我想从sqlite中删除ListView填充的项目，使用警告对话框onLongClick上的ListView删除该项目
活动：
public class ResultActivity extends ListActivity {
private String selectedItem;
private final Context context = this;
private ArrayAdapter<String> adapter;
Intent intent;
TextView Id;
SaveData controller = new SaveData(this);
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_result);
ArrayList<HashMap<String, String>> hasilList = controller.getAllhasil();
/* jikta tidak kosong, tampilkan data ke ListView
*
*/
if(hasilList.size()!=0) {
ListAdapter adapter = new SimpleAdapter(ResultActivity.this,
hasilList, R.layout.activity_view, new String[] {
"Id", "inggris", "indonesia" }, new int[] {
R.id.Id, R.id.inggris, R.id.indonesia });
setListAdapter(adapter);
ListView lv = getListView();
// Create the listener for long item clicks
// OnItemLongClickListener itemLongListener = new OnItemLongClickListener() {
lv.setOnItemLongClickListener(new OnItemLongClickListener() {
@Override
public boolean onItemLongClick(AdapterView<?> parent, View v, int position, long rowid) {
// Id = (TextView) v.findViewById(R.id.Id);
// String valId = Id.getText().toString();
// Store selected item in global variable
selectedItem = parent.getItemAtPosition(position).toString();
AlertDialog.Builder builder = new AlertDialog.Builder(context);
builder.setMessage("Yakin Hapus " + selectedItem + "?");
builder.setCancelable(false);
builder.setPositiveButton("Ya", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
controller.deletehasil(selectedItem);
controller.getAllhasil();
// adapter.remove(selectedItem);
// adapter.notifyDataSetChanged();
Toast.makeText(
getApplicationContext(),
selectedItem + " Sudah Di Hapus.",
Toast.LENGTH_SHORT).show();
}
});
builder.setNegativeButton("Tidak", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
// Create and show the dialog
builder.show();
// Signal OK to avoid further processing of the long click
return true;
}
});
}
}
@Override
public void onBackPressed() {
super.onBackPressed();
overridePendingTransition(R.anim.fadein, R.anim.fadeout);
}
}
dbhelper：
public class SaveData extends SQLiteOpenHelper {
private static final String LOGCAT = null;
public SaveData(Context applicationcontext) {
super(applicationcontext, "hasil.db", null, 1);
Log.d(LOGCAT,"Created");
}
@Override
public void onCreate(SQLiteDatabase database) {
String query;
query = "CREATE TABLE hasil ( Id INTEGER PRIMARY KEY," +
" inggris TEXT,indonesia TEXT)";
database.execSQL(query);
Log.d(LOGCAT,"hasil Created");
}
@Override
public void onUpgrade(SQLiteDatabase database, int version_old, int current_version) {
String query;
query = "DROP TABLE IF EXISTS hasil";
database.execSQL(query);
onCreate(database);
}
public void addhasil(HashMap<String, String> queryValues) {
SQLiteDatabase database = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put("inggris", queryValues.get("inggris"));
values.put("indonesia", queryValues.get("indonesia"));
database.insert("hasil", null, values);
database.close();
}
public void deletehasil(String id) {
Log.d(LOGCAT,"delete");
SQLiteDatabase database = this.getWritableDatabase();
String deleteQuery = "DELETE FROM hasil where Id='"+ id +"'";
Log.d("query",deleteQuery);
database.execSQL(deleteQuery);
}
public ArrayList<HashMap<String, String>> getAllhasil() {
ArrayList<HashMap<String, String>> hasilList;
hasilList = new ArrayList<HashMap<String, String>>();
String selectQuery = "SELECT * FROM hasil";
SQLiteDatabase database = this.getWritableDatabase();
Cursor cursor = database.rawQuery(selectQuery, null);
if (cursor.moveToFirst()) {
do {
HashMap<String, String> map = new HashMap<String, String>();
map.put("Id", cursor.getString(0));
map.put("inggris", cursor.getString(1));
map.put("indonesia", cursor.getString(2));
hasilList.add(map);
} while (cursor.moveToNext());
}
// return contact list
return hasilList;
}
}
答案 0 :(得分：0)
请查看以下longclick侦听器代码，其中有可删除元素注释的代码。
lv.setOnItemLongClickListener(new OnItemLongClickListener() {
@Override
public boolean onItemLongClick(AdapterView<?> parent, View v, final int position, long rowid) {
// Id = (TextView) v.findViewById(R.id.Id);
// String valId = Id.getText().toString();
// Store selected item in global variable
selectedItem = parent.getItemAtPosition(position).toString();
AlertDialog.Builder builder = new AlertDialog.Builder(context);
builder.setMessage("Yakin Hapus " + selectedItem + "?");
builder.setCancelable(false);
builder.setPositiveButton("Ya", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
controller.deletehasil(selectedItem);
controller.getAllhasil();
//------------Code to remove element-----------
hasilList.remove(position);
adapter.notifyDataSetChanged();
//-------------xxxxxxxxxxxxx-------------
Toast.makeText(
getApplicationContext(),
selectedItem + " Sudah Di Hapus.",
Toast.LENGTH_SHORT).show();
}
});
builder.setNegativeButton("Tidak", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
// Create and show the dialog
builder.show();
// Signal OK to avoid further processing of the long click
return true;
}
});