Cách lấy thông tin Host (máy chủ build) Android bằng lập trình

Giới thiệu

Hướng dẫn này trình bày cách lấy thông tin Host (tên máy chủ/build server) nơi bản firmware Android được biên dịch. Thông tin này nằm trong Build.HOST.

Các bước thực hiện

Bước 1: Tạo dự án mới

Tạo dự án Android Studio: File → New Project.

Bước 2: Layout activity_main.xml

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

    <TextView
        android:id="@+id/text"
        android:textSize="30sp"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

</LinearLayout>

Bước 3: MainActivity.java

package com.example.myapplication;

import android.Manifest;
import android.content.pm.PackageManager;
import android.os.Build;
import android.os.Bundle;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.app.ActivityCompat;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

    TextView textView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        textView = findViewById(R.id.text);

        if (ActivityCompat.checkSelfPermission(this, Manifest.permission.READ_PHONE_STATE) 
                != PackageManager.PERMISSION_GRANTED) {
            ActivityCompat.requestPermissions(this, 
                new String[]{Manifest.permission.READ_PHONE_STATE}, 101);
        } else {
            showHostInfo();
        }
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        if (requestCode == 101) {
            if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                showHostInfo();
            }
        }
    }

    private void showHostInfo() {
        try {
            String host = Build.HOST;
            textView.setText("Build Host: " + host);
        } catch (SecurityException e) {
            textView.setText("Không có quyền truy cập Build.HOST");
            e.printStackTrace();
        }
    }

    @Override
    protected void onResume() {
        super.onResume();
        if (ActivityCompat.checkSelfPermission(this, Manifest.permission.READ_PHONE_STATE) 
                == PackageManager.PERMISSION_GRANTED) {
            showHostInfo();
        }
    }
}

Bước 4: AndroidManifest.xml

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

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