android扫描所有wifi网络并列出ssid

Question

我想列出所有 wifi 网络并在列表中显示 ssid。我认为我应该使用广播来执行此操作，但我使用了几个代码但不起作用。我只需要列出所有 sside 并将它们显示给用户但是如果你告诉我如何显示 wifi 信号也很强大，它会很棒。 我使用此代码但不起作用：

    public class WiFiDemo extends AppCompatActivity implements View.OnClickListener {
    WifiManager wifi;
    ListView lv;
    TextView textStatus;
    Button buttonScan;
    int size = 0;
    List<ScanResult> results;

    String ITEM_KEY = "key";
    ArrayList<HashMap<String, String>> arraylist = new ArrayList<HashMap<String, String>>();
    SimpleAdapter adapter;

    /* Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.wifidemo);

        textStatus = (TextView) findViewById(R.id.textStatus);
        buttonScan = (Button) findViewById(R.id.buttonScan);
        buttonScan.setOnClickListener(this);
        lv = (ListView) findViewById(R.id.list);

        wifi = (WifiManager) getApplicationContext().getSystemService(Context.WIFI_SERVICE);
        if (wifi.isWifiEnabled() == false) {
            Toast.makeText(getApplicationContext(), "wifi is disabled..making it enabled", Toast.LENGTH_LONG).show();
            wifi.setWifiEnabled(true);
        }
        this.adapter = new SimpleAdapter(WiFiDemo.this, arraylist, R.layout.row, new String[]{ITEM_KEY}, new int[]{R.id.list_value});
        lv.setAdapter(this.adapter);

        registerReceiver(new BroadcastReceiver() {
            @Override
            public void onReceive(Context c, Intent intent) {
                results = wifi.getScanResults();
                size = results.size();
            }
        }, new IntentFilter(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION));
    }

    public void onClick(View view) {
        arraylist.clear();
        wifi.startScan();

        Toast.makeText(this, "Scanning...." + size, Toast.LENGTH_SHORT).show();
        try {
            size = size - 1;
            while (size >= 0) {
                HashMap<String, String> item = new HashMap<String, String>();
                item.put(ITEM_KEY, results.get(size).SSID + "  " + results.get(size).capabilities);

                arraylist.add(item);
                size--;
                adapter.notifyDataSetChanged();
            }
        } catch (Exception e) {
        }
    }
}

Answer 1

您确定获得此权限吗？

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