我有 SQlite 数据库，我将其保存在项目的 Assets 文件夹中。 从 Assets 文件夹中，我正在将 sqlite db 复制到 data\data\packagename\MYSHOES.sqlite。 我成功地从该数据库检索数据，但是当 我正在尝试插入数据，但它没有执行任何操作。没有错误消息。 下面是我的代码。
public class Shoedb extends SQLiteOpenHelper {
private SQLiteDatabase myDataBase;
private final Context myContext;
private static String DB_DIR = "/data/data/com.customlistview/";
private static String DB_NAME = "MYSHOES.sqlite";
private static String DB_PATH = DB_DIR + DB_NAME;
boolean dbfnd;
Cursor chk;
private String TAG = "Database Helper";
public Shoedb(Context context) {
super(context, Shoedb.DB_NAME, null, 1);
this.myContext = context;
// DB_PATH=myContext.getDatabasePath(DB_NAME).getAbsolutePath();
System.out.println("My DataBase Path: " + DB_PATH);
try {
copyDataBase();
openDataBase();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public void createDataBase() throws IOException {
Log.e("createDataBase1", "+++++++++++++");
boolean dbExist = checkDataBase();
if (dbExist) {
Log.e("createDataBase2", "++++++ database already exist");
// do nothing - database already exist
} else {
// this.getReadableDatabase();
try {
copyDataBase();
} catch (IOException e) {
throw new Error("Error copying database");
}
}
}
private boolean checkDataBase() {
SQLiteDatabase checkDB = null;
try {
String myPath = DB_PATH;
checkDB = SQLiteDatabase.openDatabase(myPath, null,
SQLiteDatabase.OPEN_READONLY);
} catch (SQLiteException e) {
// database does't exist yet.
}
if (checkDB != null) {
checkDB.close();
}
return checkDB != null ? true : false;
}
private void copyDataBase() throws IOException {
// Open your local db as the input stream
InputStream myInput = myContext.getAssets().open(DB_NAME);
// Path to the just created empty db
String outFileName = DB_PATH;
// Open the empty db as the output stream
OutputStream myOutput = new FileOutputStream(outFileName);
// transfer bytes from the inputfile to the outputfile
byte[] buffer = new byte[1024];
int length;
while ((length = myInput.read(buffer)) > 0) {
myOutput.write(buffer, 0, length);
}
// Close the streams
myOutput.flush();
myOutput.close();
myInput.close();
}
public static void copyFile(InputStream fromFile, OutputStream toFile)
throws IOException {
// transfer bytes from the inputfile to the outputfile
System.out.println("In copying.....");
byte[] buffer = new byte[1024];
int length;
try {
while ((length = fromFile.read(buffer)) > 0) {
toFile.write(buffer, 0, length);
System.out.println("Reading & writing the file....");
}
} catch (Exception e) {
System.out.println("Error in copy1 file :" + e.toString());
}
// Close the streams
finally {
try {
if (toFile != null) {
try {
toFile.flush();
} finally {
toFile.close();
}
}
} catch (Exception e) {
System.out.println("Error in copy2 file :" + e.toString());
} finally {
if (fromFile != null) {
fromFile.close();
System.out.println("File copied successfully.....");
}
}
}
}
public static void copyFile(String fromFile, String toFile)
throws IOException {
copyFile(new FileInputStream(fromFile), new FileOutputStream(toFile));
}
// Open the database
public void openDataBase() {
String myPath = DB_PATH;
try {
myDataBase = SQLiteDatabase.openDatabase(myPath, null,
SQLiteDatabase.OPEN_READWRITE);
System.out.println(myDataBase.toString()
+ " Database found....................!!!!!!!");
dbfnd = true;
} catch (Exception e) {
System.out.println("Database not found....................!!!!!!!");
// TODO: handle exception
dbfnd = false;
}
}
public SQLiteDatabase getReadableDatabase() {
myDataBase = SQLiteDatabase.openDatabase(DB_PATH, null,
SQLiteDatabase.OPEN_READONLY);
return myDataBase;
}
public SQLiteDatabase getWritableDatabase() {
myDataBase = SQLiteDatabase.openDatabase(DB_PATH, null,
SQLiteDatabase.OPEN_READWRITE);
return myDataBase;
}
@Override
public synchronized void close() {
if (myDataBase != null)
myDataBase.close();
super.close();
}
@Override
public void onCreate(SQLiteDatabase db) {
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
public Cursor get_Data(String selCat) {
chk = null;
try {
chk = myDataBase.rawQuery(
"select Image,Price,Category from shoe_info where Category='"
+ selCat + "'", null);
} catch (Exception e) {
Log.e(TAG, "Error in getshoeinfo");
e.printStackTrace();
return null;
}
return chk;
}
public Cursor get_DataImage(String pImage) {
// TODO Auto-generated method stub
chk = null;
try {
chk = myDataBase.rawQuery(
"select Image,Price,Category from shoe_info where Image='"
+ pImage + "'", null);
} catch (Exception e) {
Log.e(TAG, "Error in getshoeinfo");
e.printStackTrace();
return null;
}
return chk;
}
//This code is not working
public void put_DataImage(String pImage, String price, String id) {
// TODO Auto-generated method stub
chk = null;
try {
System.out
.println("insert into shoe_info(Image,Price,Category) values('"
+ pImage + "','" + price + "','" + id + "');");
myDataBase
.execSQL("insert into shoe_info(Image,Price,Category) values('"
+ pImage + "','" + price + "','" + id + "');");
} catch (Exception e) {
Log.e(TAG, "Error in getshoeinfo");
e.printStackTrace();
}
}
public void put_DataToCart(String image, String price, String pCat) {
// TODO Auto-generated method stub
Log.i(TAG, "Insert to mycarttttttttttttttttttt");
try {
System.out
.println("insert into mycart (Image,Price,category) values('"
+ image + "','" + price + "','" + pCat + "');");
myDataBase
.execSQL("insert into mycart(Image,Price,category) values('"
+ image + "','" + price + "','" + pCat + "')");
} catch (Exception e) {
Log.e(TAG, "Error in put_DataToCart");
e.printStackTrace();
}
}
public Cursor get_DataFromCart() {
chk = null;
try {
System.out.println("select Image,Price,category from mycart");
chk = myDataBase.rawQuery(
"select Image,Price,category from mycart", null);
} catch (Exception e) {
Log.e(TAG, "Error in getshoeinfo");
e.printStackTrace();
return null;
}
return chk;
}
}
最佳答案
尝试使用
SQLiteDatabase.OPEN_READWRITE 而不是 SQLiteDatabase.OPEN_READONLY
在 checkDataBase() 中打开与数据库的连接。目前与数据库的连接是只读的...
关于android - 无法将数据插入到 Android 中的 SQLite 数据库中，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/20160149/