.charAt(start) == DIVIDER ||
start == s.length())) {
newString = previousText.substring(0, start - 1);
--cursor;
}
if (insertLength > 0) {
newString += originalString.substring(start, start + insertLength);
newString = buildCorrectInput(newString);
cursor = newString.length();
}
newString += previousText.substring(start + deleteLength);
s.replace(0, s.length(), buildCorrectInput(newString));
editTextIBAN.setSelection(cursor);
}
}
/**
* Check if String has the white spaces in the correct positions, meaning
* if we have the String "123456789" and there should exist a white space
* every 4 characters then the correct String should be "1234 5678 9".
*
* @param s String to be evaluated
* @return true if string s is written correctly
*/
private boolean isInputCorrect(String s) {
Matcher matcherDot = patternIBAN.matcher(s);
return matcherDot.matches();
}
/**
* Puts the white spaces in the correct positions,
* see the example in {@link IBANTextWatcher#isInputCorrect(String)}
* to understand the correct positions.
*
* @param s String to be corrected.
* @return String corrected.
*/
private String buildCorrectInput(String s) {
StringBuilder sbs = new StringBuilder(
s.replaceAll(STRING_DIVIDER, ""));
// Insert the divider in the correct positions
for (int i = GROUP_SIZE; i < sbs.length(); i += DIVIDER_MODULO) {
sbs.insert(i, DIVIDER);
}
return sbs.toString();
}
}
【讨论】：
如果有人还在寻找答案，
尝试使用 format-edit-text 库在一行代码中自动设置文本格式。这个库使用破折号来定义输入的格式。
editText.setFormat("any (dash) format");
如何使用
在 app/build.gradle 中添加 format-edit-text 库依赖
implementation 'com.androidwidgets:formatedittext:0.2.0'
在activity_main.xml中添加FormatEditText视图
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity"
android:focusableInTouchMode="true"
android:focusable="true">
<com.androidwidgets.formatedittext.widgets.FormatEditText
android:id="@+id/edit_text_1"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginStart="16dp"
android:layout_marginLeft="16dp"
android:layout_marginTop="16dp"
android:layout_marginEnd="16dp"
android:layout_marginRight="16dp"
android:imeOptions="actionSend"
android:inputType="number"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
在 MainActivity.java 中将信用卡格式设置为 FormatEditText 视图
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final FormatEditText editText1 = findViewById(R.id.edit_text_1);
editText1.setFormat("---- ---- ---- ----");
}
}
这将产生以下输出
PS：请确保将参数 inputType 添加到布局文件中的 FormatEditText 视图中。
android:inputType="number"
【讨论】：
我知道这个问题有点老了，但我需要为 IBAN 实施这个问题，并且对给定的答案不满意。所以我为此写了一些代码。但它以“模式”和“分隔符”为参数，因此也可以用于信用卡号。
这是扩展的文本观察器类。
import android.text.Editable;
import android.text.TextWatcher;
import android.widget.EditText;
public class IbanTextWatcher implements TextWatcher {
private int[] pattern;
private String divider;
private String before;
private EditText field;
private boolean dividerDeleted;
public IbanTextWatcher(int[] pattern, String divider, EditText field) {
this.divider = divider;
this.pattern = pattern;
this.field = field;
}
@Override
public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
before = charSequence.toString();
if (!String.valueOf(charSequence).equals("") && charSequence.length() > i) {
if (String.valueOf(before.charAt(i)).equals(getDivider())) {
dividerDeleted = true;
} else {
dividerDeleted = false;
}
}
}
@Override
public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
@Override
public void afterTextChanged(Editable editable) {
String input = editable.toString().replaceAll("\\s", "");
StringBuilder output = new StringBuilder();
boolean error = false;
int currentIndex = 0;
int cursorPosition = getField().getSelectionStart();
int lengthBefore;
int currentPatternMember = 0;
//prevent user to delete the divider
if (dividerDeleted && cursorPosition != getField().getText().length()) {
getField().setText(getBefore());
getField().setSelection(cursorPosition + 1);
return;
} else if (input.equals(getBefore().replaceAll("\\s", ""))) {
return;
}
for (int i = 0; i < getPattern().length; i++) {
error = false;
currentPatternMember = getPattern()[i];
try {
output.append(input.substring(currentIndex, currentIndex + currentPatternMember));
} catch (StringIndexOutOfBoundsException e) {
error = true;
}
if (!error) {
if (i != getPattern().length - 1) {
output.append(getDivider());
}
currentIndex += currentPatternMember;
} else {
break;
}
}
if (error) {
output.append(input.substring(currentIndex, input.length()));
}
cursorPosition = getField().getSelectionStart();
lengthBefore = getBefore().length();
getField().setText(output.toString());
if (cursorPosition != lengthBefore && cursorPosition != lengthBefore + 1) {
getField().setSelection(cursorPosition);
} else {
getField().setSelection(getField().getText().length());
}
}
public int[] getPattern() {
return pattern;
}
public String getDivider() {
return divider;
}
public String getBefore() {
return before;
}
public EditText getField() {
return field;
}
}
这就是我使用它的方式：
int[] pattern = {2,4,4,4,4,4,2}; //
iban.addTextChangedListener(new IbanTextWatcher(pattern, " ", iban)); //here iban is my edittext field
顺便说一下，我在xml中设置了字段的最大长度。
【讨论】：
-
很惊讶我找不到一个完善的库来处理 UI 中的 ibans ......这工作正常，但我可能会添加一些改进（显示字母大写，禁止特殊字符......）
-
在空格删除空格而不是最后一个输入后也删除。
在您的布局中：
<android.support.design.widget.TextInputEditText
android:id="@+id/et_credit_card_number"
android:digits=" 1234567890"
android:inputType="number"
android:maxLength="19"/>
这里是TextWachter，它在 16 位信用卡的每 4 位数字上设置一个空格。
class CreditCardFormatWatcher : TextWatcherAdapter() {
override fun afterTextChanged(s: Editable?) {
if (s == null || s.isEmpty()) return
s.forEachIndexed { index, c ->
val spaceIndex = index == 4 || index == 9 || index == 14
when {
!spaceIndex && !c.isDigit() -> s.delete(index, index + 1)
spaceIndex && !c.isWhitespace() -> s.insert(index, " ")
}
}
if (s.last().isWhitespace())
s.delete(s.length - 1, s.length)
}
}
【讨论】：
private class TextWatcherIBAN implements 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 s) {
textInputEditText.removeTextChangedListener(this);
formatIBANEditText(textInputEditText);
textInputEditText.addTextChangedListener(this);
}
}
public void formatIBANEditText(TextInputEditText editText) {
String decimalAmount = editText.getText().toString();
int selection = editText.getSelectionEnd() == decimalAmount.length() ? -1 : editText.getSelectionEnd();
decimalAmount = formatIBAN(decimalAmount);
editText.setText(decimalAmount);
if (selection != -1) {
editText.setSelection(selection);
} else {
editText.setSelection(decimalAmount.length());
}
}
public String formatIBAN(String text) {
return formatterIBAN(new StringBuilder(text));
}
private String formatterIBAN(StringBuilder text) {
int group = text.toString().length() / 5;
int spaceCount = getSpaceCount(text);
if (spaceCount < group) {
return formatterIBAN(text.insert(4 + 5 * spaceCount, space));
} else {
return text.toString();
}
}
private int getSpaceCount(StringBuilder text) {
int spaceCount = 0;
for (int index = 0; index < text.length(); index++) {
if (text.charAt(index) == space.charAt(0)) {
spaceCount++;
}
}
return spaceCount;
}
textInputEditText.addTextChangedListener(new TextWatcherIBAN());
【讨论】：
class XYZ : TextWatcher {
private val formatSymbols = DecimalFormatSymbols(Locale.getDefault())
private lateinit var formatter: DecimalFormat
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
.
.
formatSymbols.groupingSeparator = ' '
formatter = DecimalFormat("####,####", formatSymbols)
.
.
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
editText.addTextChangedListener(this)
}
override fun afterTextChanged(s: Editable?) {
if (editText.error != null) {
editText.error = null
}
editText.removeTextChangedListener(this)
try {
var originalString = s.toString()
if (originalString.contains(" ")) {
originalString = originalString.replace(" ", "", true)
}
val longVal: Long? = originalString.toLong()
val formattedString = formatter.format(longVal)
editText.setText(formattedString)
editText.setSelection(editText.text.length)
} catch (error: NumberFormatException) {
// Print Error Or Do Whatever you want.
}
editText.addTextChangedListener(this)
}
}
【讨论】：
这是我基于Igor Tyulkanov's idea的实现，它有一个小的改进，解决了光标位置问题
class CardNumbersInputWatcher(private val editText: EditText) : TextWatcher {
companion object {
private const val TOTAL_SYMBOLS = 19
private const val DIVIDER_DISTANCE = 4
private const val DIVIDER = ' '
}
override fun afterTextChanged(s: Editable) {
if (!isInputCorrect(s, TOTAL_SYMBOLS, DIVIDER_DISTANCE, DIVIDER)) {
val beforeCurPos = editText.selectionStart
val beforeLength = s.length
s.replace(0, s.length, buildCorrectString(s, TOTAL_SYMBOLS, DIVIDER_DISTANCE, DIVIDER))
if (beforeLength > TOTAL_SYMBOLS && beforeCurPos <= s.length && editText.selectionStart < beforeCurPos) {
editText.setSelection(beforeCurPos)
}
}
}
override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) = Unit
override fun onTextChanged(s: CharSequence?, start: Int, before: Int, count: Int) = Unit
}
private fun isInputCorrect(s: Editable, totalSymbols: Int, dividerDistance: Int, divider: Char): Boolean {
if (s.length > totalSymbols) {
return false
}
return s.withIndex().all { (index, c) ->
if (index != 0 && ((index + 1) % (dividerDistance + 1) == 0)) {
// it should be divider
c == divider
} else {
c.isDigit()
}
}
}
private fun buildCorrectString(s: Editable, totalSymbols: Int, dividerDistance: Int, divider: Char): String {
return buildString {
for (c in s) {
if (length >= totalSymbols) break
if (!c.isDigit()) continue
if (length > 0 && ((length + 1) % (dividerDistance + 1)) == 0) append(divider)
append(c)
}
}
}
【讨论】：
-
获取
java.lang.StackOverflowError: stack size 8192KB
1.复制并粘贴此类
class EditTextForCards @JvmOverloads constructor(
context: Context,
attrs: AttributeSet? = null,
defStyleAttr: Int = androidx.appcompat.R.attr.editTextStyle
) : AppCompatEditText(context, attrs, defStyleAttr) {
private var mCCPatterns = SparseArray<Pattern>()
private var mSeparator: Separator = Separator.NONE
private var mDrawableGravity: Gravity? = null/*Gravity.END*/
private var isValidCard: Boolean = false
private var mCurrentDrawableResId = Card.UNKNOWN.drawableRes
val textWithoutSeparator
get() = if (mSeparator == Separator.NONE) {
text.toString()
} else {
text.toString().replace(mSeparator.toRegex(), "")
}
val isCardValid: Boolean
get() = textWithoutSeparator.length > 12 && isValidCard
val cardType: Card
get() = Card.from(mCurrentDrawableResId)
enum class Separator(private val stringValue: String) {
NONE(""), SPACES(" "), DASHES("-");
override fun toString() = stringValue
internal fun toRegex() = stringValue.toRegex()
internal val length
get() = stringValue.length
}
enum class Gravity {
START, END, LEFT, RIGHT
}
enum class Card(internal val value: Int, @field:DrawableRes internal val drawableRes: Int) {
VISA(1, R.drawable.ic_visa),
MASTERCARD(2, R.drawable.ic_mastercard),
AMEX(4, R.drawable.amex),
DISCOVER(8, R.drawable.discover),
UNKNOWN(-1, R.drawable.ic_visa);
companion object {
internal fun from(@DrawableRes drawableRes: Int): Card {
for (card in values()) {
if (card.drawableRes == drawableRes) {
return card
}
}
return UNKNOWN
}
}
}
private val textWatcher = object : TextWatcher {
override fun afterTextChanged(s: Editable?) {}
override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) {}
override fun onTextChanged(
text: CharSequence,
start: Int,
lengthBefore: Int,
lengthAfter: Int
) {
val textWithoutSeparator = textWithoutSeparator
var mDrawableResId = 0
for (i in 0 until mCCPatterns.size()) {
val key = mCCPatterns.keyAt(i)
val p = mCCPatterns.get(key)
val m = p.matcher(textWithoutSeparator)
isValidCard = m.find()
if (isValidCard) {
mDrawableResId = key
break
}
}
// if (mDrawableResId != 0 && mDrawableResId != mCurrentDrawableResId) {
// mCurrentDrawableResId = mDrawableResId
// } else if (mDrawableResId == 0) {
// mCurrentDrawableResId = Card.UNKNOWN.drawableRes
// }
// addDrawable()
addSeparators()
}
}
init {
setDisabledCards()
inputType = InputType.TYPE_CLASS_PHONE
setSeparator(Separator.NONE)
// setDrawableGravity(Gravity.END)
attrs?.let { applyAttributes(it) }
addTextChangedListener(textWatcher)
}
private fun applyAttributes(attrs: AttributeSet) {
val a = context.theme.obtainStyledAttributes(
attrs,
R.styleable.EditTextForCards,
0, 0
)
try {
setSeparator(
Separator.values()[a.getInt(
R.styleable.EditTextForCards_separator,
Separator.NONE.ordinal
)]
)
setDisabledCardsInternal(a.getInt(R.styleable.EditTextForCards_disabledCards, 0))
setDrawableGravity(
Gravity.values()[a.getInt(
R.styleable.EditTextForCards_drawableGravity,
Gravity.END.ordinal
)]
)
} finally {
a.recycle()
}
}
private fun addDrawable() {
var currentDrawable = ContextCompat.getDrawable(context, mCurrentDrawableResId)
if (currentDrawable != null && error.isNullOrEmpty()) {
currentDrawable = resize(currentDrawable)
when (mDrawableGravity) {
Gravity.START -> setDrawablesRelative(start = currentDrawable)
Gravity.RIGHT -> setDrawables(right = currentDrawable)
Gravity.LEFT -> setDrawables(left = currentDrawable)
else -> setDrawablesRelative(end = currentDrawable)
}
}
}
private fun addSeparators() {
val text = text.toString()
if (mSeparator != Separator.NONE) {
if (text.length > 4 && !text.matches("(?:[0-9]{4}$mSeparator)+[0-9]{1,4}".toRegex())) {
val sp = StringBuilder()
val caretPosition = selectionEnd
val segments = splitString(text.replace(mSeparator.toRegex(), ""))
for (segment in segments) {
sp.append(segment).append(mSeparator)
}
setText("")
append(sp.delete(sp.length - mSeparator.length, sp.length).toString())
if (caretPosition < text.length)
setSelection(caretPosition)
}
}
}
private fun removeSeparators() {
var text = text.toString()
text = text.replace(" ".toRegex(), "").replace("-".toRegex(), "")
setText("")
append(text)
}
private fun splitString(s: String): Array<String?> {
val arrayLength = ceil(s.length / 4.toDouble()).toInt()
val result = arrayOfNulls<String>(arrayLength)
var j = 0
val lastIndex = result.size - 1
for (i in 0 until lastIndex) {
result[i] = s.substring(j, j + 4)
j += 4
}
result[lastIndex] = s.substring(j)
return result
}
/*@Deprecated("Please use the method that accepts a Separator enum instead.", ReplaceWith("this.setSeparator(Separator.)"))
fun setSeparator(@IntRange(from = 0, to = 2) separator: Int) {
require(!(separator > 2 || separator < 0)) {
"The separator has to be one of the following:" +
"NO_SEPARATOR." +
"SPACES_SEPARATOR." +
"DASHES_SEPARATOR."
}
setSeparator(Separator.values()[separator])
}*/
/**
* Use this method to set the separator style.
* The default separator is [Separator.NONE].
*
* @param separator the style of the separator.
*/
fun setSeparator(separator: Separator) {
mSeparator = separator
if (mSeparator != Separator.NONE) {
filters = arrayOf<InputFilter>(InputFilter.LengthFilter(23))
keyListener = DigitsKeyListener.getInstance("0123456789$mSeparator")
addSeparators()
} else {
filters = arrayOf<InputFilter>(InputFilter.LengthFilter(19))
keyListener = DigitsKeyListener.getInstance("0123456789")
removeSeparators()
}
}
/**
* Use this method to set the location of the card drawable.
* The default gravity is [Gravity.END].
*
* @param gravity the drawable location.
*/
fun setDrawableGravity(gravity: Gravity) {
mDrawableGravity = gravity
addDrawable()
}
private fun setDisabledCardsInternal(disabledCards: Int) {
val cards = ArrayList<Card>()
if (containsFlag(disabledCards, Card.VISA.value)) {
cards.add(Card.VISA)
}
if (containsFlag(disabledCards, Card.MASTERCARD.value)) {
cards.add(Card.MASTERCARD)
}
/*if (containsFlag(disabledCards, Card.AMEX.value)) {
cards.add(Card.AMEX)
}
if (containsFlag(disabledCards, Card.DISCOVER.value)) {
cards.add(Card.DISCOVER)
}*/
setDisabledCards(*cards.toTypedArray())
}
@Deprecated(
"Please use the method that accepts an array of Cards instead.",
ReplaceWith("this.setDisabledCards(cards)")
)
fun setDisabledCards(disabledCards: Int) {
setDisabledCardsInternal(disabledCards)
}
/**
* Use this method to set which cards are disabled.
* By default all supported cards are enabled.
*
* @param cards the cards to be disabled.
*/
fun setDisabledCards(vararg cards: Card) {
var disabledCards = 0
for (card in cards) {
disabledCards = disabledCards or card.value
}
mCCPatterns.clear()
if (!containsFlag(disabledCards, Card.VISA.value)) {
mCCPatterns.put(Card.VISA.drawableRes, Pattern.compile("^4[0-9]{1,12}(?:[0-9]{6})?$"))
}
if (!containsFlag(disabledCards, Card.MASTERCARD.value)) {
mCCPatterns.put(Card.MASTERCARD.drawableRes, Pattern.compile("^5[1-5][0-9]{0,14}$"))
}
/*if (!containsFlag(disabledCards, Card.AMEX.value)) {
mCCPatterns.put(Card.AMEX.drawableRes, Pattern.compile("^3[47][0-9]{0,13}$"))
}
if (!containsFlag(disabledCards, Card.DISCOVER.value)) {
mCCPatterns.put(Card.DISCOVER.drawableRes, Pattern.compile("^6(?:011|5[0-9]{1,2})[0-9]{0,12}$"))
}*/
textWatcher.onTextChanged("", 0, 0, 0)
}
private fun containsFlag(flagSet: Int, flag: Int): Boolean {
return flagSet or flag == flagSet
}
override fun onDraw(canvas: Canvas) {
super.onDraw(canvas)
var noDrawablesVisible = true
for (drawable in compoundDrawables) {
if (drawable != null) {
noDrawablesVisible = false
break
}
}
if (noDrawablesVisible) {
addDrawable()
}
}
private fun resize(image: Drawable) =
when (val height = measuredHeight - (paddingTop + paddingBottom)) {
in 1 until image.intrinsicHeight -> {
val bitmap = (image as BitmapDrawable).bitmap
val ratio = image.getIntrinsicWidth().toFloat() / image.intrinsicHeight.toFloat()
val resizedBitmap =
Bitmap.createScaledBitmap(bitmap, (height * ratio).toInt(), height, false)
resizedBitmap.density = Bitmap.DENSITY_NONE
BitmapDrawable(resources, resizedBitmap)
}
in Int.MIN_VALUE..0 -> null
else -> image
}
private fun setDrawablesRelative(
start: Drawable? = null,
top: Drawable? = null,
end: Drawable? = null,
bottom: Drawable? = null
) =
/*TextViewCompat.setCompoundDrawablesRelativeWithIntrinsicBounds(this, start, top, end, bottom)*/
TextViewCompat.setCompoundDrawablesRelativeWithIntrinsicBounds(this, null, null, null, null)
private fun setDrawables(
left: Drawable? = null,
top: Drawable? = null,
right: Drawable? = null,
bottom: Drawable? = null
) =
/*setCompoundDrawablesWithIntrinsicBounds(left, top, right, bottom)*/
setCompoundDrawablesWithIntrinsicBounds(null, null, null, null)
companion object {
@Deprecated("This constant has been replace with an enum.", ReplaceWith("Separator.NONE"))
const val NO_SEPARATOR = 0
@Deprecated("This constant has been replace with an enum.", ReplaceWith("Separator.SPACES"))
const val SPACES_SEPARATOR = 1
@Deprecated("This constant has been replace with an enum.", ReplaceWith("Separator.DASHES"))
const val DASHES_SEPARATOR = 2
@Deprecated("This constant has been replace with an enum.", ReplaceWith("null"))
const val NONE = 0
@Deprecated("This constant has been replace with an enum.", ReplaceWith("Card.VISA"))
const val VISA = 1
@Deprecated("This constant has been replace with an enum.", ReplaceWith("Card.MASTERCARD"))
const val MASTERCARD = 2
@Deprecated("This constant has been replace with an enum.", ReplaceWith("Card.AMEX"))
const val AMEX = 4
@Deprecated("This constant has been replace with an enum.", ReplaceWith("Card.DISCOVER"))
const val DISCOVER = 8
}
}
2。粘贴此样式
<declare-styleable name="EditTextForCards">
<attr name="separator" format="enum">
<enum name="no_separator" value="0" />
<enum name="spaces" value="1" />
<enum name="dashes" value="2" />
</attr>
<attr name="disabledCards">
<flag name="none" value="0" />
<flag name="visa" value="1" />
<flag name="mastercard" value="2" />
<flag name="amex" value="4" />
<flag name="discover" value="8" />
</attr>
<attr name="drawableGravity">
<enum name="start" value="0" />
<enum name="end" value="1" />
<enum name="left" value="2" />
<enum name="right" value="3" />
</attr>
</declare-styleable>
3.在您的布局文件中，通过
使用它<EditTextForCards
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="@dimen/dp_5"
android:digits="0123456789 "
android:hint="@string/card_number"
android:padding="@dimen/dp_20"
android:textColor="@android:color/white"
android:textColorHint="@android:color/white"
android:textSize="@dimen/sp_16"
app:separator="spaces" />
【讨论】：
import android.text.Editable;
import android.text.TextWatcher;
import android.widget.EditText;`
public class CreditCard implements TextWatcher
{
EditText editText;
public CreditCard(EditText editText)
{
this.editText = editText;
}
@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 s) {
try
{
editText.removeTextChangedListener(this);
String str = editText.getText().toString().replaceAll("-", "");
editText.setText(setDash(str));
editText.setSelection(editText.getText().toString().length());
editText.addTextChangedListener(this);
return;
}
catch (Exception ex)
{
ex.printStackTrace();
editText.addTextChangedListener(this);
}
}
public static String setDash(String value)
{
String str = "";
int j = 0;
for (int i = 0;i<value.length(); i++)
{
j++;
if (j == 5)
{
str = str+"-";
j = 1;
}
str = str + value.charAt(i);
}
return str;
}
public static String trimDashOfString(String string)
{
if (string.contains("-")) {
return string.replace("-", "");
} else {
return string;
}
}
}
【讨论】：