次のリンクからSQLiteの例をダウンロードしました http://www.codegod.com/Android-ListView-with-dynamic-Images-AID590.aspx
SQLiteListActivity.java:
package com.codegod.android;
import java.util.ArrayList;
import android.app.ListActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ImageButton;
import android.widget.ListView;
import android.widget.AdapterView.OnItemClickListener;
public class SQLiteListActivity extends ListActivity implements View.OnClickListener {
private StockAdapter tableRowAdapter;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
try {
StocksManager stockMgr = new StocksManager(getApplicationContext());
// clear the table
stockMgr.clear();
// Add values to database
stockMgr.insert("APPL", "Apple Inc.");
stockMgr.insert("GOOG", "Google Inc.");
stockMgr.insert("LTSB", "Let's drink some beer");
// get the values from database
ArrayList<Stock> stocks = stockMgr.getStocks();
tableRowAdapter = new StockAdapter(
getApplicationContext(), R.layout.table_row, stocks);
setListAdapter(tableRowAdapter);
} catch (Exception ex) {
Log.e(ex.toString(), ex.toString());
}
}
@Override
public void onClick(View v) {
ImageButton button = (ImageButton) v;
Stock row = (Stock) button.getTag();
tableRowAdapter.deleteRow(row);
tableRowAdapter.notifyDataSetChanged();
}
}
Stock.java
package com.codegod.android;
public class Stock {
private String id;
private String description;
public Stock(String id, String description) {
this.id = id;
this.description = description;
}
public void setId(String id) {
this.id = id;
}
public String getId() {
return id;
}
public void setDescription(String description) {
this.description = description;
}
public String getDescription() {
return description;
}
}
StockAdapter.java
package com.codegod.android;
import java.util.List;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageButton;
import android.widget.TextView;
/**
* Adapter for Stock-objects
*
*/
public class StockAdapter extends BaseAdapter {
private final List<Stock> rows;
public StockAdapter(final Context context, final int itemResId,
final List<Stock> items) {
this.rows = items;
}
public int getCount() {
return this.rows.size();
}
public Object getItem(int position) {
return this.rows.get(position);
}
public long getItemId(int position) {
return position;
}
/**
* Set the content for a row here
*/
public View getView(int position, View convertView, ViewGroup parent) {
final Stock row = this.rows.get(position);
View itemView = null;
if (convertView == null) {
LayoutInflater inflater = (LayoutInflater) parent.getContext()
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
itemView = inflater.inflate(R.layout.table_row, null);
} else {
itemView = convertView;
}
// Set the text of the row
TextView txtId = (TextView) itemView.findViewById(R.id.rowId);
txtId.setText(row.getId());
TextView txtDesc = (TextView) itemView.findViewById(R.id.rowDesc);
txtDesc.setText(row.getDescription());
// Remember the row for each button so that we can refer to
// it when the button is clicked
ImageButton imgButton = (ImageButton) itemView.findViewById(R.id.icon);
imgButton.setTag(row);
return itemView;
}
/**
* Delete a row from the list of rows
* @param row row to be deleted
*/
public void deleteRow(Stock row) {
if(this.rows.contains(row)) {
this.rows.remove(row);
}
}
}
StocksManager.java
package com.codegod.android;
import java.util.ArrayList;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.util.Log;
import com.codegod.android.db.OpenDbHelper;
public class StocksManager {
private OpenDbHelper dbHelper;
private static final String STOCK_TABLE = "Stock";
private static final String STOCK_ID = "stock_id";
private static final String STOCK_DESC = "stock_desc";
private static final String SELECT_STOCKS = "SELECT * FROM " + STOCK_TABLE;
public StocksManager(Context context) {
dbHelper = new OpenDbHelper(context, STOCK_TABLE, STOCK_ID + " TEXT,"
+ STOCK_DESC + " TEXT");
}
/**
* Insert a Stock-value into database
* @param stockId id of the stock
* @param stockDesc description of the stock
* @return success or fail
*/
public boolean insert(String stockId, String stockDesc) {
try {
SQLiteDatabase sqlite = dbHelper.getWritableDatabase();
ContentValues initialValues = new ContentValues();
initialValues.put(STOCK_ID, stockId);
initialValues.put(STOCK_DESC, stockDesc);
sqlite.insert(STOCK_TABLE, null, initialValues);
} catch (SQLException sqlerror) {
Log.v("Insert into table error", sqlerror.getMessage());
return false;
}
return true;
}
/**
* Get all available stocks
* @return List of stocks
*/
public ArrayList<Stock> getStocks() {
ArrayList<Stock> stocks = new ArrayList<Stock>();
SQLiteDatabase sqliteDB = dbHelper.getReadableDatabase();
Cursor crsr = sqliteDB.rawQuery(SELECT_STOCKS, null);
crsr.moveToFirst();
for (int i = 0; i < crsr.getCount(); i++)
{
stocks.add(new Stock(crsr.getString(0), crsr.getString(1)));
crsr.moveToNext();
}
return stocks;
}
/**
* Clear the table
*/
public void clear() {
try {
SQLiteDatabase sqlite = dbHelper.getWritableDatabase();
sqlite.delete(STOCK_TABLE, "", null);
} catch (SQLException sqlerror) {
Log.v("delete from table error", sqlerror.getMessage());
}
}
}
OpenDBHelper.java
package com.codegod.android.db;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
public class OpenDbHelper extends SQLiteOpenHelper {
private static final int DATABASE_VERSION = 2;
private String createStatement = "";
/**
* Creates the OpenDbHelper
*
* @param context app-context
* @param tableName name of the table to open/create
* @param fields fields of the table to create
*/
public OpenDbHelper(Context context, String tableName, String fields) {
super(context, tableName, null, DATABASE_VERSION);
this.createStatement = "CREATE TABLE ";
this.createStatement += tableName + " (";
this.createStatement += fields + ");";
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL(this.createStatement);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int neVersion) {
// TODO Auto-generated method stub
}
}
Layout.xml:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent" android:layout_height="?android:attr/listPreferredItemHeight"
android:padding="4dip">
<TextView android:id="@+id/rowId" android:layout_width="fill_parent"
android:layout_height="26dip" android:singleLine="true"
android:textSize="20dip" android:textColor="#ffffff" android:text="Id..." />
<TextView android:id="@+id/rowDesc" android:layout_width="fill_parent"
android:text="Descr..." android:layout_height="20dip"
android:textSize="12dip" android:layout_below="@+id/rowId"
android:layout_alignParentBottom="true" android:textColor="#ffffff" />
<ImageButton android:id="@+id/icon" android:layout_width="wrap_content"
android:layout_height="wrap_content" android:src="@drawable/delete"
android:gravity="right" android:layout_alignParentRight="true"
android:onClick="onClick" />
</RelativeLayout>
データベースに接続されたリストビューと行を削除するための画像ボタンがありますが、削除結果をデータベースに保存するために変更したいのですが、削除後の変更はこの場所には保存されません。プロジェクトであり、ファイルエクスプローラーからプルした場合でも、データベースにはまだ3つの行がありますが、どのように変更すればよいですか?この問題について私を助けてください。