【发布时间】:2011-07-08 13:48:29
【问题描述】:
好吧,我昨天和今天一直在与这个作斗争,我得到了一个简单的 SQLite 插入,它不断返回 -1 作为返回值,我在某处读到将主键名称更改为 _id,但没有做任何更改。
所以这里是代码的快照。 我的字段常量:
//BALLS TABLE
public static final String BALLS_TABLE = "balls";
public static final String BALL_ID = "id";
public static final String BALL_USERID = "userId";
public static final String BALL_MODEL = "model";
public static final String BALL_BRAND = "brand";
public static final String BALL_SERIAL = "serial";
public static final String BALL_NOTES = "notes";
public static final String BALL_IMAGE = "image";
然后在我的 createTables(SQLiteDatabase db) 上我得到了
//球桌
db.execSQL(
"create table " + BALLS_TABLE +" (" +
BALL_ID + " integer primary key autoincrement not null," +
BALL_USERID + "integer not null," +
BALL_MODEL + " text not null," +
BALL_BRAND + " text not null," +
BALL_SERIAL + " text not null," +
BALL_NOTES + " text not null," +
BALL_IMAGE + " blob" +
");");
表格的创建正在工作,因为我得到了其他已填充的表格。
最后是整个ball Helper类
package com.kegel.android.bowlermanager.data;
import java.io.ByteArrayOutputStream;
import java.util.ArrayList;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
public class BallHelper {
private SQLiteDatabase database;
private ArrayList<Ball> currentBalls;
private Context context;
public BallHelper(Context context,SQLiteDatabase database)
{
this.context = context;
this.database = database;
loadBalls();
}
public ArrayList<Ball> getCurrentBalls() {
return currentBalls;
}
public Boolean BallExists(long id)
{
for (Ball ball : currentBalls)
{
if (ball.getId() == id)
return true;
}
return false;
}
public Boolean BallExists(Ball u)
{
for (Ball ball : currentBalls)
{
if (ball.getId() == u.getId())
return true;
}
return false;
}
public void updateBall(Ball b) {
assert(null != b);
ByteArrayOutputStream baos = new ByteArrayOutputStream();
byte[] by = null;
if (b.getImage() != null )
{
Bitmap bmp = b.getImage();
bmp.compress(Bitmap.CompressFormat.PNG, 100, baos);
by = baos.toByteArray();
}
ContentValues values = new ContentValues();
values.put(SQLiteOpenDataHelper.BALL_USERID, 1);
values.put(SQLiteOpenDataHelper.BALL_MODEL, b.getModel());
values.put(SQLiteOpenDataHelper.BALL_BRAND , b.getBrand());
values.put(SQLiteOpenDataHelper.BALL_SERIAL , b.getSerial());
values.put(SQLiteOpenDataHelper.BALL_NOTES, b.getNotes());
values.put(SQLiteOpenDataHelper.BALL_IMAGE , by);
if (b.isValid())
{
if (b.getId() == 0)
{
b.setId(database.insert(SQLiteOpenDataHelper.BALLS_TABLE, null, values));
}
else
{
long id = b.getId();
String where = String.format("%s = %d", SQLiteOpenDataHelper.BALL_ID, id);
database.update(SQLiteOpenDataHelper.BALLS_TABLE, values, where, null);
}
loadBalls();
}
}
public void deleteBalls(Long id) {
String where = String.format("%s in (%s)", SQLiteOpenDataHelper.BALL_ID, id);
database.delete(SQLiteOpenDataHelper.BALLS_TABLE, where, null);
loadBalls();
}
public void deleteBalls(Ball u) {
String where = String.format("%s in (%s)", SQLiteOpenDataHelper.BALL_ID, u.getId());
database.delete(SQLiteOpenDataHelper.BALLS_TABLE, where, null);
loadBalls();
}
private void loadBalls() {
byte[] img = null;
currentBalls = new ArrayList<Ball>();
//try
//{
Cursor ballsCursor = database.query(SQLiteOpenDataHelper.BALLS_TABLE, new String[] {SQLiteOpenDataHelper.BALL_ID,SQLiteOpenDataHelper.USER_ID, SQLiteOpenDataHelper.BALL_MODEL, SQLiteOpenDataHelper.BALL_BRAND, SQLiteOpenDataHelper.BALL_SERIAL, SQLiteOpenDataHelper.BALL_NOTES, SQLiteOpenDataHelper.BALL_IMAGE}, null, null, null, null, null);
ballsCursor.moveToFirst();
Ball b;
if (! ballsCursor.isAfterLast()) {
do {
long id = ballsCursor.getInt(0);
long bowlerId = ballsCursor.getLong(1);
String model = ballsCursor.getString(2);
String brand = ballsCursor.getString(3);
String serial = ballsCursor.getString(4);
String notes = ballsCursor.getString(5);
img = ballsCursor.getBlob(6);
Bitmap bmp=BitmapFactory.decodeByteArray(img,0,img.length);
b = new Ball(context,bowlerId,model,brand,serial,notes);
b.setId(id);
b.setImage(bmp);
currentBalls.add(b);
} while (ballsCursor.moveToNext());
}
ballsCursor.close();
}
}
这里的第二双眼睛会派上用场!所以如果有人能在这里发现任何东西,或者让我知道我是否遗漏了一些东西,我将非常感激。我已经检查了 b 上的值(甚至通过了我的内部验证)但是像这样的插入会失败:
Bitmap bm = BitmapFactory.decodeResource(getResources(), R.drawable.fake_pofile);
Ball ball = new Ball(this,1, "Test", "Test", "", "");
ball.setImage(bm);
mHelper.updateBall(ball);
【问题讨论】:
-
日志中有任何异常或附加信息吗?
-
插入失败是怎么回事? Logcat 有消息吗?
-
首先,球 id 是自动增量(在您的创建表查询中定义),不确定在自动增量时插入具有定义 id 的球是否是个好主意...其次,我看到你正在使用布尔值而不是布尔值,因此您也可能使用 Integer 而不是 int 并且 Integer 是对象。当您检查 ball.getId() == 0 时,球的 id 无法初始化,可能导致 NullPointer 异常。请发布异常,以便查看问题所在;)
-
也不例外, database.Insert 返回一个 -1 ,而应该返回的是一个有效的生成的自动增量 ID。我对其他类使用相同的逻辑,它们完美地返回了 Id。我也处于测试阶段,所以我确信没有其他人在搞乱 setId o getId。谢谢大家的帮助。
标签: java android database sqlite insert