0
任何人都可以告诉我如何通过长时间点击它从SQLite数据库和列表视图中删除内容？另外，我是否只需要从SQLite数据库或SQLite数据库和listview中删除内容？通过长时间点击listview从SQLite和列表视图中删除其内容点击
这里是我的项目类：
数据库帮助
public class DatabaseHelper extends SQLiteOpenHelper {
private static final int DATABASE_VERSION = 3;
private static final String DATABASE_NAME = "products.db";
private static final String TABLE_NAME = "products";
private static final String COLUMN_ID = "_id";
private static final String MARKET = "market";
private static final String PRODUCT = "product";
private SQLiteDatabase db;
public DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL("CREATE TABLE " + TABLE_NAME + "("
+ COLUMN_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, "
+ MARKET + " TEXT, "
+ PRODUCT + " TEXT)");
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME + "");
onCreate(db);
}
public Cursor getRecords() {
db = getReadableDatabase();
return db.rawQuery(
"SELECT * FROM " + TABLE_NAME,
null);
}
public void addRecords(String market, String product) {
db = getWritableDatabase();
ContentValues contentValues = new ContentValues();
contentValues.put(MARKET, market);
contentValues.put(PRODUCT, product);
db.insert(TABLE_NAME, null, contentValues);
db.close();
}
public void deleteRecords(int id){
}}
MainActivity
public class MainActivity extends AppCompatActivity {
ListView lv;
DatabaseHelper databaseHelper;
ShoppingCartAdapter shoppingCartAdapter;
private static final int TIME_ENTRY_REQUEST_CODE = 1;
Cursor cursor;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
lv = (ListView) findViewById(R.id.list_view_main);
databaseHelper = new DatabaseHelper(this);
ListView listView = (ListView) findViewById(R.id.list_view_main);
shoppingCartAdapter = new ShoppingCartAdapter(this, databaseHelper.getRecords(), CursorAdapter.FLAG_REGISTER_CONTENT_OBSERVER);
listView.setAdapter(shoppingCartAdapter);
lv.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
@Override
public boolean onItemLongClick(final AdapterView<?> parent, View view, int position, long id) {
final int pos = position;
AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
builder.setTitle("Are you sure you want to delete?");
builder.setPositiveButton("DELETE", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
}
});
builder.setNegativeButton("CANCEL", null);
builder.show();
return true;
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
super.onCreateOptionsMenu(menu);
MenuInflater menuInflater = getMenuInflater();
menuInflater.inflate(R.menu.menu_template, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
if (item.getItemId() == R.id.menu_add_id) {
Intent intent = new Intent(this, AddContentActivity.class);
startActivityForResult(intent, TIME_ENTRY_REQUEST_CODE);
return true;
}
return super.onOptionsItemSelected(item);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == TIME_ENTRY_REQUEST_CODE) {
if (resultCode == RESULT_OK) {
String market = data.getStringExtra("market");
String product = data.getStringExtra("product");
databaseHelper.addRecords(market, product);
shoppingCartAdapter.changeCursor(databaseHelper.getRecords());
}
}
}
}
AddContentActivity
public class AddContentActivity extends AppCompatActivity{
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_addcontent);
}
public void onAddButton(View view){
Intent intent = getIntent();
EditText marketet = (EditText) findViewById(R.id.marketet_id);
EditText productet = (EditText) findViewById(R.id.productet_id);
intent.putExtra("market", marketet.getText().toString());
intent.putExtra("product", productet.getText().toString());
this.setResult(RESULT_OK, intent);
finish();
}
}
ShoppingCartAdapter
public class ShoppingCartAdapter extends CursorAdapter{
public ShoppingCartAdapter(Context context, Cursor cursor, int flags){
super(context, cursor, flags);
}
@Override
public void bindView(View view, Context context, Cursor cursor) {
TextView marketTv = (TextView) view.findViewById(R.id.markettv_id);
TextView productTv = (TextView) view.findViewById(R.id.producttv_id);
marketTv.setText(cursor.getString(1));
productTv.setText(cursor.getString(2));
}
@Override
public View newView(Context context, Cursor cursor, ViewGroup parent) {
LayoutInflater inflater = LayoutInflater.from(parent.getContext());
View view = inflater.inflate(R.layout.list_view_template, parent, false);
return view;
}
}