android - ExpandableListView - 更新或删除特定行而不调用 Activity 中的适配器
问题描述
从数据库中获取数据后,我实现了一个可扩展列表视图。数据在列表中正确出现,子项目详细信息页面上的 onClicking() 正在打开,用户可以在其中删除数据并编辑数据。但是再次返回 MainActivity 后,我必须调用 OnResume 中的 Adpater 类来重新加载我不想要的数据。我只想删除或显示更新的数据。我已经尝试过notifyDataSetChanged()但它没有用,可能是我在错误的地方使用它。请指导我一点......
适配器类..
public class TransExpAdapter extends BaseExpandableListAdapter {
private Context context;
List<ExcelDataModel> list_shareofshelf;
public TransExpAdapter(Context context, List<ExcelDataModel> list_shareofshelf) {
this.context = context;
this.list_shareofshelf = list_shareofshelf;
}
@Override
public Object getChild(int listPosition, int expandedListPosition) {
return this.list_shareofshelf.get(listPosition);
}
@Override
public long getChildId(int listPosition, int expandedListPosition) {
return expandedListPosition;
}
@Override
public View getChildView(final int listPosition, final int expandedListPosition, boolean isLastChild, View convertView, ViewGroup parent) {
LayoutInflater layoutInflater = (LayoutInflater) this.context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View cview = layoutInflater.inflate(R.layout.list_child_sos, null);
RelativeLayout child_container = cview.findViewById(R.id.child_container);
TextView tv_category = cview.findViewById(R.id.tv_category);
TextView tv_expense = cview.findViewById(R.id.tv_expense);
ImageView iv_icon = cview.findViewById(R.id.iv_icon);
try {
if (list_shareofshelf.get(listPosition).getGroupFocAll().get(expandedListPosition).getIcon_name() != null &&
!list_shareofshelf.get(listPosition).getGroupFocAll().get(expandedListPosition).getIcon_name().isEmpty()) {
int imageid = context.getResources().getIdentifier(list_shareofshelf.get(listPosition).getGroupFocAll().get(expandedListPosition).getIcon_name(), "drawable", context.getPackageName());
iv_icon.setImageResource(imageid);
} else {
iv_icon.setImageResource(R.drawable.ic_gray_no_img);
}
} catch (Exception e) {
iv_icon.setImageResource(R.drawable.ic_gray_no_img);
}
if (list_shareofshelf.get(listPosition).getGroupFocAll().get(expandedListPosition).getIncome_Expenses().equalsIgnoreCase("Expenses")) {
tv_expense.setText("-" + list_shareofshelf.get(listPosition).getGroupFocAll().get(expandedListPosition).getAmount());
} else {
tv_expense.setText(list_shareofshelf.get(listPosition).getGroupFocAll().get(expandedListPosition).getAmount());
}
child_container.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (!list_shareofshelf.get(listPosition).getGroupFocAll().get(expandedListPosition).getId().isEmpty()) {
Intent i = new Intent(context, ExpenseDetails.class);
i.putExtra("trans_id", list_shareofshelf.get(listPosition).getGroupFocAll().get(expandedListPosition).getId());
context.startActivity(i);
}
}
});
if (!list_shareofshelf.get(listPosition).getGroupFocAll().get(expandedListPosition).getMemo().isEmpty()) {
tv_category.setText(list_shareofshelf.get(listPosition).getGroupFocAll().get(expandedListPosition).getMemo());
} else {
tv_category.setText(list_shareofshelf.get(listPosition).getGroupFocAll().get(expandedListPosition).getCategory());
}
if (expandedListPosition == list_shareofshelf.get(listPosition).getGroupFocAll().size() - 1) {
child_container.setBackgroundResource(R.drawable.card_bottom_round);
}
return cview;
}
@Override
public int getChildrenCount(int listPosition) {
return list_shareofshelf.get(listPosition).getGroupFocAll().size();
}
@Override
public Object getGroup(int listPosition) {
return list_shareofshelf.get(listPosition).getGroupFocAll();
}
@Override
public int getGroupCount() {
return list_shareofshelf.size();
}
@Override
public long getGroupId(int listPosition) {
return listPosition;
}
@Override
public View getGroupView(int listPosition, boolean isExpanded, View convertView, ViewGroup parent) {
LayoutInflater layoutInflater = (LayoutInflater) this.context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View view = layoutInflater.inflate(R.layout.list_parent_sos, null);
ExpandableListView eLV = (ExpandableListView) parent;
eLV.expandGroup(listPosition);
TextView listTitleTextView = view.findViewById(R.id.listTitle);
TextView tv_expenditures = view.findViewById(R.id.tv_expenditures);
listTitleTextView.setText(Utils.getFormattedDate(list_shareofshelf.get(listPosition).getDate()));
tv_expenditures.setText("Expenses: " + list_shareofshelf.get(listPosition).getExp_amt_() + " Income: " + list_shareofshelf.get(listPosition).getInc_amt_());
return view;
}
@Override
public boolean hasStableIds() {
return false;
}
@Override
public boolean isChildSelectable(int listPosition, int expandedListPosition) {
return true;
}
@Override
public void registerDataSetObserver(DataSetObserver observer) {
super.registerDataSetObserver(observer);
}
}
MainActivity 调用...
private class AsyncTaskGetTransactionData extends AsyncTask<Void, Void, Void> {
@Override
protected Void doInBackground(Void... voids) {
list_final_transaction_data = db.getTransactionDetails(current_month);
return null;
}
@Override
protected void onPreExecute() {
super.onPreExecute();
}
@Override
protected void onPostExecute(Void aVoid) {
super.onPostExecute(aVoid);
if (list_final_transaction_data.size() > 0) {
expandableListAdapter = new TransExpAdapter(context, list_final_transaction_data);
expandableListView.setAdapter(expandableListAdapter);
expandableListView.setVisibility(View.VISIBLE);
new AsyncTaskSummationExpenses().execute();
} else {
tv_income.setText("0");
tv_expenses.setText("0");
tv_balance.setText("0");
p.dismiss();
expandableListView.setVisibility(View.GONE);
}
}
}
////数据库方法
public List<ExcelDataModel> getTransactionDetails(String current_month) {
List<ExcelDataModel> listProd = new ArrayList<>();
Log.d("CurrentMonthDB", current_month);
SQLiteDatabase db = this.getWritableDatabase();
try {
String selectQuery = "select f.date,(select sum(amount) from tbl_transactions WHERE trans_type='Expenses' and date=f.date)exp, " +
"(select sum(amount) from tbl_transactions where trans_type='Income' and date=f.date)inc from tbl_transactions f where f.date like '%" + current_month + "%' GROUP by f.date ORDER BY strftime('%s', f.date) desc";
Log.d("FirstQuery", selectQuery);
Cursor c = db.rawQuery(selectQuery, null);
if (c.moveToFirst()) {
do {
ExcelDataModel foc_cat = new ExcelDataModel();
String date = c.getString(c.getColumnIndex("date"));
String income = c.getString(c.getColumnIndex("inc"));
String expense = c.getString(c.getColumnIndex("exp"));
String selectQuery1 = "select * from tbl_transactions a LEFT join tbl_category b where a.cat_id=b.cat_id and date='" + date + "' order by memo asc";
Log.d("SecondQuery", selectQuery1);
Cursor cursor2 = db.rawQuery(selectQuery1, null);
if (cursor2.moveToFirst()) {
List<ExcelDataModel> subCat_list = new ArrayList<>();
// ExcelDataModel pp_dummy = new ExcelDataModel();
//pp_dummy.setId("");
// subCat_list.add(pp_dummy);
do {
ExcelDataModel prod_subcat = new ExcelDataModel();
prod_subcat.setDate(cursor2.getString(cursor2.getColumnIndex("date")));
prod_subcat.setIncome_Expenses(cursor2.getString(cursor2.getColumnIndex("trans_type")));
prod_subcat.setCategory(cursor2.getString(cursor2.getColumnIndex("cat_name")));
prod_subcat.setMemo(cursor2.getString(cursor2.getColumnIndex("memo")));
prod_subcat.setAmount(cursor2.getString(cursor2.getColumnIndex("amount")));
prod_subcat.setId(cursor2.getString(cursor2.getColumnIndex("trans_id")));
prod_subcat.setIcon_name(cursor2.getString(cursor2.getColumnIndex("cat_iconname")));
subCat_list.add(prod_subcat);
} while (cursor2.moveToNext());
foc_cat.setDate(date);
if (expense != null) {
foc_cat.setExp_amt_(Double.parseDouble(expense));
} else {
foc_cat.setExp_amt_(0);
}
if (income != null) {
foc_cat.setInc_amt_(Double.parseDouble(income));
} else {
foc_cat.setInc_amt_(0);
}
foc_cat.setDate(date);
foc_cat.setGroupFocAll(subCat_list);
listProd.add(foc_cat);
cursor2.close();
}
} while (c.moveToNext());
}
c.close();
db.close();
} catch (Exception e) {
e.printStackTrace();
} finally {
if (db != null)
db.close();
}
return listProd;
}
解决方案
尝试OnClick()
在孩子的 上使用回调并在活动中捕获该回调,这样您就可以做startActivityForResult()
而不仅仅是startActivity()
.
这样,您就可以知道用户何时删除了详细信息活动中的某些内容,就在该活动被销毁之后。然后,在onActivityResult
你做yourAdapter.notifyDataSetChanged();
像这样,在适配器中:
child_container.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (!list_shareofshelf.get(listPosition).getGroupFocAll().get(expandedListPosition).getId().isEmpty()) {
callback.childClicked(list_shareofshelf.get(listPosition).getGroupFocAll().get(expandedListPosition).getId());
}
}
});
然后,在您的活动中,您实现回调
@Override
public void childClicked(int id){
Intent i = new Intent(context, ExpenseDetails.class);
i.putExtra("trans_id", id);
startActivityForResult(i, yourRequestCode);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, @Nullable
Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == yourRequestCode) {
if (resultCode == RESULT_DELETED) {
adapter.notifyDataSetChanged();
}
}
}
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