如何基于联网/断网创建 Android 设备网络监听器?
androidapps/applicationsmobile development更新于 2026/2/16 15:07:17
此示例演示了如何基于联网/断网创建 Android 设备网络监听器。
步骤 1 − 在 Android Studio 中创建一个新项目，前往"文件"->"新建项目"，并填写所有必填信息以创建新项目。
步骤 2 − 将以下代码添加到 res/layout/activity_main.xml
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" android:padding="16sp" tools:context=".MainActivity"> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginTop="30dp" android:text="Android Device Network Listener based on on/off network" android:textSize="24sp" android:textStyle="bold" /> <Button android:layout_marginTop="30dp" android:onClick="SwitchWIFION" android:layout_width="match_parent" android:layout_height="wrap_content" android:text="Switch on Wifi"/> <Button android:layout_marginTop="10dp" android:onClick="SwitchWIFIOFF" android:layout_width="match_parent" android:layout_height="wrap_content" android:text="Switch on Wifi"/< </LinearLayout>
步骤 3 − 将以下代码添加到 src/MainActivity.java
import androidx.appcompat.app.AppCompatActivity;
import android.content.Context;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.net.wifi.WifiManager;
import android.os.Bundle;
import android.view.View;
import android.widget.Toast;
import java.util.Objects;
public class MainActivity extends AppCompatActivity {
WifiManager wifiManager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
wifiManager = (WifiManager) getApplicationContext().getSystemService(WIFI_SERVICE);
ConnectivityManager connectivityManager = (ConnectivityManager)
getApplicationContext().getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo activeNetInfo =
Objects.requireNonNull(connectivityManager).getActiveNetworkInfo();
NetworkInfo mobNetInfo =
connectivityManager.getNetworkInfo(ConnectivityManager.TYPE_MOBILE);
if (activeNetInfo != null) {
Toast.makeText(getApplicationContext(), "Active Network Type : " +
activeNetInfo.getTypeName(), Toast.LENGTH_SHORT).show();
}
if (mobNetInfo != null) {
Toast.makeText(getApplicationContext(), "Mobile Network Type : " +
mobNetInfo.getTypeName(), Toast.LENGTH_SHORT).show();
}
}
public void SwitchWIFION(View view) {
Objects.requireNonNull(wifiManager).setWifiEnabled(true);
Toast.makeText(getApplicationContext(), "WIFI SWITCHED ON",
Toast.LENGTH_SHORT).show();
}
public void SwitchWIFIOFF(View view) {
Objects.requireNonNull(wifiManager).setWifiEnabled(false);
Toast.makeText(getApplicationContext(), "WIFI SWITCHED OFF",
Toast.LENGTH_SHORT).show();
}
}
步骤 4 − 将以下代码添加到 androidManifest.xml
<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="app.com.sample"> <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> <uses-permission android:name="android.permission.CHANGE_WIFI_STATE" /> <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" /> </manifest>
让我们尝试运行您的应用程序。假设您已将实际的 Android 移动设备连接到电脑。要从 Android Studio 运行该应用程序，请打开项目的某个活动文件，然后点击工具栏上的"运行"
图标。选择您的移动设备作为选项，然后检查您的移动设备是否显示您的默认屏幕 −
