我有一个EditText，其中用户应输入一个包含小数的数字，我想要一个千位分隔符自动添加到输入数字上我尝试了几个其他方法但有些不允许浮点数，所以我想出了这个代码只适用于字符串输入没有实时编辑到可能有千位分隔符的代码，并且错误似乎源于s.replace（）;
am2 = new TextWatcher(){
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
public void onTextChanged(CharSequence s, int start, int before, int count) {}
public void afterTextChanged(Editable s) {
if (s.toString().equals("")) {
amount.setText("");
value = 0;
}else{
StringBuffer strBuff = new StringBuffer();
char c;
for (int i = 0; i < amount2.getText().toString().length() ; i++) {
c = amount2.getText().toString().charAt(i);
if (Character.isDigit(c)) {
strBuff.append(c);
}
}
value = Double.parseDouble(strBuff.toString());
reverse();
NumberFormat nf2 = NumberFormat.getInstance(Locale.ENGLISH);
((DecimalFormat)nf2).applyPattern("###,###.#######");
s.replace(0, s.length(), nf2.format(value));
}
}
};
答案 0 :(得分：33)
此类解决了问题，允许十进制输入并添加千位分隔符。
public class NumberTextWatcher implements TextWatcher {
private DecimalFormat df;
private DecimalFormat dfnd;
private boolean hasFractionalPart;
private EditText et;
public NumberTextWatcher(EditText et)
{
df = new DecimalFormat("#,###.##");
df.setDecimalSeparatorAlwaysShown(true);
dfnd = new DecimalFormat("#,###");
this.et = et;
hasFractionalPart = false;
}
@SuppressWarnings("unused")
private static final String TAG = "NumberTextWatcher";
public void afterTextChanged(Editable s)
{
et.removeTextChangedListener(this);
try {
int inilen, endlen;
inilen = et.getText().length();
String v = s.toString().replace(String.valueOf(df.getDecimalFormatSymbols().getGroupingSeparator()), "");
Number n = df.parse(v);
int cp = et.getSelectionStart();
if (hasFractionalPart) {
et.setText(df.format(n));
} else {
et.setText(dfnd.format(n));
}
endlen = et.getText().length();
int sel = (cp + (endlen - inilen));
if (sel > 0 && sel <= et.getText().length()) {
et.setSelection(sel);
} else {
// place cursor at the end?
et.setSelection(et.getText().length() - 1);
}
} catch (NumberFormatException nfe) {
// do nothing?
} catch (ParseException e) {
// do nothing?
}
et.addTextChangedListener(this);
}
public void beforeTextChanged(CharSequence s, int start, int count, int after)
{
}
public void onTextChanged(CharSequence s, int start, int before, int count)
{
if (s.toString().contains(String.valueOf(df.getDecimalFormatSymbols().getDecimalSeparator())))
{
hasFractionalPart = true;
} else {
hasFractionalPart = false;
}
}
}
来源：http://blog.roshka.com/2012/08/android-edittext-with-number-format.html
答案 1 :(得分：3)
您需要将DecimalFormat类与DecimalFormatSymbols类一起使用，请查看以下方法，
public static String formatAmount(int num)
{
DecimalFormat decimalFormat = new DecimalFormat();
DecimalFormatSymbols decimalFormateSymbol = new DecimalFormatSymbols();
decimalFormateSymbol.setGroupingSeparator(',');
decimalFormat.setDecimalFormatSymbols(decimalFormateSymbol);
return decimalFormat.format(num);
}
答案 2 :(得分：1)
不幸的是，代码无法按答案中的方式工作。
它有两个问题：
我疯了修复它。 最终，我找到了在手机上运行良好的这段代码：
NumberTextWatcher.java
import android.text.Editable;
import android.text.TextWatcher;
import android.text.method.DigitsKeyListener;
import android.util.Log;
import android.widget.EditText;
import java.math.RoundingMode;
import java.text.DecimalFormat;
import java.text.DecimalFormatSymbols;
import java.text.ParseException;
import java.util.Locale;
public class NumberTextWatcher
implements TextWatcher {
private static final String TAG = "NumberTextWatcher";
private final int numDecimals;
private String groupingSep;
private String decimalSep;
private boolean nonUsFormat;
private DecimalFormat df;
private DecimalFormat dfnd;
private boolean hasFractionalPart;
private EditText et;
private String value;
private String replicate(char ch, int n) {
return new String(new char[n]).replace("\0", "" + ch);
}
public NumberTextWatcher(EditText et, Locale locale, int numDecimals) {
et.setKeyListener(DigitsKeyListener.getInstance("0123456789.,"));
this.numDecimals = numDecimals;
DecimalFormatSymbols symbols = new DecimalFormatSymbols(locale);
char gs = symbols.getGroupingSeparator();
char ds = symbols.getDecimalSeparator();
groupingSep = String.valueOf(gs);
decimalSep = String.valueOf(ds);
String patternInt = "#,###";
dfnd = new DecimalFormat(patternInt, symbols);
String patternDec = patternInt + "." + replicate('#', numDecimals);
df = new DecimalFormat(patternDec, symbols);
df.setDecimalSeparatorAlwaysShown(true);
df.setRoundingMode(RoundingMode.DOWN);
this.et = et;
hasFractionalPart = false;
nonUsFormat = !decimalSep.equals(".");
value = null;
}
@Override
public void afterTextChanged(Editable s) {
Log.d(TAG, "afterTextChanged");
et.removeTextChangedListener(this);
try {
int inilen, endlen;
inilen = et.getText().length();
String v = value.replace(groupingSep, "");
Number n = df.parse(v);
int cp = et.getSelectionStart();
if (hasFractionalPart) {
int decPos = v.indexOf(decimalSep) + 1;
int decLen = v.length() - decPos;
if (decLen > numDecimals) {
v = v.substring(0, decPos + numDecimals);
}
int trz = countTrailingZeros(v);
StringBuilder fmt = new StringBuilder(df.format(n));
while (trz-- > 0) {
fmt.append("0");
}
et.setText(fmt.toString());
} else {
et.setText(dfnd.format(n));
}
endlen = et.getText().length();
int sel = (cp + (endlen - inilen));
if (sel > 0 && sel <= et.getText().length()) {
et.setSelection(sel);
} else {
// place cursor at the end?
et.setSelection(et.getText().length() - 1);
}
} catch (NumberFormatException | ParseException nfe) {
// do nothing?
}
et.addTextChangedListener(this);
}
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
Log.d(TAG, "beforeTextChanged");
value = et.getText().toString();
}
private int countTrailingZeros(String str) {
int count = 0;
for (int i = str.length() - 1; i >= 0; i--) {
char ch = str.charAt(i);
if ('0' == ch) {
count++;
} else {
break;
}
}
return count;
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
Log.d(TAG, "onTextChanged");
String newValue = s.toString();
String change = newValue.substring(start, start + count);
String prefix = value.substring(0, start);
String suffix = value.substring(start + before);
if (".".equals(change) && nonUsFormat) {
change = decimalSep;
}
value = prefix + change + suffix;
hasFractionalPart = value.contains(decimalSep);
Log.d(TAG, "VALUE: " + value);
}
}
然后简单地使用它来做：
Locale locale = new Locale("es", "AR"); // For example Argentina
int numDecs = 2; // Let's use 2 decimals
TextWatcher tw = new NumberTextWatcher(myEditText, locale, numDecs);
myEditText.addTextChangedListener(tw);
答案 3 :(得分：0)
您可以使用像这样的kotlin扩展功能...
fun EditText.onCommaChange(input: (String) -> Unit) {
this.addTextChangedListener(object : TextWatcher {
override fun afterTextChanged(s: Editable?) {
if (!edit) {
edit = true
if (s.toString() != "₹") {
try {
val flNumber = getCommaLessNumber(s.toString()).toInt()
val fNumber = getFormattedAmount(flNumber)
setText(fNumber)
setSelection(text.length)
input(flNumber.toString())
} catch (e: NumberFormatException) {
Timber.e(e)
}
} else {
setText("")
input("")
}
edit = false
}
}
override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) {}
override fun onTextChanged(s: CharSequence?, start: Int, before: Int, count: Int) {}
})}
fun getCommaLessNumber(commaNumber: String): String {
var number = commaNumber.replace("₹", "")
number = number.replace(",".toRegex(), "")
return number}
fun getFormattedAmount(amount: Int): String {
return "₹${String.format("%,d", amount)}"}
fun EditText.text() = this.text.toString()
答案 4 :(得分：0)
import android.text.Editable;
import android.text.TextWatcher;
import android.widget.EditText;
import java.text.DecimalFormat;
public class MyNumberWatcher_3Digit implements TextWatcher {
private EditText editText;
private int digit;
public MyNumberWatcher_3Digit(EditText editText) {
this.editText = editText;
}
@Override
public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
@Override
public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
@Override
public void afterTextChanged(Editable editable) {
editText.removeTextChangedListener( this );
String s = editText.getText().toString();
s = s.replace( ",", "" ).replace( "٬", "" );
s = replaceNonstandardDigits( s );
if (s.length() > 0) {
DecimalFormat sdd = new DecimalFormat( "#,###" );
Double doubleNumber = Double.parseDouble( s );
String format = sdd.format( doubleNumber );
editText.setText( format );
editText.setSelection( format.length() );
}
editText.addTextChangedListener( this );
}
static String replaceNonstandardDigits(String input) {
if (input == null || input.isEmpty()) {
return input;
}
StringBuilder builder = new StringBuilder();
for (int i = 0; i < input.length(); i++) {
char ch = input.charAt( i );
if (isNonstandardDigit( ch )) {
int numericValue = Character.getNumericValue( ch );
if (numericValue >= 0) {
builder.append( numericValue );
}
} else {
builder.append( ch );
}
}
return builder.toString();
}
private static boolean isNonstandardDigit(char ch) {
return Character.isDigit( ch ) && !(ch >= '0' && ch <= '9');
}
}
// oncreate活动
input_text_rate.addTextChangedListener(new MyNumberWatcher_3Digit(input_text_rate));
答案 5 :(得分：0)
我在 Kotlin 中使用这种方式来创建对话框：
val et = dialog.findViewById(R.id.etNumber) as EditText
et.addTextChangedListener(object : TextWatcher {
override fun afterTextChanged(s: Editable) {
et.removeTextChangedListener(this)
forChanged(et)
et.addTextChangedListener(this)
}
override fun beforeTextChanged(
s: CharSequence,
start: Int,
count: Int,
after: Int
) {
}
override fun onTextChanged(s: CharSequence, start: Int, before: Int, count: Int) {
}
})
然后写一个这样的方法：
private fun forChanged(alpha: EditText) {
val string = alpha.text.toString()
val dec = DecimalFormat("#,###")
if (!TextUtils.isEmpty(string)) {
val textWC = string.replace(",".toRegex(), "")
val number = textWC.toDouble()
alpha.setText(dec.format(number))
alpha.setSelection(dec.format(number).length)
}
}