private static final char kongge = ' '; private TextWatcher textWatcher=new TextWatcher() {
  //改变之前text长度  int beforeTextLength = 0;  //改变之前的文字  private CharSequence beforeChar;  //改变之后text长度  int onTextLength = 0;  //是否改变空格或光标  boolean isChanged = false;  // 记录光标的位置  int location = 0;     private char[] tempChar;     private StringBuffer buffer = new StringBuffer();  //已有空格数量  int konggeNumberB = 0;  @Override  public void beforeTextChanged(CharSequence s, int start, int count, int after) {
  beforeTextLength = s.length();         if (buffer.length() > 0) {
  buffer.delete(0, buffer.length());  } konggeNumberB = 0;         for (int i = 0; i < s.length(); i++) {
  if (s.charAt(i) == ' ') {
  konggeNumberB++;  }         }     } @Override  public void onTextChanged(CharSequence s, int start, int before, int count) {
  onTextLength = s.length();  buffer.append(s.toString());         if (onTextLength == beforeTextLength || onTextLength <= 3  || isChanged) {
  isChanged = false;             return;  } isChanged = true;  } @Override  public void afterTextChanged(Editable s) {
  if (isChanged) {
  location = yourCardNumEd.getSelectionEnd();             int index = 0;             while (index < buffer.length()) {
  if (buffer.charAt(index) == kongge) {
  buffer.deleteCharAt(index);  } else {
                      index++;  }             }             index = 0;             int konggeNumberC = 0;             while (index < buffer.length()) {
  if ((index == 4 || index == 9 || index == 14 || index == 19)) {
  buffer.insert(index, kongge);  konggeNumberC++;  }                 index++;  } if (konggeNumberC > konggeNumberB) {
  location += (konggeNumberC - konggeNumberB);  } tempChar = new char[buffer.length()];  buffer.getChars(0, buffer.length(), tempChar, 0);  String str = buffer.toString();             if (location > str.length()) {
  location = str.length();  } else if (location < 0) {
  location = 0;  } yourCardNumEd.setText(str);  Editable etable = yourCardNumEd.getText();             if (location>20){
                  ToastUtil.ToastShow("最多才能输入20位");                 return;  }             Selection.setSelection(etable, location);             isChanged = false;  }     } };