Question

首先我提示用户打开wifi。我想打开wifi，如果关闭，扫描所有可用的无线网络，并根据它的ssid连接到某个。我想注册一个广播接收器，等到WifiManager完成扫描结果。

     public class Project1 extends Activity {

        /**
         * Called when the activity is first created.
         */
        EditText userName;
        EditText passWord;
        Button button;
        TextView thankYou;
        WifiManager wifiManager;
        List<ScanResult> results1;
        BroadcastReceiver receiver;
    public Boolean connectToNetworK() {
            Log.e("Start of connect","Debug");
            Log.e("before wifi manager of connect","Debug");
            if(!wifiManager.isWifiEnabled()){
                Log.e("wifi is not enabled","Debug");
                wifiManager.setWifiEnabled(true);
            }

            Log.e("after wifi manager of connect","Debug");
            List<ScanResult>results =null; 
            Log.e("after scan result = null","Debug");
            while(!wifiManager.isWifiEnabled())
            {
                Log.e("wifi still off","Debug");
            }
            Log.e("wifi is on","Debug");
            Log.e("starting scan","Debug");
            wifiManager.startScan();


            Log.e("waiting","Debug");
            if(results1!=null && !results1.isEmpty())
            {
                Log.e("Results1 is not emplty","Debug");
            }
    }
    @Override
        public void onStop()
        {
            unregisterReceiver(receiver);
        }
    public void onCreate(Bundle savedInstanceState) {
            final Context contex = this;
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);
            wifiManager = (WifiManager) getSystemService(Context.WIFI_SERVICE);
    if(receiver == null){
                Log.e("Registering reciver","mark");
                receiver = new BroadcastReceiver(){
                    @Override
                    public void onReceive(Context context, Intent intent){
                        Log.e("In broad cast reciver","mark");
                        results1 =wifiManager.getScanResults();
                    }
                };
                registerReceiver(receiver, new IntentFilter(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION));

            }
    }
if (!mWifi.isConnected()) {
AlertDialog.Builder alert = new AlertDialog.Builder(this);
            alert.setTitle("Please Open the Wifi");
            alert.setMessage("Your Wifi is Currently Turned off, Would You like to turn it on?");
            alert.setPositiveButton("Ok", new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int which) {
                    //WifiManager wifi = (WifiManager) getSystemService(Context.WIFI_SERVICE);
                    if(connectToMobinilNetworK())
                    {
                        AfterWifiIsOn();
                    }
                    else{
                        Intent intent = new Intent(contex, ErrorPage.class);
                        startActivity(intent);}
                }
            });
            alert.setNegativeButton("No", new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int which) {
                    Intent intent = new Intent(contex, ErrorPage.class);
                    startActivity(intent);
                }
            });
            alert.show();
        }    }
}
    }
The list of scan resutls are always empty and the logs inside the broadcast receiver is not written.
Thanks in advance.

Answer 1

您是否在AndroidManifest中设置了正确的权限？根据{{3}}，您的权限应如下所示：

<uses-sdk android:minSdkVersion="14" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />
<uses-permission android:name="android.permission.CHANGE_NETWORK_STATE" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

广播接收器不工作

1 个答案: