我正在尝试从listView和数据库中删除项目，但我无法应对。我抛出代码，我希望能提供帮助。我在屏幕上抛出showList的代码并保存到数据库sqlite。任何的想法？我也是初学者，任何帮助将不胜感激。我正在寻找教程，删除对我不起作用。我不知道为什么。如何在退出申请后清除我的清单？因为当我转到应用程序时，listView中的数据仍然可见。
public class PropertyListAdapter extends BaseAdapter {
Context context;
ArrayList<Property> propertyList;
public PropertyListAdapter(Context context, ArrayList<Property> list) {
this.context = context;
propertyList = list;
}
@Override
public int getCount() {
return propertyList.size();
}
@Override
public Object getItem(int position) {
return propertyList.get(position);
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(final int position, View convertView, ViewGroup arg2) {
View vi = convertView;
Property propertyListItems = propertyList.get(position);
if (convertView == null) {
LayoutInflater inflater = (LayoutInflater) context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
vi = inflater.inflate(R.layout.property_list_row, null);
}
TextView tvSlNo = (TextView) convertView.findViewById(R.id.tv_slno);
tvSlNo.setText(String.valueOf(propertyListItems.getId()));
TextView tvName1 = (TextView) convertView.findViewById(R.id.tv_name1);
tvName1.setText(propertyListItems.getType());
TextView tvName = (TextView) convertView.findViewById(R.id.tv_name);
tvName.setText(propertyListItems.getAddress());
TextView tvPhone = (TextView) convertView.findViewById(R.id.tv_phone);
tvPhone.setText(String.valueOf(propertyListItems.getValue()));
TextView tvPhone1 = (TextView) convertView.findViewById(R.id.tv_phone1);
tvPhone1.setText(String.valueOf(propertyListItems.getDebt()));
TextView tvName2 = (TextView) convertView.findViewById(R.id.tv_name2);
tvName2.setText(propertyListItems.getNotes());
Button deletePropertyItem = (Button) vi.findViewById(R.id.DeletePropertyListItem);
deletePropertyItem.setTag(position);
deletePropertyItem.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Integer index = (Integer)v.getTag();
propertyList.remove(position);
notifyDataSetChanged();
}
});
return vi;
}
db = new MeetingsDataBaseHelper(this);
showList();
add1.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Double value1, debt;
String editValueDb1,editDebtDb1;
final Integer idEncounterToPass = AppMainScreen.getMeetingListClickedItem().getEncounter_id();
String type = editTextTypeProperty.getText().toString();
String address = editAddresse1.getText().toString();
// Double value1 = Double.valueOf(editValue1.getText().toString());
String editValue1String = ReportMainScreen.editValue1.getText().toString();
if (editValue1String.length() > 0)
{
value1 = Double.valueOf(editValue1String);
} else {
value1 = Double.valueOf("0.00");
}
// Double debt = editViewDebt1.getText().toString();
String editDebtString = ReportMainScreen.editViewDebt1.getText().toString();
if (editDebtString.length() > 0)
{
debt = Double.valueOf(editDebtString);
} else {
debt = Double.valueOf("0.00");
}
String notes = editNotesProperty.getText().toString();
String encounter_id = String.valueOf(idEncounterToPass);
String posted = "0";
String query = "INSERT INTO property(type,address,value,debt,notes,encounter_id,posted) values ('"
+ type + "','" + address + "','" + value1 + "','" + debt + "','" + notes + "','" + encounter_id + "','" + posted + "')";
db.executeQuery(query);
showList();
editTextTypeProperty.setText("");
editAddresse1.setText("");
editValue1.setText("");
editViewDebt1.setText("");
editNotesProperty.setText("");
}
});
private void showList() {
ArrayList<Property> propertyList = new ArrayList<Property>();
propertyList.clear();
String query = "SELECT * FROM property ";
Cursor c1 = db.selectQuery(query);
if (c1 != null && c1.getCount() != 0) {
if (c1.moveToFirst()) {
do {
Property propertyListItems = new Property();
propertyListItems.setId(Integer.valueOf(c1.getString(c1.getColumnIndex("id"))));
propertyListItems.setType(c1.getString(c1.getColumnIndex("type")));
propertyListItems.setAddress(c1.getString(c1.getColumnIndex("address")));
propertyListItems.setValue(Double.valueOf(c1.getString(c1.getColumnIndex("value"))));
propertyListItems.setDebt(Double.valueOf(c1.getString(c1.getColumnIndex("debt"))));
propertyListItems.setNotes(c1.getString(c1.getColumnIndex("notes")));
propertyList.add(propertyListItems);
} while (c1.moveToNext());
}
}
c1.close();
PropertyListAdapter propertyListAdapter = new PropertyListAdapter(ReportMainScreen.this, propertyList);
first_list_view.setAdapter(propertyListAdapter);
propertyListAdapter.notifyDataSetChanged(); // TODO check this reg. clearing subtables
// propertyList.remove(propertyListAdapter);
}
答案 0 :(得分：0)
删除db
private void DeleteItemFormList() {
Property property = new Property();
ArrayList<Property> propertyList = new ArrayList<Property>();
propertyList.clear();
int id = property.getId();
String delQuery = "DELETE FROM Property WHERE id='"+id+"' ";
db.executeQuery(delQuery);
showList();
PropertyListAdapter propertyListAdapter = new PropertyListAdapter(ReportMainScreen.this, propertyList);
first_list_view.setAdapter(propertyListAdapter);
propertyListAdapter.notifyDataSetChanged(); // TODO check this reg. clearing subtables
// propertyList.remove(propertyListAdapter);
}
答案 1 :(得分：0)
我认为你需要传递自动递增而不是位置的ID。int index=propertyList.get(position).get(Id);
Button deletePropertyItem = (Button) vi.findViewById(R.id.DeletePropertyListItem);
deletePropertyItem.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
propertyList.remove(index);
notifyDataSetChanged();
}
});