EditText不能输入表情

1.xml：

<EditText
android:id="@+id/editText"
android:layout_width="match_parent"
android:layout_height="300dp"
android:text="请输入内容" />

2.MainActivity

public class MainActivity extends Activity {
private EditText editText;
public InputFilter[] emojiFilters = {emojiFilter};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
editText = (EditText) findViewById(R.id.editText);
editText.setFilters(emojiFilters);
String editString=editText.getText().toString().trim();
}
private static InputFilter emojiFilter = new InputFilter() {
Pattern emoji = Pattern.compile(
"[\ud83c\udc00-\ud83c\udfff]|[\ud83d\udc00-\ud83d\udfff]|[\u2600-\u27ff]",
Pattern.UNICODE_CASE | Pattern.CASE_INSENSITIVE);
@Override
public CharSequence filter(CharSequence source, int start, int end, Spanned dest,
int dstart,
int dend) {
Matcher emojiMatcher = emoji.matcher(source);
if (emojiMatcher.find()) {
return "";
}
return null;
}
};
}