我们可以认为这是一个很人性的格式化操作，在ComposeMessageActivity中系统在调用initRecipientsEditor（）方法对联系人进行初始化的时候调用了 PhoneNumberFormatter.setPhoneNumberFormattingTextWatcher(this, mRecipientsEditor);我们通过对代码进行追踪发现，最终调用了Framework中PhoneNumberFormattingTextWatcher类对电话号码进行格式化处理，并在处理后在PhoneNumberFormatter中使用异步类控件的值进行处理，这里贴处该类的代码进行分析。
package android.telephony;
import com.android.i18n.phonenumbers.AsYouTypeFormatter;
import com.android.i18n.phonenumbers.PhoneNumberUtil;
import android.telephony.PhoneNumberUtils;
import android.text.Editable;
import android.text.Selection;
import android.text.TextWatcher;
import java.util.Locale;
/**
* Watches a {@link android.widget.TextView} and if a phone number is entered
* will format it.
* <p>
* Stop formatting when the user
* <ul>
* <li>Inputs non-dialable characters</li>
* <li>Removes the separator in the middle of string.</li>
* </ul>
* <p>
* The formatting will be restarted once the text is cleared.
*/
public class PhoneNumberFormattingTextWatcher implements TextWatcher {
/**
* Indicates the change was caused by ourselves.
*/
private boolean mSelfChange = false;
/**
* Indicates the formatting has been stopped.
*/
private boolean mStopFormatting;
private AsYouTypeFormatter mFormatter;
/**
* The formatting is based on the current system locale and future locale changes
* may not take effect on this instance.
*/
public PhoneNumberFormattingTextWatcher() {
this(Locale.getDefault().getCountry());
}
/**
* The formatting is based on the given <code>countryCode</code>.
*
* @param countryCode the ISO 3166-1 two-letter country code that indicates the country/region
* where the phone number is being entered.
*
* @hide
*/
public PhoneNumberFormattingTextWatcher(String countryCode) {
if (countryCode == null) throw new IllegalArgumentException();
mFormatter = PhoneNumberUtil.getInstance().getAsYouTypeFormatter(countryCode);
}
@Override
public void beforeTextChanged(CharSequence s, int start, int count,
int after) {
if (mSelfChange || mStopFormatting) {
return;
}
// If the user manually deleted any non-dialable characters, stop formatting
if (count > 0 && hasSeparator(s, start, count)) {
stopFormatting();
}
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
if (mSelfChange || mStopFormatting) {
return;
}
// If the user inserted any non-dialable characters, stop formatting
if (count > 0 && hasSeparator(s, start, count)) {
stopFormatting();
}
}
@Override
public synchronized void afterTextChanged(Editable s) {
if (mStopFormatting) {
// Restart the formatting when all texts were clear.
mStopFormatting = !(s.length() == 0);
return;
}
if (mSelfChange) {
// Ignore the change caused by s.replace().
return;
}
String formatted = reformat(s, Selection.getSelectionEnd(s));
if (formatted != null) {
int rememberedPos = mFormatter.getRememberedPosition();
mSelfChange = true;
s.replace(0, s.length(), formatted, 0, formatted.length());
// The text could be changed by other TextWatcher after we changed it. If we found the
// text is not the one we were expecting, just give up calling setSelection().
if (formatted.equals(s.toString())) {
Selection.setSelection(s, rememberedPos);
}
mSelfChange = false;
}
}
/**
* Generate the formatted number by ignoring all non-dialable chars and stick the cursor to the
* nearest dialable char to the left. For instance, if the number is (650) 123-45678 and '4' is
* removed then the cursor should be behind '3' instead of '-'.
*/
private String reformat(CharSequence s, int cursor) {
// The index of char to the leftward of the cursor.
int curIndex = cursor - 1;
String formatted = null;
mFormatter.clear();
char lastNonSeparator = 0;
boolean hasCursor = false;
int len = s.length();
for (int i = 0; i < len; i++) {
char c = s.charAt(i);
if (PhoneNumberUtils.isNonSeparator(c)) {
if (lastNonSeparator != 0) {
formatted = getFormattedNumber(lastNonSeparator, hasCursor);
hasCursor = false;
}
lastNonSeparator = c;
}
if (i == curIndex) {
hasCursor = true;
}
}
if (lastNonSeparator != 0) {
formatted = getFormattedNumber(lastNonSeparator, hasCursor);
}
return formatted;
}
private String getFormattedNumber(char lastNonSeparator, boolean hasCursor) {
return hasCursor ? mFormatter.inputDigitAndRememberPosition(lastNonSeparator)
: mFormatter.inputDigit(lastNonSeparator);
}
private void stopFormatting() {
mStopFormatting = true;
mFormatter.clear();
}
private boolean hasSeparator(final CharSequence s, final int start, final int count) {
for (int i = start; i < start + count; i++) {
char c = s.charAt(i);
if (!PhoneNumberUtils.isNonSeparator(c)) {
return true;
}
}
return false;
}
}
通过查看PhoneNumberFormattingTextWatcher代码我们发现，该类继承至TextWatcher，则实现了对RecipientEditor的值的变化进行了监听，最后调用PhoneNumberUtils进行处理。