Question

我正在从Google商家信息中检索我的JSON响应，并且我想在ListView中的另一个Acivity中显示它。我想要做的是将Object从一个活动传递到另一个活动，但它似乎不起作用。

这是我的活动的一部分，我试图传递JSON：

public class GetNearbyPlacesList extends AsyncTask<Object, String, String> {

    String googlePlacesData;
    String url;
    List<HashMap<String, String>> nearbyPlacesList = null;
    private Intent context;
    private SharedPreferences.Editor intent;

    @Override
    protected String doInBackground(Object... params) {
        try {
            Log.d("GetNearbyPlacesData", "doInBackground entered");
            url = (String) params[0];
            DownloadUrl downloadUrl = new DownloadUrl();
            googlePlacesData = downloadUrl.readUrl(url);
            Log.d("GooglePlaceData", googlePlacesData);
            Log.d("GooglePlacesReadTask", "doInBackground Exit");
        } catch (Exception e) {
            Log.d("GooglePlacesReadTask", e.toString());
        }
        return googlePlacesData;
    }

protected void onPostExecute(String result) {
                Log.d("GooglePlacesReadTask", "onPostExecute Entered");
                ListParser listParser = new ListParser();
                nearbyPlacesList = listParser.parse(result);
                Log.d("List of restaurants", nearbyPlacesList.toString());
                Log.d("GooglePlacesReadTask", "onPostExecute Exit");
        Intent intent = new Intent(GetNearbyPlacesList.this,ListRestActivity.class);
        intent.putExtra("deal", nearbyPlacesList.toString());
        startActivity(intent);
    }

这是我想将JSON传递给的类：

   public class ListRestActivity extends Activity implements
            GoogleApiClient.ConnectionCallbacks,
    GoogleApiClient.OnConnectionFailedListener,
    LocationListener  {


ListView lv;
double latitude;
double longitude;
private int PROXIMITY_RADIUS = 10000;
GoogleApiClient mGoogleApiClient;
Location mLastLocation;
Marker mCurrLocationMarker;
LocationRequest mLocationRequest;
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_listrest);
    if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
        checkLocationPermission();
    }

    //Check if Google Play Services Available or not
    if (!CheckGooglePlayServices()) {
        Log.d("onCreate", "Finishing test case since Google Play Services are not available");
        finish();
    }
    else {
        Log.d("onCreate","Google Play Services available.");
    }

    String Restaurant = "restaurant";

    String url = getUrl(latitude, longitude, Restaurant);
    Object[] DataTransfer = new Object[1];
    DataTransfer[0] = url;
    GetNearbyPlacesList getNearbyPlacesList = new GetNearbyPlacesList();
    getNearbyPlacesList.execute(DataTransfer);
}

Answer 1

在第二个活动中，您可以使用

访问意图的JSON字符串

getIntent().getStringExtra("deal");

然后，如果需要，您可以将其转换回JSON对象。

<强>更新

您在Async任务中的Intent构造函数中收到错误的原因是您没有将有效的上下文作为参数传递。你的上下文属性是Intent类型，它应该是Context，所以修复如下：

private Context mContext;

将构造函数添加到GetNearbyPlacesList中，如此

public GetNearbyPlacesList(Context context) {
    mContext = context
}

在实例化时传递一个上下文，这是您最有可能的第一个活动。

那么当您在异步任务类中构造该意图时，您可以这样做：

Intent intent = new Intent(mContext, ListRestActivity.class)

将JSON对象从一个活动传递到另一个Android

1 个答案: