127.0.0.1: ページの作成:「==db接続サンプル== *DatabaseHelper.java import android.content.Context; import android.database.sqlite.SQLiteDatabase; import android.database.sqlite.SQLiteOpenH...」

2015-05-19T18:10:51Z

ページの作成:「==db接続サンプル== *DatabaseHelper.java import android.content.Context; import android.database.sqlite.SQLiteDatabase; import android.database.sqlite.SQLiteOpenH...」

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==db接続サンプル==
*DatabaseHelper.java
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
public class DatabaseHelper extends SQLiteOpenHelper {
static final String DATABASE_NAME = "mytest.db";
static final int DATABASE_VERSION = 1;
public DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
ImageDao.createTable(db);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
ImageDao.dropCreateTable(db);
}
public SQLiteDatabase open() {
return super.getWritableDatabase();
}
public void close(){
super.close();
}
}

*ImageDao.java
import java.util.ArrayList;
import java.util.Date;
import java.util.HashMap;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
public class ImageDao {
private Context mContext;
private SQLiteDatabase mDb;
public static final String TABLE_NAME = "images";
public static final String COL_ID = "_id";
public static final String COL_IMAGE_ID = "image_id";
public static final String COL_URL = "url";
public static final String COL_LASTUPDATE = "lastupdate";
public ImageDao(Context context) {
mContext = context;
}
public void connection() {
DatabaseHelper helper = new DatabaseHelper(mContext);
mDb = helper.open();
}
public void close() {
mDb.close();
}
public static void createTable(SQLiteDatabase db) {
db.execSQL(
"CREATE TABLE " + TABLE_NAME + " ("
+ COL_ID + " INTEGER PRIMARY KEY AUTOINCREMENT,"
+ COL_IMAGE_ID + " TEXT,"
+ COL_URL + " TEXT NOT NULL,"
+ COL_LASTUPDATE + " TEXT NOT NULL);");
}
public static void dropCreateTable(SQLiteDatabase db) {
db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
createTable(db);
}
public boolean deleteAll(){
return mDb.delete(TABLE_NAME, null, null) > 0;
}
public boolean deleteById(int id){
String[] selectArgs = new String[]{ String.valueOf(id) };
return mDb.delete(TABLE_NAME, COL_ID + "=?", selectArgs) > 0;
}
public ArrayList<<nowiki />HashMap<<nowiki />String, String>> findAll() {
ArrayList<<nowiki />HashMap<<nowiki />String, String>> images = new ArrayList<<nowiki />HashMap<<nowiki />String, String>>();
Cursor c = mDb.query(TABLE_NAME, null, null, null, null, null, COL_ID);
if (c.moveToFirst()) {
do {
HashMap<<nowiki />String, String> image = new HashMap<<nowiki />String, String>();
image.put(ImageDao.COL_ID, String.valueOf(c.getInt(c.getColumnIndex(ImageDao.COL_ID))));
image.put(ImageDao.COL_IMAGE_ID, c.getString(c.getColumnIndex(ImageDao.COL_IMAGE_ID)));
image.put(ImageDao.COL_URL, c.getString(c.getColumnIndex(ImageDao.COL_URL)));
image.put(ImageDao.COL_LASTUPDATE, c.getString(c.getColumnIndex(ImageDao.COL_LASTUPDATE)));
images.add(image);
} while(c.moveToNext());
}
c.close();
return images;
}
public HashMap<<nowiki />String, String> findRowById(int id) {
String[] selectArgs = new String[]{ String.valueOf(id) };
Cursor c = mDb.query(TABLE_NAME, null, COL_ID + "=?", selectArgs, null, null, null);
HashMap<<nowiki />String, String> image = new HashMap<<nowiki />String, String>();
if (c.moveToFirst()) {
if (c.getCount() > 0 ) {
image.put(ImageDao.COL_ID, String.valueOf(c.getInt(c.getColumnIndex(ImageDao.COL_ID))));
image.put(ImageDao.COL_IMAGE_ID, c.getString(c.getColumnIndex(ImageDao.COL_IMAGE_ID)));
image.put(ImageDao.COL_URL, c.getString(c.getColumnIndex(ImageDao.COL_URL)));
image.put(ImageDao.COL_LASTUPDATE, c.getString(c.getColumnIndex(ImageDao.COL_LASTUPDATE)));
}
}
c.close();
return image;
}
public HashMap<<nowiki />String, String> findRowByImageId(String imageId) {
String[] selectArgs = new String[]{ imageId };
Cursor c = mDb.query(TABLE_NAME, null, COL_IMAGE_ID + "=?", selectArgs, null, null, null);
HashMap<<nowiki />String, String> image = new HashMap<<nowiki />String, String>();
if (c.moveToFirst()) {
if (c.getCount() > 0 ) {
image.put(ImageDao.COL_ID, String.valueOf(c.getInt(c.getColumnIndex(ImageDao.COL_ID))));
image.put(ImageDao.COL_IMAGE_ID, c.getString(c.getColumnIndex(ImageDao.COL_IMAGE_ID)));
image.put(ImageDao.COL_URL, c.getString(c.getColumnIndex(ImageDao.COL_URL)));
image.put(ImageDao.COL_LASTUPDATE, c.getString(c.getColumnIndex(ImageDao.COL_LASTUPDATE)));
}
}
c.close();
return image;
}
public void insertImageIdUrl(String imageId, String url){
HashMap<<nowiki />String, String> image = new HashMap<<nowiki />String, String>();
image.put(COL_IMAGE_ID, imageId);
image.put(COL_URL, url);
insert(image);
}
public void insert(HashMap<<nowiki />String, String> image){
Date dateNow = new Date();
ContentValues values = new ContentValues();
values.put(COL_IMAGE_ID, image.get(COL_IMAGE_ID));
values.put(COL_URL, image.get(COL_URL));
values.put(COL_LASTUPDATE, dateNow.toLocaleString());
mDb.insertOrThrow(TABLE_NAME, null, values);
}
public void updateByImageId(HashMap<<nowiki />String, String> image, String imageId) {
Date dateNow = new Date();
ContentValues values = new ContentValues();
values.put(COL_IMAGE_ID, image.get(COL_IMAGE_ID));
values.put(COL_URL, image.get(COL_URL_THUMB));
values.put(COL_LASTUPDATE, dateNow.toLocaleString());
mDb.update(TABLE_NAME, values, COL_IMAGE_ID + "=?", new String[] {imageId});
}
}

*DbTestActivity.java
import java.util.ArrayList;
import java.util.HashMap;
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
public class DbTestActivity extends Activity {
private static String TAG = "DbTestActivity";
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.db_layout);
}
@Override
public void onStart() {
super.onStart();
ImageDao dao = new ImageDao(getApplicationContext());
dao.connection();
dao.insertImageIdUrl("test1", "hoge1");
ArrayList<<nowiki />HashMap<<nowiki />String, String>> users = dao.findAll();
//HashMap<<nowiki />String, String> image = dao.findRowById(1);
HashMap<<nowiki />String, String> image = dao.findRowByImageId("test1");
dao.close();
for (HashMap<<nowiki />String, String> user : users) {
Log.d(TAG, "id " + user.get("_id"));
Log.d(TAG, "image_id " + user.get("image_id"));
Log.d(TAG, "url " + user.get("url"));
}
Log.d(TAG, "id " + image.get("_id"));
Log.d(TAG, "image_id " + image.get("image_id"));
Log.d(TAG, "url " + image.get("url"));
}
}

==以下エラー。データを取得したら、cursor.moveToFirst();をする==
CursorIndexOutOfBoundsException

==以下エラー。dbをcloseしてるか確認。==
close() was never explicitly called on database '/data/data/com.project1/databases/test.db'

==以下エラー。カーソルを閉じてるか確認==
Finalizing a Cursor that has not been deactivated or closed. database

Android/db/基本 - 変更履歴

127.0.0.1: ページの作成:「==db接続サンプル== *DatabaseHelper.java import android.content.Context; import android.database.sqlite.SQLiteDatabase; import android.database.sqlite.SQLiteOpenH...」