首页 > 解决方案 > Android登录并获取json数组

问题描述

我制作了使用 volley 从 api 获取 json 数组的应用程序,json 数组将在登录成功时显示。

这是我的 json 回复。

"status": "success",
"tampil": [
    {
        "serial": "f9fa46a266d5b086053f2a8d3c850805",
        "sales_order_no_car": "SONH-19/0009666",
        "sales_order_no_materials": null,
        "sales_order_no_building": null,
        "order_date": "2019-02-13 00:00:00",
        "urgent_status": null,
        "note2": null,
        "installation_address": "HONDA CAKRA RADEN INTEN",
        "car_model": "HRV 2017",
        "full_name": null,
        "name_showroom": "PT. PANGUKIRGADING CAKRAUTAMA",
        "window_film_desc": "V-KOOL VRX60,V-KOOL BX15,V-KOOL BX05,V-KOOL BX05",
        "chassis_no": "MHRRU1850JJ804432",
        "installation_type": "01",
        "sales_type": "1",
        "user_serial": "4cd6110cba8b30c4960ca1108f1ffba4"
    },
    {
        "serial": "ccde84a114bed8401f97a8056b2b5db2",
        "sales_order_no_car": "SONH-19/0009667",
        "sales_order_no_materials": null,
        "sales_order_no_building": null,
        "order_date": "2019-02-13 00:00:00",
        "urgent_status": null,
        "note2": null,
        "installation_address": "HONDA CAKRA RADEN INTEN",
        "car_model": "HRV 2017",
        "full_name": null,
        "name_showroom": "PT. PANGUKIRGADING CAKRAUTAMA",
        "window_film_desc": "V-KOOL VRX60,V-KOOL BX15,V-KOOL BX15",
        "chassis_no": "MHRRU1860KJ800100",
        "installation_type": "01",
        "sales_type": "1",
        "user_serial": "4cd6110cba8b30c4960ca1108f1ffba4"
    },
    {
        "serial": "ca07913d6e4f2b28fc4dff47f4673727",
        "sales_order_no_car": "SONH-19/0009668",
        "sales_order_no_materials": null,
        "sales_order_no_building": null,
        "order_date": "2019-02-13 00:00:00",
        "urgent_status": null,
        "note2": null,
        "installation_address": "HONDA CAKRA RADEN INTEN",
        "car_model": "NEW CRV 2017",
        "full_name": null,
        "name_showroom": "PT. PANGUKIRGADING CAKRAUTAMA",
        "window_film_desc": "V-KOOL VRX60,V-KOOL BX05,V-KOOL BX05",
        "chassis_no": "MHRRW1880JJ811140",
        "installation_type": "01",
        "sales_type": "1",
        "user_serial": "4cd6110cba8b30c4960ca1108f1ffba4"
    },
    {
        "serial": "0d17e67eb5deb6d69ab6ea08004f7fd1",
        "sales_order_no_car": "SONH-19/0009669",
        "sales_order_no_materials": null,
        "sales_order_no_building": null,
        "order_date": "2019-02-13 00:00:00",
        "urgent_status": null,
        "note2": null,
        "installation_address": "HONDA CAKRA RADEN INTEN",
        "car_model": "NEW CRV 2017",
        "full_name": null,
        "name_showroom": "PT. PANGUKIRGADING CAKRAUTAMA",
        "window_film_desc": "V-KOOL VRX15,V-KOOL BX15,V-KOOL BX05,V-KOOL BX15",
        "chassis_no": "MHRRW1880JJ808477",
        "installation_type": "01",
        "sales_type": "1",
        "user_serial": "4cd6110cba8b30c4960ca1108f1ffba4"
    },
    {
        "serial": "85917eb065b0143e93b92e24b9d5175a",
        "sales_order_no_car": "SOPKK-19/0001246",
        "sales_order_no_materials": null,
        "sales_order_no_building": null,
        "order_date": "2019-02-12 00:00:00",
        "urgent_status": "2",
        "note2": null,
        "installation_address": "CENTRAL 88 BP VETER - 081282600328",
        "car_model": "NEW CRV 2017",
        "full_name": null,
        "name_showroom": "PT. MAJU MOBILINDO",
        "window_film_desc": "V-KOOL VRX-60, V-KOOL BX15",
        "chassis_no": "MHRRW3830HJ800733",
        "installation_type": "05",
        "sales_type": "7",
        "user_serial": "4cd6110cba8b30c4960ca1108f1ffba4"
    },
    {
        "serial": "4e7b7ae6aaad80388c6628bc2c72a7fa",
        "sales_order_no_car": "SOPKK-18/0001122",
        "sales_order_no_materials": null,
        "sales_order_no_building": null,
        "order_date": "2018-11-16 00:00:00",
        "urgent_status": "2",
        "note2": null,
        "installation_address": "GUDANG SUNTER",
        "car_model": "NEW ACCORD 2017",
        "full_name": null,
        "name_showroom": "PT. IMORA MOTOR",
        "window_film_desc": "V-KOOL BX15",
        "chassis_no": "MRHCR2640JP810152",
        "installation_type": "31",
        "sales_type": "7",
        "user_serial": "4cd6110cba8b30c4960ca1108f1ffba4"
    },
    {
        "serial": "96b1bceb2bcd7bc78ebda91f833b2671",
        "sales_order_no_car": "SOLKL-18/0000019",
        "sales_order_no_materials": null,
        "sales_order_no_building": null,
        "order_date": "2018-03-20 00:00:00",
        "urgent_status": "2",
        "note2": null,
        "installation_address": "JL. JATI 1 NO.8 RT.002/006 SUNGAI BAMBU, T. PRIOK ( PASAR PELITA JAYA/ PASAR POOL YANG BARU) (KLP GADING)",
        "car_model": "ALL NEW AVANZA",
        "full_name": "MASIDEH",
        "name_showroom": "ASTRA INTERNASIONAL TOYOTA SALES OPERATION-SUNTER",
        "window_film_desc": "V-KOOL 70",
        "chassis_no": "MHKM1CA4JEK083149",
        "installation_type": "08",
        "sales_type": "7",
        "user_serial": "4cd6110cba8b30c4960ca1108f1ffba4"
    },
    {
        "serial": "e494c4b7ec7dcedb4c0d54b3a6c9c85c",
        "sales_order_no_car": "SOCH-18/0137485",
        "sales_order_no_materials": null,
        "sales_order_no_building": null,
        "order_date": "2018-02-22 00:00:00",
        "urgent_status": "2",
        "note2": null,
        "installation_address": "CILINCING DOSH-18/0000166",
        "car_model": "HRV 2017",
        "full_name": null,
        "name_showroom": "HONDA MITRA JAYAPURA",
        "window_film_desc": "V-KOOL VRX60, V-KOOL BX15",
        "chassis_no": "MHRRU1730JJ700410",
        "installation_type": "01",
        "sales_type": "1",
        "user_serial": "4cd6110cba8b30c4960ca1108f1ffba4"
    }
  ]
}

这是我的登录代码

public class LoginFragment extends Fragment {

public static final String TAG = LoginFragment.class.getSimpleName();
private EditText etEmail, etPass;
private Button btnLogin;
Context context;
ProgressDialog progressDialog;
SharedPrefManager sharedPrefManager;
private VolleyController mInstance;

public LoginFragment() {
    // Required empty public constructor
}


@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment
    View v = inflater.inflate(R.layout.fragment_login, container, false);

    context = getActivity();
    etEmail = v.findViewById(R.id.et_email);
    etPass = v.findViewById(R.id.et_pass);
    btnLogin = v.findViewById(R.id.btn_login);
    progressDialog = new ProgressDialog(getActivity());
    sharedPrefManager = new SharedPrefManager(getActivity());

    btnLogin.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
          LoginProcess();
        }
    });


  return v;
}


private void LoginProcess() {
    final String email = etEmail.getText().toString().trim();
    final String pass = etPass.getText().toString().trim();
    progressDialog.setMessage("Login process...");
    showDialog();



    StringRequest stringRequest = new StringRequest(Request.Method.POST, ModelVar.url,
            new Response.Listener<String>() {
        @Override
        public void onResponse(String response) {
            JSONObject jobj = null;
            try{
                jobj = new JSONObject(response.toString());
            }catch (JSONException e){
                e.printStackTrace();
            }

            String status = null;
            try{
                status = jobj.getString("status");
            }catch (JSONException e){
                e.printStackTrace();
            }

            if(status.contains("success")){
                Toast.makeText(context, "SUCCESS LOGIN",Toast.LENGTH_LONG).show();


                sharedPrefManager.saveSPBoolean(SharedPrefManager.LOGGED_IN ,true);


                hideDialog();


                gotoMenuFragment();

            }else{
                hideDialog();
                Toast.makeText(context, "Invalid username or password", Toast.LENGTH_LONG).show();
            }
        }
    }, new Response.ErrorListener(){

        @Override
        public void onErrorResponse(VolleyError error) {
          hideDialog();
            Toast.makeText(context, "The Server Unreachable", Toast.LENGTH_LONG).show();
        }
    }){
        protected Map<String , String > getParams() throws AuthFailureError {
            Map<String,String> params = new HashMap<>();

            params.put(ModelVar.KEY_USER_ID, email);
            params.put(ModelVar.KEY_PASSWORD, pass);

                    return params;
        }
    };

    Volley.newRequestQueue(getActivity()).add(stringRequest);
}



private void gotoMenuFragment() {


    FragmentTransaction ft = getFragmentManager().beginTransaction();
    ft.replace(R.id.fragment_container, new MenuFragment(), "Menu");
    ft.commit();
    ft.addToBackStack(null);
}


private void showDialog() {
    if (!progressDialog.isShowing())
        progressDialog.show();
}

private void hideDialog() {
    if (progressDialog.isShowing())
        progressDialog.dismiss();
  }
}

这是我的menufragment代码。我不知道我怎么能jsonarraymenufragment

public class MenuFragment extends Fragment implements SwipeRefreshLayout.OnRefreshListener {

public static final String TAG = MenuFragment.class.getSimpleName();
ListView lvMenu;
AdapterData adapterData;
List<Data> listdata;
VolleyController volleyController;
SwipeRefreshLayout swipeRefreshLayout;

onLogoutListener logoutListener;



public interface onLogoutListener{
    public void logoutPerformed();
}

public MenuFragment() {
    // Required empty public constructor
}


@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    Button btnLogout;

    // Inflate the layout for this fragment
    View v= inflater.inflate(R.layout.fragment_menu, container, false);

    btnLogout = v.findViewById(R.id.btn_logout);

    btnLogout.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            logoutListener.logoutPerformed();
        }
    });
        lvMenu = v.findViewById(R.id.lv_menu);
        adapterData = new AdapterData(getActivity(), listdata);
        lvMenu.setAdapter(adapterData);
        swipeRefreshLayout = v.findViewById(R.id.srl_menu);

    swipeRefreshLayout.setOnRefreshListener(this);

    return v;
}



    private void getUserData() {
    listdata.clear();
    swipeRefreshLayout.setRefreshing(true);
    adapterData.notifyDataSetChanged();

    final JsonArrayRequest jsonArrayRequest = new JsonArrayRequest(ModelVar.url,
              new Response.Listener<JSONArray>() {
        @Override
        public void onResponse(JSONArray response) {
            JSONObject jobj = null;
            try {
                jobj = new JSONObject(response.toString());
            } catch (JSONException e) {
                e.printStackTrace();
            }

            JSONArray obj = null;
            try {
                obj = jobj.getJSONArray("tampil");
            } catch (JSONException e) {
                e.printStackTrace();
            }

            Log.d(TAG, response.toString());


            for (int i = 0; i < obj.length(); i++) {
                try {

                    JSONObject jdata = obj.getJSONObject(i);

                    //here u can get all field like this
                    Data item = new Data();

                    String sonc = jdata.getString("sales_order_no_car");
                    String address = jdata.getString("installation_address");
                    String nameShowroom = jdata.getString("name_showroom");
                    String orderDate = jdata.getString("order_date");

                    item.setSales_order_no_car(sonc);
                    item.setInstallation_address(address);
                    item.setName_showroom(nameShowroom);
                    item.setOrder_date(orderDate);

                    listdata.add(item);

                } catch (JSONException e) {
                    e.printStackTrace();
                }
            }



            adapterData.notifyDataSetChanged();

            swipeRefreshLayout.setRefreshing(false);
        }
    }, new Response.ErrorListener() {

        @Override
        public void onErrorResponse(VolleyError error) {
            VolleyLog.d(TAG, "Error: " + error.getMessage());
            swipeRefreshLayout.setRefreshing(false);
        }
    });


    VolleyController.getInstance(getActivity()).addToRequestQueue(jsonArrayRequest);
}



    @Override
    public void onRefresh() {
        listdata.clear();
        adapterData.notifyDataSetChanged();
        getUserData();

}

@Override
public void onAttach(Context context) {
    super.onAttach(context);
    Activity activity = (Activity) context;
    logoutListener = (onLogoutListener) activity;
  }

}

我的项目出错了

E/AndroidRuntime:致命异常:主进程:com.scsvkool.autosendemail,PID:7047 java.lang.RuntimeException:无法启动活动 ComponentInfo{com.scsvkool.autosendemail/com.scsvkool.autosendemail.MainActivity}:java.lang。 NullPointerException:尝试在 android.app.ActivityThread.handleLaunchActivity(ActivityThread. java:2476) 在 android.app.ActivityThread.-wrap11(ActivityThread.java) 在 android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344) 在 android.os.Handler.dispatchMessage(Handler.java:102)在 android.app.ActivityThread 的 android.os.Looper.loop(Looper.java:148)。main(ActivityThread.java:5417) 在 java.lang.reflect.Method.invoke(Native Method) 在 com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726) 在 com.android.internal。 os.ZygoteInit.main(ZygoteInit.java:616)

引起:java.lang.NullPointerException:尝试在 com.scsvkool.autosendemail.DataModel.AdapterData.getCount(AdapterData.java:34) 的空对象引用上调用接口方法“int java.util.List.size()”在 android.widget.ListView.setAdapter(ListView.java:491) 在 com.scsvkool.autosendemail.FragmentActivity.MenuFragment.onCreateView(MenuFragment.java:74) 在 android.support.v4.app.Fragment.performCreateView(Fragment.java :2439) 在 android.support.v4.app.FragmentManagerImpl.moveFragmentToExpectedState(FragmentManager.java:1784) 在 android.support.v4.app 的 android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1460)。 FragmentManagerImpl.moveToState(FragmentManager.java:1852) 在 android.support.v4.app.BackStackRecord。executeOps(BackStackRecord.java:802) 在 android.support.v4.app.FragmentManagerImpl.executeOps(FragmentManager.java:2625) 在 android.support.v4.app.FragmentManagerImpl.executeOpsTogether(FragmentManager.java:2411) 在 android.support .v4.app.FragmentManagerImpl.removeRedundantOperationsAndExecute(FragmentManager.java:2366) 在 android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:2273) 在 android.support.v4.app.FragmentManagerImpl.dispatchStateChange(FragmentManager.java :3273) 在 android.support.v4.app.FragmentManagerImpl.dispatchActivityCreated(FragmentManager.java:3229) 在 android.support.v4.app.FragmentController.dispatchActivityCreated(FragmentController.java:201) 在 android.support.v4.app。 FragmentActivity.onStart(FragmentActivity.java:620) 在 android.support.v7.app.AppCompatActivity.onStart(AppCompatActivity.java:178) 在 android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1237) 在 android.app.Activity.performStart(Activity.java:6253 )在 android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2379) 在 android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476) 在 android.app.ActivityThread.-wrap11(ActivityThread.java) 在 android.app。 ActivityThread$H.handleMessage(ActivityThread.java:1344) at android.os.Handler.dispatchMessage(Handler.java:102) at android.os.Looper.loop(Looper.java:148) at android.app.ActivityThread.main (ActivityThread.java:5417) 在 com.android 的 java.lang.reflect.Method.invoke(Native Method)。internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726) 在 com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)

标签: androidjsonandroid-volley

解决方案


您在适配器上提供空列表

adapterData = new AdapterData(getActivity(), listdata);

在发送到适配器之前用 new 初始化“listdata”,比如

listdata = new ArrayList<Data>;

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