在Kotlin

Question

我想在某些事件发生时向用户发送电子邮件，我在Internet上搜索，但找不到该方法。 谁能告诉我正确的道路。

Answer 1

然后我刚刚在我想向用户发送电子邮件的活动中实施。 提示：使用最新版本的Javamail，不要忘记在清单文件中打开Internet许可

   private fun sendMail(etEmail: EditText, etSubject: EditText, etMessage: EditText) {



        // Set up the mail server
        val host = "smtp.sendgrid.net"
        val props = Properties().apply {
            put("mail.smtp.auth", "true")
            put("mail.smtp.ssl.enable", "true")
            put("mail.smtp.host", host)
            put("mail.smtp.port", "465")
        }

        // Set up authentication
        val session = Session.getInstance(props, object : Authenticator() {
            override fun getPasswordAuthentication() =
                PasswordAuthentication("apikey","yourpaswordxyzfromsendgridaccount")
        })

        try {
            // Create a default MimeMessage object
            val message = MimeMessage(session).apply {
                setFrom(InternetAddress("abc@xyz"))
                addRecipient(Message.RecipientType.TO, InternetAddress(etEmail.text.toString()))
                subject = etSubject.text.toString()
                setText(etMessage.text.toString())
            }

            // Send the message
            thread(start = true) {
                Transport.send(message)
                println("Email sent successfully.")

                println("running from thread(): ${Thread.currentThread()}")
            }
            Toast.makeText(this,"Mail sent",Toast.LENGTH_LONG).show()



        } catch (e: MessagingException) {
            e.printStackTrace()
        }


}

build.gradle.kts

Answer 2

dependencies {
 
    implementation("com.sun.mail:android-mail:1.6.2")
    implementation("com.sun.mail:android-activation:1.6.2") // important
}

AndroidManifest.xml

中的第二秒

<uses-permission android:name="android.permission.INTERNET" />

三分之二创建一个类（ex。：MailService）

import android.os.StrictMode
import java.util.Properties
import javax.mail.Authenticator
import javax.mail.Message
import javax.mail.PasswordAuthentication
import javax.mail.Session
import javax.mail.Transport
import javax.mail.internet.InternetAddress
import javax.mail.internet.MimeMessage

class MailService {
    // function send email
    fun sendEmail() {
        val username = "[email protected]" // replace with your email
        val password = "your_email_password" // replace with your password email
        val recipient = "[email protected]" // replace with recipient email
        // properties
        val props = Properties()
        props["mail.smtp.host"] = "smtp.mail.com" // replace with your SMTP server
        props["mail.smtp.port"] = "465" // replace with your SMTP port
        props["mail.smtp.auth"] = "true"
        props["mail.smtp.starttls.enable"] = "true"
        props["mail.smtp.socketFactory.port"] = "465" // replace with your SMTP port
        props["mail.smtp.socketFactory.class"] = "javax.net.ssl.SSLSocketFactory"
        // session
        val session = Session.getDefaultInstance(props, object: Authenticator() {
            override fun getPasswordAuthentication(): PasswordAuthentication {
                return PasswordAuthentication(username, password)
            }
        })
        // policy
        val policy = StrictMode.ThreadPolicy.Builder().permitAll().build()
        StrictMode.setThreadPolicy(policy)
        // send message
        try {
            val email = MimeMessage(session)
            email.setFrom(InternetAddress(username))
            email.addRecipient(Message.RecipientType.TO, InternetAddress(recipient))
            email.subject = "Title Email" // email title
            email.setText("Test Email Body"// email body) 
            Transport.send(email)
            println("SUCCESS: Email sent successfully!")
        } catch (e: Exception) {
            println("ERROR: Fail sending email: ${e.message}")
            e.printStackTrace()
        }
    }

}

在MainAttivity中获得最高的作用

class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        enableEdgeToEdge()
        setContentView(R.layout.activity_main)
        ViewCompat.setOnApplyWindowInsetsListener(findViewById(R.id.main)) { v, insets ->
            val systemBars = insets.getInsets(WindowInsetsCompat.Type.systemBars())
            v.setPadding(systemBars.left, systemBars.top, systemBars.right, systemBars.bottom)
            insets
        }
        // button
        val button = findViewById<Button>(R.id.button)
        // send email after click button
        button.setOnClickListener {
            val mailService = MailService()
            mailService.sendEmail()
        }

    }

}

我希望我能帮助你，