Android-尝试发送电子邮件时收到错误消息“没有应用程序可以执行此操作”？

public void emailDialog()
{
    AlertDialog.Builder alertDialog = new AlertDialog.Builder(this);
    alertDialog.setTitle(\"Feedback\");
    alertDialog.setMessage(\"Please tell us that what you feel about our product. If you are facing any problem or found any bug then please report to us. Your review is important to us. Thanks!!\");
    final EditText input = new EditText(this);
    input.setLines(8);
    alertDialog.setView(input);
    alertDialog.setPositiveButton(\"Ok\", new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int whichButton) {
            String value = input.getText().toString();
            String address = \"varundroid@gmail.com\";
            String subject = \"FeedBack\";
            final Intent emailIntent = new Intent(android.content.Intent.ACTION_SEND);
            emailIntent.putExtra(android.content.Intent.EXTRA_EMAIL, address);
            emailIntent.putExtra(android.content.Intent.EXTRA_SUBJECT, subject);
            emailIntent.putExtra(android.content.Intent.EXTRA_TEXT, value);
            CompleteTaskManager.this.startActivity(Intent.createChooser(emailIntent, \"Send Email..\"));
        }
    });
    alertDialog.setNegativeButton(\"Cancel\", new DialogInterface.OnClickListener() {
      public void onClick(DialogInterface dialog, int whichButton) {
        // Canceled.
      }
    });
alertDialog.show();
}