Question

我将广播接收器定义为内部类。我不想从接收器到外部类获取对象，如下所示：

class External {
public object ;
class Inner {
object = something ;
getObject () { return object; }
}//end Inner class
method (){
Inner inn = new Inner();
inn.getObject(); //here i would like to get the object from inner class
}
}

但它为我做了工作，我得到一个空的对象，这是我的真实代码：

public class Wifi extends Activity implements OnClickListener{
/** Called when the activity is first created. */
WifiManager wifi;
Button      enab;
String resultsString ; 
String[] myStringArray;

public class Receiver extends BroadcastReceiver{

    @Override
    public void onReceive(Context context, Intent intent) {
        if(intent.getAction().equals(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION)){
            List<ScanResult> results = wifi.getScanResults();

            resultsString = results.toString() ;

            //Log.i("resultsString",resultsString);
            List<WifiConfiguration> resultsConf = wifi.getConfiguredNetworks();                 
        }
    }
            /*****  I would like to get resultsString *******/
    public String getResult(){
        return resultsString ;
    }
}

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_wifi);
    ConnectivityManager cxMgr = (ConnectivityManager)getSystemService(Context.CONNECTIVITY_SERVICE);
    wifi = (WifiManager)getSystemService(Context.WIFI_SERVICE);

    Receiver receiver = new Receiver();
    /***** I would like to get resultsString in this method but I'm getting a null  **/

    registerReceiver(receiver,new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION));
    registerReceiver(receiver,new IntentFilter(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION));
Log.i("receiver.getResult()",receiver.getResult()+"");  
}
}

这是我的logCat

03-27 12:28:51.947: I/receiver.getResult()(24524): null

谢谢。我有人会帮助我:)。

Answer 1

试试这个..

我猜您在下面的行中遇到错误

Log.i("receiver.getResult()",receiver.getResult());

可能接收器 null ，以便您可以像下面一样检查添加""+

Log.i("receiver.getResult()",""+receiver.getResult());

修改

IntentFilter intentFilter =new IntentFilter(Receiver.ACTION_TEXT_CAPITALIZED); intentFilter.addCategory(Intent.CATEGORY_DEFAULT); /* create new broadcast receiver*/ Receiver receiver = new Receiver(); registerReceiver(receiver, intentFilter);

在Receiver类中添加

public final static String ACTION_TEXT_CAPITALIZED= "com.android.guide.exampleintentservice.intent.action.ACTION_TEXT_CAPITALIZED";

您可以发送以下信息

Intent resultBroadCastIntent =new Intent(); resultBroadCastIntent.setAction(Receiver.ACTION_TEXT_CAPITALIZED); resultBroadCastIntent.setAction(ConnectivityManager.CONNECTIVITY_ACTION); resultBroadCastIntent.setAction(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION); resultBroadCastIntent.addCategory(Intent.CATEGORY_DEFAULT); sendBroadcast(resultBroadCastIntent);

Android：从内部类中获取对象

1 个答案: