答案 0 :(得分:1)
您需要为您的Activity注册BroadcastReceiver,但在您需要添加访问网络状态的权限并在清单中修改它之前:
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE"></uses-permission>
<uses-permission android:name="android.permission.CHANGE_WIFI_STATE"></uses-permission>
在我们创建BroadcastReceiver
之前,我们需要设置一些内容:
ArrayList<String> ssidList;
WifiManager wifiManager;
WifiScanReceiver wifiReciever;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_options);
//Wifi manager will be used to request a scan
wifiManager = (WifiManager) getSystemService(Context.WIFI_SERVICE);
//Your boradcast receiver, it will be registered with the system to be notified of SSID's available
wifiReciever = new WifiScanReceiver();
//A list to add all the available SSID's
ssidList = new ArrayList<String>();
//Requesting a scan, results will be returned through the BroadcastReceiver
wifiManager.startScan();
}
这是您的BoradcastReceiver
class WifiScanReceiver extends BroadcastReceiver {
public void onReceive(Context c, Intent intent) {
List<ScanResult> wifiScanList = wifiManager.getScanResults();
ssidList.clear(); // clear to make sure we do not get duplicated entries
for (int i = 0; i < wifiScanList.size(); i++) {
String ssid = wifiScanList.get(i).SSID; //Get the SSID
ssidList.add(ssid); //add SSID to the list
Log.d("SSID", ssid);
}
//You can call this to keep scaning if you need to, or you can set up a Timer to scan every X seconds
//wifiManager.startScan();
}
}
您需要在应用调用onResume
时优先注册BroadcastReceiver,并在调用onPause
时取消注册:
protected void onPause() {
unregisterReceiver(wifiReciever);
super.onPause();
}
protected void onResume() {
registerReceiver(wifiReciever, new IntentFilter(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION));
super.onResume();
}
这是完整的代码:
public class WifiActivity extends AppCompatActivity {
ArrayList<String> ssidList;
WifiManager wifiManager;
WifiScanReceiver wifiReciever;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//Wifi manager will be used to request a scan
wifiManager = (WifiManager) getSystemService(Context.WIFI_SERVICE);
//Your boradcast receiver, it will be registered with the system to be notified of SSID's available
wifiReciever = new WifiScanReceiver();
//A list to add all the available SSID's
ssidList = new ArrayList<String>();
//Requesting a scan, results will be returned through the BroadcastReceiver
wifiManager.startScan();
}
protected void onPause() {
unregisterReceiver(wifiReciever);
super.onPause();
}
protected void onResume() {
registerReceiver(wifiReciever, new IntentFilter(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION));
super.onResume();
}
class WifiScanReceiver extends BroadcastReceiver {
public void onReceive(Context c, Intent intent) {
List<ScanResult> wifiScanList = wifiManager.getScanResults();
ssidList.clear(); // clear to make sure we do not get duplicated entries
for (int i = 0; i < wifiScanList.size(); i++) {
String ssid = wifiScanList.get(i).SSID; //Get the SSID
ssidList.add(ssid); //add SSID to the list
Log.d("SSID", ssid);
}
//You can call this to keep scaning if you need to, or you can set up a Timer to scan every X seconds
//wifiManager.startScan();
}
}
}
每次onReceive
运行时,您都会看到所有可用的SSID列表,这些SSID将保存在ssidList
中。
答案 1 :(得分:0)
试试这个answer。
public class WiFiDemo extends Activity implements 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.main);
textStatus = (TextView) findViewById(R.id.textStatus);
buttonScan = (Button) findViewById(R.id.buttonScan);
buttonScan.setOnClickListener(this);
lv = (ListView)findViewById(R.id.list);
wifi = (WifiManager) 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)
{ }
}
}