Lấy địa chỉ IP của Android Emulator bằng Kotlin

Giới thiệu

Ví dụ này demo cách lấy địa chỉ IP của trình giả lập Android (Emulator) sử dụng Kotlin.

Bước 1: Tạo dự án mới

Android Studio → File → New Project.

Bước 2: Layout (res/layout/activity_main.xml)

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="https://schemas.android.com/apk/res/android"
    xmlns:tools="https://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="70dp"
        android:background="#008080"
        android:padding="5dp"
        android:text="TutorialsPoint"
        android:textColor="#fff"
        android:textSize="24sp"
        android:textStyle="bold" />

    <TextView
        android:id="@+id/textView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerInParent="true"
        android:textColor="@android:color/background_dark"
        android:textSize="16sp"
        android:textStyle="bold" />

    <Button
        android:id="@+id/btnGetIPAddress"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/textView"
        android:layout_centerInParent="true"
        android:layout_marginTop="10dp"
        android:text="Get IP Address" />

</RelativeLayout>

Bước 3: Code Kotlin (src/MainActivity.kt)

import android.net.wifi.WifiManager
import android.os.Bundle
import android.widget.Button
import android.widget.TextView
import androidx.appcompat.app.AppCompatActivity
import android.text.format.Formatter

class MainActivity : AppCompatActivity() {
    private lateinit var button: Button
    private lateinit var textView: TextView

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        title = "KotlinApp"

        textView = findViewById(R.id.textView)
        button = findViewById(R.id.btnGetIPAddress)

        button.setOnClickListener {
            val wifiManager = applicationContext.getSystemService(WIFI_SERVICE) as WifiManager
            val ip = Formatter.formatIpAddress(wifiManager.connectionInfo.ipAddress)
            textView.text = String.format("IP Address: %s", ip)
        }
    }
}

Bước 4: AndroidManifest.xml (quyền truy cập WiFi)

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="https://schemas.android.com/apk/res/android"
    package="com.example.q11">

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

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">

        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

    </application>
</manifest>

Chạy ứng dụng

Kết nối thiết bị, nhấn Run . Nhấn nút "Get IP Address" để hiển thị IP của emulator/thiết bị.