package android.text.util;
import android.text.InputFilter;
import android.text.Spanned;
import android.text.SpannableStringBuilder;
/**
* Implements special address cleanup rules:
* The first space key entry following an "@" symbol that is followed by any combination
* of letters and symbols, including one+ dots and zero commas, should insert an extra
* comma (followed by the space).
*
* @hide
*/
public class Rfc822InputFilter implements InputFilter {
public CharSequence filter(CharSequence source, int start, int end, Spanned dest,
int dstart, int dend) {
// quick check - did they enter a single space?
if (end-start != 1 || source.charAt(start) != ' ') {
return null;
}
// determine if the characters before the new space fit the pattern
// follow backwards and see if we find a comma, dot, or @
int scanBack = dstart;
boolean dotFound = false;
while (scanBack > 0) {
char c = dest.charAt(--scanBack);
switch (c) {
case '.':
dotFound = true; // one or more dots are req'd
break;
case ',':
return null;
case '@':
if (!dotFound) {
return null;
}
// we have found a comma-insert case. now just do it
// in the least expensive way we can.
if (source instanceof Spanned) {
SpannableStringBuilder sb = new SpannableStringBuilder(",");
sb.append(source);
return sb;
} else {
return ", ";
}
default:
// just keep going
}
}
// no termination cases were found, so don't edit the input
return null;
}
}