Android 扫描WiFi

public class MainActivity extends AppCompatActivity {

    String Tag = "MainActivity";
    final int PERMISSION_REQUEST_CODE = 1;
    String [] permission = new String[]{Manifest.permission.ACCESS_FINE_LOCATION};
    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.main);
        if (Build.VERSION.SDK_INT>Build.VERSION_CODES.O){
            if (!hasPermissionsGranted(permission)) {
                ActivityCompat.requestPermissions(this,permission , PERMISSION_REQUEST_CODE);
            }
        }

        WifiManager wifiManager = getSystemService(WifiManager.class);
        boolean b = wifiManager.startScan();
        Log.e("longjiang", "wifiManager.startScan " + b);
        for (ScanResult scanResult : wifiManager.getScanResults()) {
            Log.e("longjiang", scanResult.toString());
        }

    }
    public boolean hasPermissionsGranted(@NonNull String[] permissions) {
        for (String permission : permissions) {
            if (ActivityCompat.checkSelfPermission(this, permission)
                    != PackageManager.PERMISSION_GRANTED) {
                return false;
                //此时没有授权，返回false
            }
        }
        return true;
        //已经授权过，返回true
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {

        Log.d(Tag,"-------onRequestPermissionsResult--------");
        if (requestCode == PERMISSION_REQUEST_CODE) {
            if (!hasPermissionsGranted(permissions)) {//返回false代表申请失败
                Toast.makeText(this, "授权失败", Toast.LENGTH_SHORT).show();
                this.finish();
            }else {
                Toast.makeText(this, "授权成功", Toast.LENGTH_SHORT).show();
            }
        } else {
            super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        }
    }
}

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