Java Android SQL中创建联系人的空指针

我有一个LinkedList来保存我的观点，但我知道我想使用sqlite数据库来代替

这是我的point类，我只列出变量。他们都有能手和二传手

public Point(String Serial, String Observation, boolean tir, double x, double y, int networkNumber, int potencia,
                 int ColumnNr, int Column, int lamp, int armor, int lampState) {
        this.Serial = Serial;
        this.Observations = Observation;
        this.tir = tir;
        this.x = x;
        this.y = y;
        this.networkNumber = networkNumber;
        this.potencia = potencia;
        this.ColumnNr = ColumnNr;
        this.Column = Column;
        this.lamp = lamp;
        this.armor = armor;
        this.lampState = lampState;
    }

这是我的观点

public class PointsDB extends SQLiteOpenHelper {

    public static final String ID = "_id";
    public static final String SERIAL = "Serial";
    public static final String OBSERVATIONS = "Observações";
    public static final String TIR = "tir";
    public static final String X = "X";
    public static final String Y = "Y";
    public static final String NETWORKNUMBER = "Rede";
    public static final String POTENCIA = "Potencia";
    public static final String COLUMNNR = "Numero Coluna";
    public static final String COLUMN = "Coluna";
    public static final String LAMP = "Lampada";
    public static final String ARMOR = "Armadura";
    public static final String LAMPSTATE = "Estado da Lampada";
    private static final int DATABASE_VERSION = 1;

    private static final String DATABASE_NAME = "pontos.db";
    public static final String TABLE_NAME = "pontos";
    private static final String DATABASE_CREATE = "create table "
            + TABLE_NAME + "( " + ID
            + " integer primary key autoincrement, " + SERIAL
            + " text not null, " + OBSERVATIONS + " text not null, "
            + TIR + " text not null" +
            ", " + X + " text not null " + Y + " text not null, " + NETWORKNUMBER + " text not null, " + POTENCIA + " text not null, "
            + COLUMNNR + " text not null, " + COLUMN + " text not null, " + LAMP + " text not null, "
            + ARMOR + " text not null, " + LAMPSTATE + " text not null);";

    public PointsDB(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL(DATABASE_CREATE);
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        Log.w(PointsDB.class.getName(),
                "Upgrading database from version " + oldVersion + " to "
                        + newVersion + ", which will destroy all old data"
        );
        db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
        onCreate(db);
    }
}

这是我的观点

public class PointsDBAdapter {
    private SQLiteDatabase database;
    private PointsDB points;
    private String[] allColumns = {PointsDB.ID, PointsDB.SERIAL, PointsDB.OBSERVATIONS, PointsDB.TIR, PointsDB.X, PointsDB.Y,
    PointsDB.NETWORKNUMBER, PointsDB.POTENCIA, PointsDB.COLUMNNR, PointsDB.COLUMN, PointsDB.LAMP, PointsDB.ARMOR, PointsDB.LAMPSTATE};

    public PointsDBAdapter(Context context) {
        points = new PointsDB(context);
    }

    public Point createContacto(String Serial, String Observation, boolean tir, double x, double y, int networkNumber, int potencia,
                                int ColumnNr, int Column, int lamp, int armor, int lampState) {
        ContentValues values = new ContentValues();
        values.put(PointsDB.SERIAL, Serial);
        Log.d("1", Serial);
        values.put(PointsDB.OBSERVATIONS, Observation);
        Log.d("2", Observation);
        values.put(PointsDB.TIR,tir);
        Log.d("3", "tir" + tir);
        values.put(PointsDB.X, x);
        Log.d("4","x" + x);
        values.put(PointsDB.Y, y);
        values.put(PointsDB.NETWORKNUMBER, networkNumber);
        values.put(PointsDB.POTENCIA, potencia);
        values.put(PointsDB.COLUMNNR, ColumnNr);
        values.put(PointsDB.COLUMN, Column);
        values.put(PointsDB.LAMP, lamp);
        values.put(PointsDB.ARMOR, armor);
        values.put(PointsDB.LAMPSTATE, lampState);
        long insertId = database.insert(PointsDB.TABLE_NAME, null, values);
        // To show how to query
        Cursor cursor = database.query(PointsDB.TABLE_NAME, allColumns, PointsDB.ID + " = " +
                insertId, null,null, null, null);
        cursor.moveToFirst();
        return cursorToPoint(cursor);
    }

    private Point cursorToPoint(Cursor cursor) {
        Point point = new
                Point(cursor.getString(0), cursor.getString(1), Boolean.parseBoolean(cursor.getString(2)), Integer.parseInt(cursor.getString(3)),
                Integer.parseInt(cursor.getString(4)), Integer.parseInt(cursor.getString(5)), Integer.parseInt(cursor.getString(6)),
                Integer.parseInt(cursor.getString(7)), Integer.parseInt(cursor.getString(8)), Integer.parseInt(cursor.getString(9)),
                Integer.parseInt(cursor.getString(10)), Integer.parseInt(cursor.getString(11)));
        return point;
    }

    public void deletePoint(int idPoint){
        database.delete(PointsDB.TABLE_NAME, PointsDB.ID + " = " + idPoint,
                null);
    }

    public Cursor getContactos(){
        Cursor cursor = database.rawQuery("select _id, Serial,Observações,tir, X, Y, Rede, Potencia, Numero Coluna, Coluna," +
                        "Lampada, Armadura, Estado de Lampada from pontos", null);
        return cursor;
    }

    public Point getPoint(int idPoint){
        Cursor cursor = database.query(PointsDB.TABLE_NAME, allColumns, PointsDB.ID + " = " +
                idPoint, null,null, null, null);
        cursor.moveToFirst();
        return cursorToPoint(cursor);
    }

    public int getSize() {
        String sql = "SELECT COUNT(*) FROM " + PointsDB.TABLE_NAME;
        SQLiteStatement statement = database.compileStatement(sql);
        return (int) statement.simpleQueryForLong();
    }

    public long count() {
        return DatabaseUtils.queryNumEntries(database,PointsDB.TABLE_NAME);
    }
}

最后，我有一个CreatePoint类，它在我的CreateView中有：

      final EditText SerialField = (EditText) view.findViewById(R.id.Serial);
        final EditText ObservationField = (EditText) view.findViewById(R.id.Observation);
        final EditText XField = (EditText) view.findViewById(R.id.XField);
        final EditText YField = (EditText) view.findViewById(R.id.YField);
        final EditText columnNrField = (EditText) view.findViewById(R.id.ColumnNr);
        final EditText intensityField = (EditText) view.findViewById(R.id.Intensity);
        final CheckBox status = (CheckBox) view.findViewById(R.id.checkBox);
        final Spinner spinner = (Spinner)view.findViewById(R.id.spinner5);
        final Spinner networkSpinner = (Spinner)view.findViewById(R.id.spinner1);
        final Spinner columnSpinner = (Spinner)view.findViewById(R.id.spinner2);
        final Spinner lampSpinner = (Spinner)view.findViewById(R.id.spinner3);
        final Spinner armorSpinner = (Spinner)view.findViewById(R.id.spinner4);

 Button buttonGuardar = (Button) view.findViewById(R.id.buttonGuardar);
            buttonGuardar.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {
                    String Serial = SerialField.getText().toString();
                    String Observation = ObservationField.getText().toString();
                    double X = Double.parseDouble(XField.getText().toString());
                    double Y = Double.parseDouble(YField.getText().toString());
                    int columnNumber = Integer.parseInt(columnNrField.getText().toString());
                    int intensity = Integer.parseInt(intensityField.getText().toString());
                    int networkToSet = networkSpinner.getSelectedItemPosition();
                    boolean checkBoxStatus = status.isChecked();
                    int valToSet = spinner.getSelectedItemPosition();
                    int setColumn = columnSpinner.getSelectedItemPosition();
                    int setLamp = lampSpinner.getSelectedItemPosition();
                    int setArmor = armorSpinner.getSelectedItemPosition();

pointsList.createContacto(Serial, Observation, checkBoxStatus, X, Y, networkToSet, columnNumber, intensity, setColumn, setLamp, setArmor, valToSet);

                    Fragment fragment = new PointsList();
                    FragmentManager fragmentManager = getActivity().getSupportFragmentManager();
                    fragmentManager.beginTransaction()
                            .replace(R.id.container, fragment)
                            .commit();
                }
            });

但当我试图创建一个点时，它不起作用

我的logcat错误指向：

long insertId = database.insert(PointsDB.TABLE_NAME, null, values);

顺便说一下，这是：

04-15 15:51:56.950  16194-16194/com.example.testlayout.app D/dalvikvm﹕ GC_FOR_ALLOC freed 186K, 3% free 8172K/8396K, paused 15ms, total 15ms
04-15 15:52:02.880  16194-16194/com.example.testlayout.app D/1﹕ oi
04-15 15:52:02.880  16194-16194/com.example.testlayout.app D/2﹕ hhh
04-15 15:52:02.880  16194-16194/com.example.testlayout.app D/3﹕ tirtrue
04-15 15:52:02.880  16194-16194/com.example.testlayout.app D/4﹕ x555.0
04-15 15:52:02.880  16194-16194/com.example.testlayout.app D/AndroidRuntime﹕ Shutting down VM
04-15 15:52:02.880  16194-16194/com.example.testlayout.app W/dalvikvm﹕ threadid=1: thread exiting with uncaught exception (group=0x418a1ba8)
04-15 15:52:02.880  16194-16194/com.example.testlayout.app E/AndroidRuntime﹕ FATAL EXCEPTION: main
    Process: com.example.testlayout.app, PID: 16194
    java.lang.NullPointerException
            at com.example.testlayout.app.PointsDBAdapter.createContacto(PointsDBAdapter.java:44)
            at com.example.testlayout.app.CreatePoint$1.onClick(CreatePoint.java:86)
            at android.view.View.performClick(View.java:4438)
            at android.view.View$PerformClick.run(View.java:18422)
            at android.os.Handler.handleCallback(Handler.java:733)
            at android.os.Handler.dispatchMessage(Handler.java:95)
            at android.os.Looper.loop(Looper.java:136)
            at android.app.ActivityThread.main(ActivityThread.java:5017)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:515)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
            at dalvik.system.NativeStart.main(Native Method)

---

在调用之前，确保初始化

数据库
变量：

long insertId = database.insert(PointsDB.TABLE_NAME, null, values);

你应该做：

database = points.getWritableDatabase();

您的
数据库
对象为空。确保它已初始化

您可能忘记了为
PointsDBAdapter
类提供
open（）
方法（并调用它）：

你错过了昏迷：

X text not null Y text not null

在X和Y的声明之间。这正是为什么自己编写所有SQL语句来创建表、查询基

使用诸如GreenDAO或ORMlite之类的库确实会使事情变得更简单。即使是编写自己的库也不是很复杂，而且会减少拼写错误的可能性。（我从来没有写过SQL。我曾经写过一个基本库，我多次对它进行扩展，从那时起就一直在使用它。）

此外，您还需要学习阅读错误消息。这一行非常明确。
您的日志cat指向一个SQL语法错误。因此，要解决这个问题，只需更改这一行

private static final String DATABASE_CREATE = "create table "
            + TABLE_NAME + "( " + ID
            + " integer primary key autoincrement, " + SERIAL
            + " text not null, " + OBSERVATIONS + " text not null, "
            + TIR + " text not null" +
            ", " + X + " text not null " + Y + " text not null, " + NETWORKNUMBER + " text not null, " + POTENCIA + " text not null, "
            + COLUMNNR + " text not null, " + COLUMN + " text not null, " + LAMP + " text not null, "
            + ARMOR + " text not null, " + LAMPSTATE + " text not null);";

用这个

private static final String DATABASE_CREATE = "create table "
        + TABLE_NAME + "( " + ID
        + " integer primary key autoincrement, " + SERIAL
        + " text not null, " + OBSERVATIONS + " text not null, "
        + TIR + " text not null" +
        ", " + X + " text not null, " + Y + " text not null, " + NETWORKNUMBER + " text not null, " + POTENCIA + " text not null, "
        + COLUMNNR + " text not null, " + COLUMN + " text not null, " + LAMP + " text not null, "
        + ARMOR + " text not null, " + LAMPSTATE + " text not null);";

如何初始化它？我的DBHelper是PointsDB，我是否缺少任何方法？我在哪里调用它？在我的DbAdapter、DBhelper或我的PointsList中？您更改了问题，输入了我们给您的提示，然后在它解决后，您的NullPointerException询问您遇到的下一个错误。这不是一个好的做法，因为它会使第一个答案毫无用处。已经标记了！很抱歉
private static final String DATABASE_CREATE = "create table "
        + TABLE_NAME + "( " + ID
        + " integer primary key autoincrement, " + SERIAL
        + " text not null, " + OBSERVATIONS + " text not null, "
        + TIR + " text not null" +
        ", " + X + " text not null, " + Y + " text not null, " + NETWORKNUMBER + " text not null, " + POTENCIA + " text not null, "
        + COLUMNNR + " text not null, " + COLUMN + " text not null, " + LAMP + " text not null, "
        + ARMOR + " text not null, " + LAMPSTATE + " text not null);";