将您的性别RadioButton s放入RadioGroup中

使用RadioGroup。您可以查看完整文档RadioGroup
您可以从developer.android.com-> http://developer.android.com/resources/tutorials/views/hello-formstuff.html#RadioButtons
例如，在xml文件中：

<RadioGroup android:layout_height="wrap_content" android:id="@+id/gender_group"
    android:layout_width="match_parent">
    <RadioButton android:text="Male"
        android:layout_width="wrap_content" android:id="@+id/radio0"
        android:layout_height="wrap_content" android:checked="true"></RadioButton>
    <RadioButton android:text="Female"
        android:layout_width="wrap_content" android:id="@+id/radio1"
        android:layout_height="wrap_content"></RadioButton>
</RadioGroup>

试试这个

public void onRadioButtonClicked(View view) {
    // Is the button now checked?
    boolean checked = ((RadioButton) view).isChecked();

    // Check which radio button was clicked
    switch(view.getId()) {
        case R.id.radio_pirates:
            if (checked)
                // Pirates are the best
            break;
        case R.id.radio_ninjas:
            if (checked)
                // Ninjas rule
            break;
    }
}

请使用Kotlin-

// Validate the gender selection
        if (!maleRadioButton.isChecked && !femaleRadioButton.isChecked) {
            Toast.makeText(this, "Please select your gender", Toast.LENGTH_SHORT).show()
            return
        }

For Better Understanding you can see this demo code - 

class ThirdActivity : AppCompatActivity() {

    private lateinit var maleRadioButton :RadioButton
    private lateinit var femaleRadioButton : RadioButton

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_third)

        // Enable the back button in the action bar
        supportActionBar?.setDisplayHomeAsUpEnabled(true)

        val button = findViewById<Button>(R.id.buttonSendData)

        //Radiobutton
        maleRadioButton = findViewById(R.id.radioMale)
        femaleRadioButton = findViewById(R.id.radioFemale)

        button.setOnClickListener {
            sendDataToFourthActivity()
        }
    }

    private fun sendDataToFourthActivity() {
        //set  userName
        val editText = findViewById<EditText>(R.id.userName)
        val username = editText.text.toString()
        //set userEmail
        val editText1 = findViewById<EditText>(R.id.userEmail)
        val userEmail = editText1.text.toString()
        //set userAge
        val editText2 = findViewById<EditText>(R.id.userAge)
        val userAge = editText2.text.toString()
        //set userMobile
        val editText3 = findViewById<EditText>(R.id.userMobile)
        val userMobile = editText3.text.toString()

        // Validate the form
       if(username.isBlank() || userEmail.isBlank() || userAge.isBlank() ||userMobile.isBlank())
       {
           Toast.makeText(this,"Please fill all the details", Toast.LENGTH_SHORT)
               .show()
           return
       }
        // Validate the gender selection
        if (!maleRadioButton.isChecked && !femaleRadioButton.isChecked) {
            Toast.makeText(this, "Please select your gender", Toast.LENGTH_SHORT).show()
            return
        }

        //Pass the RadioButton data
        val intent = Intent(this, FourthActivity::class.java)
        if (maleRadioButton.isChecked) {
            intent.putExtra("gender", "Male")
        } else if (femaleRadioButton.isChecked) {
            intent.putExtra("gender", "Female")
        }
        intent.putExtra("userName", username)
        intent.putExtra("userEmail", userEmail)
        intent.putExtra("userAge", userAge)
        intent.putExtra("userMobile", userMobile)
        startActivity(intent)

    }

    override fun onOptionsItemSelected(item: MenuItem): Boolean {
        // Handle back button clicks
        if (item.itemId == android.R.id.home) {
            onBackPressed()
            return true
        }
        return super.onOptionsItemSelected(item)
    }
}