简单，试试这个

 public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    buttonSend = (Button) findViewById(R.id.buttonSend);
    textTo = (EditText) findViewById(R.id.editTextTo);
    textSubject = (EditText) findViewById(R.id.editTextSubject);
    textMessage = (EditText) findViewById(R.id.editTextMessage);

    buttonSend.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {

            String to = textTo.getText().toString();
            String subject = textSubject.getText().toString();
            String message = textMessage.getText().toString();

            Intent email = new Intent(Intent.ACTION_SEND);
            email.putExtra(Intent.EXTRA_EMAIL, new String[] { to });
            // email.putExtra(Intent.EXTRA_CC, new String[]{ to});
            // email.putExtra(Intent.EXTRA_BCC, new String[]{to});
            email.putExtra(Intent.EXTRA_SUBJECT, subject);
            email.putExtra(Intent.EXTRA_TEXT, message);

            // need this to prompts email client only
            email.setType("message/rfc822");

            startActivity(Intent.createChooser(email, "Choose an Email client :"));

        }
    });
}

使用这个发送电子邮件…

boolean success = EmailIntentBuilder.from(activity)
    .to("support@example.org")
    .cc("developer@example.org")
    .subject("Error report")
    .body(buildErrorReport())
    .start();

使用build gradle:

compile 'de.cketti.mailto:email-intent-builder:1.0.0'

 Intent emailIntent = new Intent(Intent.ACTION_SENDTO, Uri.fromParts(
            "mailto","ebgsoldier@gmail.com", null));
    emailIntent.putExtra(Intent.EXTRA_SUBJECT, "Forgot Password");
    emailIntent.putExtra(Intent.EXTRA_TEXT, "this is a text ");
    startActivity(Intent.createChooser(emailIntent, "Send email..."));

Kotlin版本，只显示电子邮件客户端(没有联系人等):

    with(Intent(Intent.ACTION_SEND)) {
        type = "message/rfc822"
        data = Uri.parse("mailto:")
        putExtra(Intent.EXTRA_EMAIL, arrayOf("user@example.com"))
        putExtra(Intent.EXTRA_SUBJECT,"YOUR SUBJECT")
        putExtra(Intent.EXTRA_TEXT, "YOUR BODY")
        try {
            startActivity(Intent.createChooser(this, "Send Email with"))
        } catch (ex: ActivityNotFoundException) {
            // No email clients found, might show Toast here
        }
    }

简单，试试这个

 public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    buttonSend = (Button) findViewById(R.id.buttonSend);
    textTo = (EditText) findViewById(R.id.editTextTo);
    textSubject = (EditText) findViewById(R.id.editTextSubject);
    textMessage = (EditText) findViewById(R.id.editTextMessage);

    buttonSend.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {

            String to = textTo.getText().toString();
            String subject = textSubject.getText().toString();
            String message = textMessage.getText().toString();

            Intent email = new Intent(Intent.ACTION_SEND);
            email.putExtra(Intent.EXTRA_EMAIL, new String[] { to });
            // email.putExtra(Intent.EXTRA_CC, new String[]{ to});
            // email.putExtra(Intent.EXTRA_BCC, new String[]{to});
            email.putExtra(Intent.EXTRA_SUBJECT, subject);
            email.putExtra(Intent.EXTRA_TEXT, message);

            // need this to prompts email client only
            email.setType("message/rfc822");

            startActivity(Intent.createChooser(email, "Choose an Email client :"));

        }
    });
}

下面是在android设备中打开邮件应用程序并在编写邮件时自动填充To address和Subject的示例工作代码。

protected void sendEmail() {
    Intent intent = new Intent(Intent.ACTION_SENDTO);
    intent.setData(Uri.parse("mailto:feedback@gmail.com"));
    intent.putExtra(Intent.EXTRA_SUBJECT, "Feedback");
    if (intent.resolveActivity(getPackageManager()) != null) {
        startActivity(intent);
    }
}