EditText判断手机格式及下面按钮的变色

pass.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {

}

@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {

}

@Override
public void afterTextChanged(Editable s) {
if (s.length()==0){
mylogin.setBackgroundColor(Color.parseColor("#CACACA"));
//delete_edit2.setVisibility(View.INVISIBLE);
mylogin.setTextColor(Color.WHITE);
}else{
//delete_edit2.setVisibility(View.VISIBLE);
String pas=phonenum.getText().toString();
int l=pas.length();
if (l>0){
mylogin.setBackgroundColor(Color.parseColor("#EDA200"));
mylogin.setTextColor(Color.WHITE);
}
}

}
});

phonenum.addTextChangedListener(new TextWatcher() {
@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 (s == null || s.length() == 0)
return;
StringBuilder sb = new StringBuilder();
for (int i = 0; i < s.length(); i++) {
if (i != 3 && i != 8 && s.charAt(i) == ' ') {
continue;
} else {
sb.append(s.charAt(i));
if ((sb.length() == 4 || sb.length() == 9)
&& sb.charAt(sb.length() - 1) != ' ') {
sb.insert(sb.length() - 1, ' ');
}
}
}
if (!sb.toString().equals(s.toString())) {
int index = start + 1;
if (sb.charAt(start) == ' ') {
if (before == 0) {
index++;
} else {
index--;
}
} else {
if (before == 1) {
index--;
}
}
phonenum.setText(sb.toString());
phonenum.setSelection(index);
}
}