僑光科技大學 蔡存孝老師 解說參考：http://rs2.ocu.edu.tw/~tsay/files/TQC204.pdf
GDD02.java - Activity主體
package COM.TQC.GDD02;
import android.app.Activity;
import android.database.Cursor;
import android.database.sqlite.SQLiteCursor;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.SimpleCursorAdapter;
public class GDD02 extends Activity
{
private mySQLiteOpenHelper gaaSQLiteOpenHelper;
private Cursor myCursor;
private ListView myListView;
private EditText myEditText;
private int _id;
protected final static int MENU_ADD = Menu.FIRST;
protected final static int MENU_EDIT = Menu.FIRST + 1;
protected final static int MENU_DELETE = Menu.FIRST + 2;
@Override
public boolean onOptionsItemSelected(MenuItem item)
{
super.onOptionsItemSelected(item);
switch (item.getItemId())
{
case MENU_ADD:
this.addTodo();
break;
case MENU_EDIT:
this.editTodo();
break;
case MENU_DELETE:
this.deleteTodo();
break;
}
return true;
}
@Override
public boolean onCreateOptionsMenu(Menu menu)
{
super.onCreateOptionsMenu(menu);
//first
menu.add(0, MENU_ADD, 0, getString(R.string.strAddButton));
menu.add(0, MENU_EDIT, 0, getString(R.string.strEditButton));
menu.add(0, MENU_DELETE, 0, getString(R.string.strDeleteButton));
//
return true;
}
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
myListView = (ListView) this.findViewById(R.id.myListView);
myEditText = (EditText) this.findViewById(R.id.myEditText);
gaaSQLiteOpenHelper = new mySQLiteOpenHelper(this);
myCursor = gaaSQLiteOpenHelper.select();
SimpleCursorAdapter adapter = new SimpleCursorAdapter(this, R.layout.list,
myCursor, new String[]
{ gaaSQLiteOpenHelper.FIELD_TEXT }, new int[]
{ R.id.listTextView1 });
myListView.setAdapter(adapter);
myListView.setOnItemClickListener(new AdapterView.OnItemClickListener()
{
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
long arg3)
{
myCursor.moveToPosition(arg2);
_id = myCursor.getInt(0);
myEditText.setText(myCursor.getString(1));
}
});
}
private void addTodo()
{
//second call gaaSQLiteOpenHelper SQL insert method
gaaSQLiteOpenHelper.insert(myEditText.getText().toString());
myCursor.requery();
//
}
private void editTodo()
{
//second call gaaSQLiteOpenHelper SQL update method
gaaSQLiteOpenHelper.update(_id, myEditText.getText().toString());
myCursor.requery();
//
}
private void deleteTodo()
{
//second call gaaSQLiteOpenHelper SQL delete method
gaaSQLiteOpenHelper.delete(_id);
myCursor.requery();
//
}
}
mySQLiteOpenHelper
package COM.TQC.GDD02;
import java.nio.charset.CodingErrorAction;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
public class mySQLiteOpenHelper extends SQLiteOpenHelper
{
private final static String DATABASE_NAME = "todo_db";
private final static int DATABASE_VERSION = 1;
private final static String TABLE_NAME = "todo_table";
public final static String FIELD_id = "_id";
public final static String FIELD_TEXT = "todo_text";
public mySQLiteOpenHelper(Context context)
{
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db)
{
String sql = "CREATE TABLE " + TABLE_NAME + " (" + FIELD_id
+ " INTEGER primary key autoincrement, " + " " + FIELD_TEXT + " text)";
db.execSQL(sql);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion)
{
String sql = "DROP TABLE IF EXISTS " + TABLE_NAME;
db.execSQL(sql);
onCreate(db);
}
public Cursor select()
{
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.query(TABLE_NAME, null, null, null, null, null, null);
return cursor;
}
public void insert(String text)
{
SQLiteDatabase db = this.getWritableDatabase();
// add date
ContentValues cv = new ContentValues();
cv.put(FIELD_TEXT, text);
db.insert(TABLE_NAME, null, cv);
//
}
public void delete(int id)
{
SQLiteDatabase db = this.getWritableDatabase();
//
String where = FIELD_id + " = " + id;
// delete date
db.delete(TABLE_NAME, where, null);
//
}
public void update(int id, String text)
{
SQLiteDatabase db = this.getWritableDatabase();
//
String where = FIELD_id + " = " + id;
// update date
ContentValues cv = new ContentValues();
cv.put(FIELD_TEXT, text);
db.update(TABLE_NAME, cv, where, null);
//
}
}
以下圖片為android程式建立的database所在位置
