如何创建一个表，BLOB类型的一个DBAdapter列 [英] How to create a Table with a column of type BLOB in a DBAdapter
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问题描述
我有一个全球性的DBAdapter也为每个表之一。在我的全局DB-适配器我添加类型为BLOB的列。但我没有得到什么，我在我的DBAdapter更改为特定的表。我需要改变那里，它也可与BLOB类型。
I have a global DBAdapter and also for each Table one. In my global DB-Adapter I added the type "BLOB" to the column. But i don't get what i have to change in my DBAdapter for the specific Table. What I need to change there that it also works with the BLOB type.
所以，在这里你去：
全球DBAdapter：
Global DBAdapter:
package de.retowaelchli.filterit.database;
import android.content.Context;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import de.retowaelchli.filterit.database.ADFilterDBAdapter;
public class DBAdapter {
public static final String DATABASE_NAME = "filterit";
public static final int DATABASE_VERSION = 1;
public static final String CREATE_TABLE_ADFILTER = "create table adfilter (_id integer primary key autoincrement, "
+ ADFilterDBAdapter.NAME+","
+ ADFilterDBAdapter.KEYWORD+","
+ ADFilterDBAdapter.CACHE + ");";
private static final String CREATE_TABLE_SFILTER = "create table sfilter (_id integer primary key autoincrement, "
+SFilterDBAdapter.NAME+","
+SFilterDBAdapter.KEYWORD+","
+SFilterDBAdapter.SMILEY+ ");";
private static final String CREATE_TABLE_ADMESSAGES = "create table admessages (_id integer primary key autoincrement, "
+MessagesDBAdapter.PHONENUMBER+","
+MessagesDBAdapter.MESSAGE+ ");";
//HERE I CHANGED IT TO BLOB!
private static final String CREATE_TABLE_SMILEY = " create table smiley (_id integer primary key autoincrement, "
+SmileyDBAdapter.SOURCE+" BLOB ,"
+SmileyDBAdapter.INFO+ ");";
private final Context context;
private DatabaseHelper DBHelper;
private SQLiteDatabase db;
/**
* Constructor
* @param ctx
*/
public DBAdapter(Context ctx)
{
this.context = ctx;
}
private static class DatabaseHelper extends SQLiteOpenHelper
{
DatabaseHelper(Context context)
{
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db)
{
db.execSQL(CREATE_TABLE_ADFILTER);
db.execSQL(CREATE_TABLE_SFILTER);
db.execSQL(CREATE_TABLE_ADMESSAGES);
db.execSQL(CREATE_TABLE_SMILEY);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion,
int newVersion)
{
// Adding any table mods to this guy here
}
}
/**
* open the db
* @return this
* @throws SQLException
* return type: DBAdapter
*/
public DBAdapter open() throws SQLException
{
this.DBHelper = new DatabaseHelper(this.context);
this.db = this.DBHelper.getWritableDatabase();
return this;
}
/**
* close the db
* return type: void
*/
public void close()
{
this.DBHelper.close();
}
}
这是我这个表的DBAdapter：
This is my DBAdapter of this Table:
package de.retowaelchli.filterit.database;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
public class SmileyDBAdapter {
public static final String ROW_ID = "_id";
public static final String SOURCE = "source";
public static final String INFO = "info";
private static final String DATABASE_TABLE = "admessages";
private DatabaseHelper mDbHelper;
private SQLiteDatabase mDb;
private final Context mCtx;
private static class DatabaseHelper extends SQLiteOpenHelper {
DatabaseHelper(Context context) {
super(context, DBAdapter.DATABASE_NAME, null, DBAdapter.DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
}
/**
* Constructor - takes the context to allow the database to be
* opened/created
*
* @param ctx
* the Context within which to work
*/
public SmileyDBAdapter(Context ctx) {
this.mCtx = ctx;
}
public SmileyDBAdapter open() throws SQLException {
this.mDbHelper = new DatabaseHelper(this.mCtx);
this.mDb = this.mDbHelper.getWritableDatabase();
return this;
}
/**
* close return type: void
*/
public void close() {
this.mDbHelper.close();
}
public long createSmiley(String source, String info ){
ContentValues initialValues = new ContentValues();
initialValues.put(SOURCE, source);
initialValues.put(INFO, info);
return this.mDb.insert(DATABASE_TABLE, null, initialValues);
}
public boolean deleteSmiley(long rowId) {
return this.mDb.delete(DATABASE_TABLE, ROW_ID + "=" + rowId, null) > 0; //$NON-NLS-1$
}
public Cursor getAllSmileys() {
return this.mDb.query(DATABASE_TABLE, new String[] { ROW_ID,
SOURCE, INFO }, null, null, null, null, null);
}
public Cursor getSmiley(long rowId) throws SQLException {
Cursor mCursor =
this.mDb.query(true, DATABASE_TABLE, new String[] { ROW_ID, SOURCE,
INFO }, ROW_ID + "=" + rowId, null, null, null, null, null);
if (mCursor != null) {
mCursor.moveToFirst();
}
return mCursor;
}
public boolean updateSmiley(long rowId, String source, String info,
String cache){
ContentValues args = new ContentValues();
args.put(SOURCE, source);
args.put(INFO, info);
return this.mDb.update(DATABASE_TABLE, args, ROW_ID + "=" + rowId, null) >0;
}
}
我需要在我的SmileyDBAdapter改变，使其工作。它支持的类型的BLOB。我试着本作薮小时-.-后真的沮丧
What I need to change in my SmileyDBAdapter to bring it working. That it supports the type BLOB. Im really frustrated after trying this for serval hours -.-
THX提前为你的答案
Thx in Advance for your Answer
最好的问候
野生动物园
推荐答案
勾选此code为插入从数据库的BLOB的网页链接和存储图像和ImageView的显示。
Check this Code for Inserting the Image from the Web link and store in the Database as BLOB and shown in ImageView .
Java的code：
Java Code :
CategoryDetails.Java
public class CategoryDetails extends Activity {
public NotesDbAdapter mDbHelper;
ByteArrayBuffer baf ;
private Cursor mNotesCursor;
ImageView img;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mDbHelper = new NotesDbAdapter(this);
mDbHelper.open();
new Task_like_flag().execute();
img=(ImageView)findViewById(R.id.ImageView01);
}
public Bitmap convertBlobToBitmap(byte[] blobByteArray) {
Bitmap tempBitmap=null;
if(blobByteArray!=null)
tempBitmap = BitmapFactory.decodeByteArray(blobByteArray, 0, blobByteArray.length);
return tempBitmap;
}
public class Task_like_flag extends AsyncTask<String, Void, Void> {
private final ProgressDialog dialog = new ProgressDialog(CategoryDetails.this);
JSONObject object_feed;
// can use UI thread here
protected void onPreExecute() {
this.dialog.setMessage("Loading...");
this.dialog.setCancelable(false);
this.dialog.show();
}
@Override
protected Void doInBackground(String... params) {
URL url = null;
try {
url = new URL("http://www.theblacksheeponline.com/uploaded/Quick_images/681314276069brewehas.jpg");
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} //http://example.com/image.jpg
//open the connection
URLConnection ucon = null;
try {
ucon = url.openConnection();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
//buffer the download
InputStream is = null;
try {
is = ucon.getInputStream();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
BufferedInputStream bis = new BufferedInputStream(is,128);
baf = new ByteArrayBuffer(128);
//get the bytes one by one
int current = 0;
try {
while ((current = bis.read()) != -1) {
baf.append((byte) current);
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
mDbHelper.createNote(baf.toByteArray());
return null;
}
@Override
protected void onPostExecute(Void result) {
byte[] imageByteArray;
Bitmap theImage = null;
try{
mNotesCursor = mDbHelper.fetchAllNotes();
startManagingCursor(mNotesCursor);
if (mNotesCursor.moveToFirst()) {
do {
imageByteArray = mNotesCursor.getBlob(mNotesCursor.getColumnIndex(NotesDbAdapter.KEY_IMAGE));
ByteArrayInputStream imageStream = new ByteArrayInputStream(imageByteArray);
theImage= BitmapFactory.decodeStream(imageStream);
} while (mNotesCursor.moveToNext());
}
}catch(Exception e){
Log.v("Excep", ""+e);
}
img.setImageBitmap(theImage);
if (this.dialog.isShowing()) {
this.dialog.dismiss();
}
}
}
}
NotesDbAdapter.Class
public class NotesDbAdapter {
public static final String KEY_CATEGORY = "category";
public static final String KEY_DATE = "notes_date";
public static final String KEY_DESC = "item_desc";
public static final String KEY_PRIZE = "item_prize";
public static final String KEY_MODE = "mode";
public static final String KEY_MONTH = "month";
public static final String KEY_IMAGE = "img";
public static final String KEY_ROWID = "_id";
private static final String TAG = "NotesDbAdapter";
private DatabaseHelper mDbHelper;
private SQLiteDatabase mDb;
/**
* Database creation sql statement
*/
private static final String DATABASE_CREATE =
"create table notes (_id integer primary key autoincrement, "
+ "img BLOB not null);";
private static final String DATABASE_NAME = "data";
private static final String DATABASE_TABLE = "notes";
private static final int DATABASE_VERSION = 2;
private final Context mCtx;
private static class DatabaseHelper extends SQLiteOpenHelper {
DatabaseHelper(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(TAG, "Upgrading database from version " + oldVersion + " to "
+ newVersion + ", which will destroy all old data");
db.execSQL("DROP TABLE IF EXISTS notes");
onCreate(db);
}
}
/**
* Constructor - takes the context to allow the database to be
* opened/created
*
* @param ctx the Context within which to work
*/
public NotesDbAdapter(Context ctx) {
this.mCtx = ctx;
}
/**
* Open the notes database. If it cannot be opened, try to create a new
* instance of the database. If it cannot be created, throw an exception to
* signal the failure
*
* @return this (self reference, allowing this to be chained in an
* initialization call)
* @throws SQLException if the database could be neither opened or created
*/
public NotesDbAdapter open() throws SQLException {
mDbHelper = new DatabaseHelper(mCtx);
mDb = mDbHelper.getWritableDatabase();
return this;
}
public void close() {
mDbHelper.close();
}
/**
* Create a new note using the title and body provided. If the note is
* successfully created return the new rowId for that note, otherwise return
* a -1 to indicate failure.
*
* @param title the title of the note
* @param body the body of the note
* @return rowId or -1 if failed
*/
public long createNote(byte[] img) {
byte yes[]=img;
ContentValues initialValues = new ContentValues();
initialValues.put(KEY_IMAGE, yes);
Log.v("row", ""+mDb.insert(DATABASE_TABLE, null, initialValues));
return mDb.insert(DATABASE_TABLE, null, initialValues);
}
/**
* Return a Cursor over the list of all notes in the database
*
* @return Cursor over all notes
*/
public Cursor fetchAllNotes() {
return mDb.query(DATABASE_TABLE, null, null, null, null, null, null);
} }
main.xml中：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<ImageView android:id="@+id/ImageView01" android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@drawable/icon"/>
</LinearLayout>
让我知道如果你发现任何问题。
Let me know if you find any Difficulty.
由于Venky ..
Thanks Venky..
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