当我尝试使用正确的凭据登录时，应用程序意外停止

Question

我只是安卓编码的新手。我只下载了这段代码并进行了一些更改。当我尝试运行应用程序并输入错误的凭据时，它工作正常。但是当我输入正确的凭据时，应用程序将自动关闭。我尽力修复错误，但我失败了。希望你能帮助我，并指导我如何解决此错误。

登录.java

try {
                JSONObject jObj = new JSONObject(response);
                boolean error = jObj.getBoolean("error");
                // Check for error node in json
                if (!error) {
                    // user successfully logged in
                    // Create login session
                    session.setLogin(true);
                    // Now store the user in SQLite
                    //String uid = jObj.getString("uid");
                    JSONObject user = jObj.getJSONObject("user");
                    String br_code = user.getString("br_code");
                    String mem_id = user.getString("mem_id");
                    String username = user.getString("username");
                    String email = user.getString("email");
                    String created_at = user.getString("created_at");
                    // Inserting row in users table
                    db.addUser(br_code, mem_id, username, email, created_at);
                    // Launch main activity
                    Intent intent = new Intent(LoginActivity.this,
                            MainActivity.class);
                    startActivity(intent);
                    finish();
                } else {
                    // Error in login. Get the error message
                    String errorMsg = jObj.getString("error_msg");
                    Toast.makeText(getApplicationContext(),
                            errorMsg, Toast.LENGTH_LONG).show();
                }
            } catch (JSONException e) {
                // JSON error
                e.printStackTrace();
                Toast.makeText(getApplicationContext(), "Json error: " + e.getMessage(), Toast.LENGTH_LONG).show();
            }

SqlHandler.java

private static final String BR_CODE = "br_code";
private static final String MEM_ID = "mem_id";
private static final String MEM_USERNAME = "username";
private static final String MEM_EMAIL = "email";
private static final String MEM_CREATED_AT = "created_at";
public SQLiteHandler(Context context) {
    super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
// Creating Tables
@Override
public void onCreate(SQLiteDatabase db) {
    String CREATE_LOGIN_TABLE = "CREATE TABLE " + TABLE_MEMBERS + "("
            + BR_CODE + " INTEGER,"
            + MEM_ID + " INTEGER PRIMARY KEY,"
            + MEM_USERNAME + " TEXT,"
            + MEM_EMAIL + " TEXT UNIQUE,"
            + MEM_CREATED_AT + " TEXT" + ")";
    db.execSQL(CREATE_LOGIN_TABLE);
    Log.d(TAG, "Database tables created");
}
// Upgrading database
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    // Drop older table if existed
    db.execSQL("DROP TABLE IF EXISTS " + TABLE_MEMBERS);
    // Create tables again
    onCreate(db);
}
/**
 * Storing user details in database
 * */
public void addUser(String br_code, String mem_id, String username, String email, String created_at) {
    SQLiteDatabase db = this.getWritableDatabase();
    ContentValues values = new ContentValues();
    values.put(BR_CODE, br_code); // branch code
    values.put(MEM_ID, mem_id); // mem id
    values.put(MEM_USERNAME, username); // username
    values.put(MEM_EMAIL, email); // Email
    values.put(MEM_CREATED_AT, created_at); // Created At
    // Inserting Row
    long id = db.insert(TABLE_MEMBERS, null, values);
    db.close(); // Closing database connection
    Log.d(TAG, "New user inserted into sqlite: " + id);
}
/**
 * Getting user data from database
 * */
public HashMap<String, String> getUserDetails() {
    HashMap<String, String> user = new HashMap<String, String>();
    String selectQuery = "SELECT  * FROM " + TABLE_MEMBERS;
    SQLiteDatabase db = this.getReadableDatabase();
    Cursor cursor = db.rawQuery(selectQuery, null);
    // Move to first row
    cursor.moveToFirst();
    if (cursor.getCount() > 0) {
        user.put("br_code", cursor.getString(1));
        user.put("mem_id", cursor.getString(2));
        user.put("username", cursor.getString(3));
        user.put("email", cursor.getString(4));
        user.put("created_at", cursor.getString(5));
    }
    cursor.close();
    db.close();
    // return user
    Log.d(TAG, "Fetching user from Sqlite: " + user.toString());
    return user;
}

错误日志

        05-19 16:23:24.730 1679-1679/info.androidhive.loginandregistration E/AndroidRuntime: FATAL EXCEPTION: main
     java.lang.RuntimeException: Unable to start activity ComponentInfo{info.androidhive.loginandregistration/info.androidhive.loginandregistration.activity.MainActivity}: java.lang.IllegalStateException: Couldn't read row 0, col 5 from CursorWindow.  Make sure the Cursor is initialized correctly before accessing data from it.
         at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2059)
         at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
         at android.app.ActivityThread.access$600(ActivityThread.java:130)
         at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
         at android.os.Handler.dispatchMessage(Handler.java:99)
         at android.os.Looper.loop(Looper.java:137)
         at android.app.ActivityThread.main(ActivityThread.java:4746)
         at java.lang.reflect.Method.invokeNative(Native Method)
         at java.lang.reflect.Method.invoke(Method.java:511)
         at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:917)
         at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:684)
         at dalvik.system.NativeStart.main(Native Method)
      Caused by: java.lang.IllegalStateException: Couldn't read row 0, col 5 from CursorWindow.  Make sure the Cursor is initialized correctly before accessing data from it.
         at android.database.CursorWindow.nativeGetString(Native Method)
         at android.database.CursorWindow.getString(CursorWindow.java:434)
         at android.database.AbstractWindowedCursor.getString(AbstractWindowedCursor.java:51)
         at info.androidhive.loginandregistration.helper.SQLiteHandler.getUserDetails(SQLiteHandler.java:102)
         at info.androidhive.loginandregistration.activity.MainActivity.onCreate(MainActivity.java:45)
         at android.app.Activity.performCreate(Activity.java:5080)
         at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1079)
         at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2023)
         at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084) 
         at android.app.ActivityThread.access$600(ActivityThread.java:130) 
         at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195) 
         at android.os.Handler.dispatchMessage(Handler.java:99) 
         at android.os.Looper.loop(Looper.java:137) 
         at android.app.ActivityThread.main(ActivityThread.java:4746) 
         at java.lang.reflect.Method.invokeNative(Native Method) 
         at java.lang.reflect.Method.invoke(Method.java:511) 
         at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:917) 
         at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:684) 
         at dalvik.system.NativeStart.main(Native Method) 
    05-19 16:23:27.420 1679-1679/info.androidhive.loginandregistration I/Process: Sending signal. PID: 1679 SIG: 9

Answer 1

无法从游标窗口读取第 0 行、第 5 行。

您有 5 列，起始索引为 0，但从 1 开始

所以错误在这里：

if (cursor.getCount() > 0) {
    user.put("br_code", cursor.getString(1));
    user.put("mem_id", cursor.getString(2));
    user.put("username", cursor.getString(3));
    user.put("email", cursor.getString(4));
    user.put("created_at", cursor.getString(5));
}

只需从 id 中减去 1

if (cursor.getCount() > 0) {
    user.put("br_code", cursor.getString(0));
    user.put("mem_id", cursor.getString(1));
    user.put("username", cursor.getString(2));
    user.put("email", cursor.getString(3));
    user.put("created_at", cursor.getString(4));
}

Answer 2

您要将 LoginActivity 转换为 MainActivty。您是否在清单文件中定义了 MainActivity？如果是，请在此处检查从数据库获取数据的下一种方式。

  Cursor cursor = db.rawQuery(selectQuery, null);
        if (cursor.moveToFirst()) {
            do {
                Contacts contact = new Contacts();
                contact.set_id(cursor.getInt(0));
                contact.set_addBookingId(cursor.getInt(1));
                contact.set_bookingDate(cursor.getString(2));
                contact.set_pubId(Integer.parseInt(cursor.getString(3)));
                contact.set_pubdate(cursor.getString(4));
                contactList.add(contact);
            } while (cursor.moveToNext());
        }

        return contactList;
    }