Здесь я написал нечто похожее на то, что вам нужно:
inputBoxNumberEt.setText(". ");
inputBoxNumberEt.setSelection(inputBoxNumberEt.getText().length());
inputBoxNumberEt.addTextChangedListener(new TextWatcher() {
boolean ignoreChange = false;
@Override
public void afterTextChanged(Editable s) {
}
@Override
public void beforeTextChanged(CharSequence s, int start,
int count, int after) {
}
@Override
public void onTextChanged(CharSequence s, int start,
int before, int count) {
if (!ignoreChange) {
String string = s.toString();
string = string.replace(".", "");
string = string.replace(" ", "");
if (string.length() == 0)
string = ". ";
else if (string.length() == 1)
string = ". " + string;
else if (string.length() == 2)
string = "." + string;
else if (string.length() > 2)
string = string.substring(0, string.length() - 2) + "." + string.substring(string.length() - 2, string.length());
ignoreChange = true;
inputBoxNumberEt.setText(string);
inputBoxNumberEt.setSelection(inputBoxNumberEt.getText().length());
ignoreChange = false;
}
}
});