编程实现 Android 手机上 WiFi 操作，实现WiFi 管理界面及功能

要实现 Android 手机上 WiFi 操作，首先需要在 Android 应用程序中添加 WiFi 权限：

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

然后，可以通过以下代码获取 WiFiManager 对象：

WifiManager wifiManager = (WifiManager) getApplicationContext().getSystemService(Context.WIFI_SERVICE);

使用 WiFiManager 对象可以完成 WiFi 相关的操作，例如获取当前连接的 WiFi 热点信息：

WifiInfo wifiInfo = wifiManager.getConnectionInfo();
String ssid = wifiInfo.getSSID();
int signalStrength = wifiInfo.getRssi();

还可以获取当前可用的 WiFi 热点列表：

List<ScanResult> scanResults = wifiManager.getScanResults();

接下来，可以创建一个 WiFi 管理界面，显示当前连接的 WiFi 热点信息和可用的 WiFi 热点列表，并提供连接、断开连接等操作。

具体实现可以参考以下代码示例：

public class WifiActivity extends Activity {

    private WifiManager wifiManager;
    private ListView listView;
    private List<ScanResult> scanResults;
    private ScanResultAdapter adapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_wifi);

        wifiManager = (WifiManager) getApplicationContext().getSystemService(Context.WIFI_SERVICE);
        listView = findViewById(R.id.list_view);

        adapter = new ScanResultAdapter(this);
        listView.setAdapter(adapter);
        listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                ScanResult scanResult = scanResults.get(position);
                WifiConfiguration wifiConfiguration = new WifiConfiguration();
                wifiConfiguration.SSID = "\"" + scanResult.SSID + "\"";
                wifiConfiguration.preSharedKey = "\"" + "password" + "\"";
                int networkId = wifiManager.addNetwork(wifiConfiguration);
                wifiManager.disconnect();
                wifiManager.enableNetwork(networkId, true);
                wifiManager.reconnect();
            }
        });

        Button connectButton = findViewById(R.id.connect_button);
        connectButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                EditText ssidEditText = findViewById(R.id.ssid_edit_text);
                EditText passwordEditText = findViewById(R.id.password_edit_text);
                String ssid = ssidEditText.getText().toString();
                String password = passwordEditText.getText().toString();
                WifiConfiguration wifiConfiguration = new WifiConfiguration();
                wifiConfiguration.SSID = "\"" + ssid + "\"";
                wifiConfiguration.preSharedKey = "\"" + password + "\"";
                int networkId = wifiManager.addNetwork(wifiConfiguration);
                wifiManager.disconnect();
                wifiManager.enableNetwork(networkId, true);
                wifiManager.reconnect();
            }
        });

        Button disconnectButton = findViewById(R.id.disconnect_button);
        disconnectButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                wifiManager.disconnect();
            }
        });

        Button refreshButton = findViewById(R.id.refresh_button);
        refreshButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                scanResults = wifiManager.getScanResults();
                adapter.setScanResults(scanResults);
                adapter.notifyDataSetChanged();
            }
        });
    }

    private static class ScanResultAdapter extends BaseAdapter {

        private Context context;
        private List<ScanResult> scanResults;

        public ScanResultAdapter(Context context) {
            this.context = context;
            scanResults = new ArrayList<>();
        }

        public void setScanResults(List<ScanResult> scanResults) {
            this.scanResults = scanResults;
        }

        @Override
        public int getCount() {
            return scanResults.size();
        }

        @Override
        public Object getItem(int position) {
            return scanResults.get(position);
        }

        @Override
        public long getItemId(int position) {
            return position;
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            if (convertView == null) {
                convertView = LayoutInflater.from(context).inflate(R.layout.item_scan_result, parent, false);
            }
            TextView ssidTextView = convertView.findViewById(R.id.ssid_text_view);
            TextView signalStrengthTextView = convertView.findViewById(R.id.signal_strength_text_view);
            ScanResult scanResult = scanResults.get(position);
            ssidTextView.setText(scanResult.SSID);
            signalStrengthTextView.setText(String.valueOf(scanResult.level));
            return convertView;
        }
    }
}

在 layout 目录下创建 activity_wifi.xml 文件，定义 WiFi 管理界面的布局：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <EditText
        android:id="@+id/ssid_edit_text"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="SSID"/>

    <EditText
        android:id="@+id/password_edit_text"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="Password"/>

    <Button
        android:id="@+id/connect_button"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Connect"/>

    <Button
        android:id="@+id/disconnect_button"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Disconnect"/>

    <Button
        android:id="@+id/refresh_button"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Refresh"/>

    <ListView
        android:id="@+id/list_view"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>
</LinearLayout>

在 layout 目录下创建 item_scan_result.xml 文件，定义 WiFi 热点列表项的布局：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal">

    <TextView
        android:id="@+id/ssid_text_view"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:text="SSID"/>

    <TextView
        android:id="@+id/signal_strength_text_view"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Signal Strength"/>

</LinearLayout>

这样就完成了 Android 手机上 WiFi 操作的实现。