public void insertEmotion(String emotionChar) {
   String ori = content.getText().toString();
   int index = content.getSelectionStart();
   StringBuilder stringBuilder = new StringBuilder(ori);
   stringBuilder.insert(index, emotionChar);
   content.setText(stringBuilder.toString());
   content.setSelection(index + emotionChar.length());
 }
  protected void onActivityResult(int requestCode, int resultCode, Intent intent) {
    super.onActivityResult(requestCode, resultCode, intent);

    if (resultCode == RESULT_OK) {
      switch (requestCode) {
        case CAMERA_RESULT:
          if (TextUtils.isEmpty(content.getText().toString())) {
            content.setText(getString(R.string.share_pic));
            content.setSelection(content.getText().toString().length());
          }

          picPath = getPicPathFromUri(imageFileUri);
          havePic.setVisibility(View.VISIBLE);
          break;
        case PIC_RESULT:
          if (TextUtils.isEmpty(content.getText().toString())) {
            content.setText(getString(R.string.share_pic));
            content.setSelection(content.getText().toString().length());
          }

          Uri imageFileUri = intent.getData();
          picPath = getPicPathFromUri(imageFileUri);
          havePic.setVisibility(View.VISIBLE);
          break;
        case AT_USER:
          String name = intent.getStringExtra("name");
          String ori = content.getText().toString();
          int index = content.getSelectionStart();
          StringBuilder stringBuilder = new StringBuilder(ori);
          stringBuilder.insert(index, name);
          content.setText(stringBuilder.toString());
          content.setSelection(index + name.length());
          break;
      }
    }
  }