So halten Sie Daten in Aktivität aus der Datenbank

Question

Ich habe diese App, wo ich Sende Absicht von Log In Activity und Empfangen von Absicht für Benutzeraktivität (siehe Anhang), aber wenn ich von anderen Seiten navigieren und dann zu meinem UserActivity dh; Home, Contact Us es ergibt "Nullwerte", ich möchte die Daten in User Activity behalten, auch wenn ich von anderen Seiten navigiere. Hilfe bitte. Vielen Dank!

Successful store

Null values

Hier ist meine Codes ..

public class LoginActivityEN AppCompatActivity erstreckt {

private static final String TAG = "LoginActivity"; 
private static final String URL_FOR_LOGIN = "http://192.168.13.40/android_login_example/login.php"; 
ProgressDialog progressDialog; 
private EditText loginInputUsername, loginInputPassword; 
Button btnlogin; 
Button btnLinkSignup; 


// Session Manager Class 
SessionManager session; 

//Storing Sessions 
SharedPreferences sharedPreferences; 


@Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     overridePendingTransition(R.anim.fadein, R.anim.fadeout); 
     setContentView(R.layout.activity_login_en); 




    // Session Manager 
    session = new SessionManager(getApplicationContext()); 
    sharedPreferences = getSharedPreferences("my_prefs", MODE_PRIVATE); 
    SharedPreferences.Editor editor = sharedPreferences.edit(); 
    editor.putString("user_id", "password"); 


    //Bottom Navigation 
    BottomNavigationView bottomNavigationView = (BottomNavigationView) findViewById(R.id.bottomNavView_Bar); 
     BottomNavigationViewHelper.disableShiftMode(bottomNavigationView); 
     Menu menu = bottomNavigationView.getMenu(); 
     MenuItem menuItem = menu.getItem(1); 
     menuItem.setChecked(true); 

     bottomNavigationView.setOnNavigationItemSelectedListener(new BottomNavigationView.OnNavigationItemSelectedListener() { 
      @Override 
      public boolean onNavigationItemSelected(@NonNull MenuItem item) { 
       switch (item.getItemId()){ 

        case R.id.navigation_home: 
         Intent intent1 = new Intent(LoginActivityEN.this, Home.class); 
         startActivity(intent1); 
         break; 

        case R.id.navigation_card: 



         break; 

        case R.id.navigation_price: 
         Intent intent3 = new Intent(LoginActivityEN.this, PriceActivity.class); 
         startActivity(intent3); 
         break; 
        case R.id.navigation_more: 
         Intent intent4 = new Intent(LoginActivityEN.this, More.class); 
         startActivity(intent4); 
       } 
       return false; 
      } 
     }); 


     //Login Activity 
     loginInputUsername = (EditText) findViewById(R.id.login_input_username); 
     loginInputPassword = (EditText) findViewById(R.id.login_input_password); 
     btnlogin = (Button) findViewById(R.id.btn_login); 
     btnLinkSignup = (Button) findViewById(R.id.registerbutton); 
     // Progress dialog 
     progressDialog = new ProgressDialog(this); 
     progressDialog.setCancelable(false); 

     btnlogin.setOnClickListener(new View.OnClickListener() { 
      @Override 
      public void onClick(View view) { 
       loginUser(loginInputUsername.getText().toString(), 
         loginInputPassword.getText().toString()); 

      } 
     }); 
     //Register 
     btnLinkSignup.setOnClickListener(new View.OnClickListener() { 
      @Override 
      public void onClick(View view) { 
       Intent i = new Intent(getApplicationContext(), RegisterEN.class); 
       startActivity(i); 
      } 
     }); 
    } 

private void loginUser(final String username, final String password) { 


    // Tag used to cancel the request 
    String cancel_req_tag = "login"; 
    progressDialog.setMessage("Logging you in..."); 
    showDialog(); 
    StringRequest strReq = new StringRequest(Request.Method.POST, 
      URL_FOR_LOGIN, new Response.Listener<String>() { 

     @Override 
     public void onResponse(String response) { 
      Log.d(TAG, "Register Response: " + response.toString()); 
      hideDialog(); 
      try { 
       JSONObject jObj = new JSONObject(response); 
       boolean error = jObj.getBoolean("error"); 

       if (!error) { 
        String user = jObj.getJSONObject("user").getString("customers_firstname"); 
        String user1 = jObj.getJSONObject("user").getString("customers_lastname"); 
        String user2 = jObj.getJSONObject("user").getString("reward_points"); 
        String user3 = jObj.getJSONObject("user").getString("NoShares"); 
        String user4 = jObj.getJSONObject("user").getString("CardType_ID"); 
        String user5 = jObj.getJSONObject("user").getString("Card_No"); 
        // Launch User activity 
        Intent intent = new Intent(LoginActivityEN.this, UserActivity.class); 
        intent.putExtra("customers_firstname", user); 
        intent.putExtra("customers_lastname", user1); 
        intent.putExtra("reward_points", user2); 
        intent.putExtra("NoShares", user3); 
        intent.putExtra("CardType_ID", user4); 
        intent.putExtra("Card_No", user5); 
        startActivity(intent); 
        finish(); 

        if(username.trim().length() > 0 && password.trim().length() > 0){ 
         session.createLoginSession("username", "password"); 
         Toast.makeText(getApplicationContext(), "Session Active", Toast.LENGTH_SHORT).show(); 

        } 

       } else { 

        String errorMsg = jObj.getString("error_msg"); 
        Toast.makeText(getApplicationContext(), 
          errorMsg, Toast.LENGTH_SHORT).show(); 
       } 
      } catch (JSONException e) { 
       e.printStackTrace(); 
      } 

     } 
    }, new Response.ErrorListener() { 

     @Override 
     public void onErrorResponse(VolleyError error) { 
      Log.e(TAG, "Login Error: " + error.getMessage()); 
      Toast.makeText(getApplicationContext(), 
        error.getMessage(), Toast.LENGTH_SHORT).show(); 
      hideDialog(); 
     } 
    }) { 

     @Override 
     protected Map<String, String> getParams() { 
      // Posting params to login url 
      Map<String, String> params = new HashMap<String, String>(); 
      params.put("username", username); 
      params.put("customers_password", password); 
      return params; 
     } 

    }; 
    // Adding request to request queue 
    AppSingleton.getInstance(getApplicationContext()).addToRequestQueue(strReq,cancel_req_tag); 
} 

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

UserActivity.java

public class UserActivity AppCompatActivity erstreckt {

private TextView greetingTextView; 
private TextView totpoints; 
private TextView totshare; 
private Button btnLogOut; 
private ImageView cardshow; 
private ImageView bmbc; 
private TextView bmbc_text; 

SharedPreferences sharedPreferences; 


// Session Manager Class 
SessionManager session; 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    overridePendingTransition(R.anim.fadein, R.anim.fadeout); 
    setContentView(R.layout.activity_user); 



    // Session class instance 
    session = new SessionManager(getApplicationContext()); 



    BottomNavigationView bottomNavigationView = (BottomNavigationView) findViewById(R.id.bottomNavView_Bar); 
    BottomNavigationViewHelper.disableShiftMode(bottomNavigationView); 
    Menu menu = bottomNavigationView.getMenu(); 
    MenuItem menuItem = menu.getItem(1); 
    menuItem.setChecked(true); 

    bottomNavigationView.setOnNavigationItemSelectedListener(new BottomNavigationView.OnNavigationItemSelectedListener() { 
     @Override 
     public boolean onNavigationItemSelected(@NonNull MenuItem item) { 
      switch (item.getItemId()) { 

       case R.id.navigation_home: 
        Intent intent1 = new Intent(UserActivity.this, Home.class); 
        startActivity(intent1); 
        break; 

       case R.id.navigation_card: 

        break; 

       case R.id.navigation_price: 
        Intent intent3 = new Intent(UserActivity.this, PriceActivity.class); 
        startActivity(intent3); 
        break; 

       case R.id.navigation_more: 
        Intent intent4 = new Intent(UserActivity.this, PriceActivity.class); 
        startActivity(intent4); 
        break; 
      } 


      return false; 
     } 


    }); 



    greetingTextView = (TextView) findViewById(R.id.greeting_text_view); 
    totpoints = (TextView) findViewById(R.id.au_tpresult); 
    totshare = (TextView) findViewById(R.id.au_tsresult); 
    btnLogOut = (Button) findViewById(R.id.logout_button); 
    cardshow = (ImageView) findViewById(R.id.card_stack); 



    Intent intent = getIntent(); 
    String user = intent.getStringExtra("customers_firstname"); 
    String user1 = intent.getStringExtra("customers_lastname"); 
    String user2 = intent.getStringExtra("reward_points"); 
    String user3 = intent.getStringExtra("NoShares"); 
    String user4 = intent.getStringExtra("CardType_ID"); 
    String user5 = intent.getStringExtra("Card_No"); 


    greetingTextView.setText(user + " " + user1); 
    totpoints.setText(user2); 
    totshare.setText(user3); 


    if (user4 == (null)) { 
     ((ImageView) findViewById(R.id.card_stack)).setImageResource(R.color.transparent); 
    } else if (user4.equals("0")) { 
     ((ImageView) findViewById(R.id.card_stack)).setImageResource(R.drawable.thar_silver); 
    } else if (user4.equals("1")) { 
     ((ImageView) findViewById(R.id.card_stack)).setImageResource(R.drawable.thar_gold); 

    } 

    // Progress dialog 
    btnLogOut.setOnClickListener(new View.OnClickListener() { 
     @Override 
     public void onClick(View view) { 

      session.logoutUser(); 
      Toast.makeText(getApplicationContext(), "Session Ended", Toast.LENGTH_SHORT).show(); 
      Intent i = new Intent(getApplicationContext(), LoginActivityEN.class); 
      startActivity(i); 
     } 
    }); 

    session.checkLogin(); 

    //CARD NUMB 

Answer 1

Es gibt viele Ansätze, die Sie nutzen könnten.

1. Persistance Speicher (Long Duration, auch nach App schließt): a. Verwenden Sie SharedPreferences, b. SQLite

2. anderer Weg ist .to die Anwendungsklasse zu erweitern und es in einer Variablen zu speichern, bleibt es bis zum App geschlossen ist. (Short Duration, Während eine App-Sitzung und Schließen des App)

Ihr Ansatz hängt von der Lebensdauer Ihrer Daten