MailActivity.java

//先跳转到邮件
Intent intent = new Intent(Intent.ACTION_SENDTO);
intent.setData(Uri.parse("mailto:[email protected]"));
//判断能否跳转
if (intent.resolveActivity(getPackageManager()) != null) { //可以接收
    intent.putExtra(Intent.EXTRA_SUBJECT, "邮件标题");
    intent.putExtra(Intent.EXTRA_TEXT, "邮件正文啦啦啦~");
    startActivity(intent);
} else { //不能跳转
    Toast.makeText(this, "没有安装邮件客户端", Toast.LENGTH_SHORT).show();
}