我有一个带有列表视图的片段来显示我的列表内容。我通过另一个片段 - 对话框片段（使用内容提供者的删除和更新方法）更新和删除此列表中的项目，除了列表视图的“实时”刷新之外，一切正常。
我知道我应该在某个地方的适配器上调用 notifyDataSetChanged 但不知道在哪里。
由于用户通过不同的片段删除/更新，所以我猜我应该通过这个片段以某种方式调用适配器上的 notifyDataSetChanged。我也调查了一下，我知道我应该在 UI 线程上运行它。
我尝试了几件事都没有成功。请看一下我的代码。 这是包含 ListView 的片段：
public class ShiftsFragment extends android.app.Fragment implements
LoaderCallbacks<Cursor> {
private Typeface tf, roboto;
private ContentResolver cr;
public shiftsAdapter sa = null;
public static ShiftsDialog sd = null;
public static ShiftsFragment newInstance(String title) {
ShiftsFragment pageFragment = new ShiftsFragment();
return pageFragment;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setHasOptionsMenu(true);
}
@Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
cr = getActivity().getBaseContext().getContentResolver();
getLoaderManager().initLoader(0, null, this);
}
@Override
public void onResume() {
super.onResume();
getLoaderManager().restartLoader(0, null, this);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.shifts, container, false);
roboto = Typeface.createFromAsset(getActivity().getAssets(),
"fonts/JuraLight.ttf");
tf = Typeface.createFromAsset(getActivity().getAssets(),
"fonts/Advert.ttf");
ListView ls = (ListView) view.findViewById(android.R.id.list);
sa = new shiftsAdapter(getActivity().getBaseContext(), null, 0);
ls.setAdapter(sa);
ls.setOnItemLongClickListener(new OnItemLongClickListener() {
@Override
public boolean onItemLongClick(AdapterView<?> arg0, View arg1,
int lineNum, long arg3) {
sd = new ShiftsDialog();
sd.newInstnace(arg3);
sd.show(getFragmentManager(), "shifts_dialog");
return false;
}
});
return view;
}
@Override
public Loader<Cursor> onCreateLoader(int id, Bundle args) {
CursorLoader loader = new CursorLoader(getActivity()
.getApplicationContext(), MyProvider.SHIFTS_URI, null, null,
null, null);
return loader;
}
@Override
public void onLoadFinished(Loader<Cursor> arg0, Cursor cursor) {
sa.swapCursor(cursor);
Log.i("Shifts Numbers", "" + cursor.getCount());
}
@Override
public void onLoaderReset(Loader<Cursor> arg0) {
}
}
这是我根据用户单击的按钮更新/删除的对话框片段：
public class ShiftsDialog extends DialogFragment {
private Typeface roboto;
private static long position = 0;
private ContentResolver cr = null;
public static ShiftsDialog newInstnace(long i) {
position = i;
ShiftsDialog dial = new ShiftsDialog();
return dial;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
cr = getActivity().getBaseContext().getContentResolver();
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
getDialog().getWindow().requestFeature(Window.FEATURE_NO_TITLE);
getDialog().getWindow().setBackgroundDrawable(new ColorDrawable(0));
roboto = Typeface.createFromAsset(getActivity().getAssets(),
"fonts/JuraLight.ttf");
View view = inflater.inflate(R.layout.dialog, container, false);
TextView tv = (TextView) view.findViewById(R.id.options);
tv.setTypeface(roboto);
Button delete = (Button) view.findViewById(R.id.deleteBtn);
delete.setTypeface(roboto);
// OnClick listener for delete function
delete.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// Complete it in the official way
String where = String.valueOf(position);
Uri rowURI = ContentUris.withAppendedId(MyProvider.SHIFTS_URI, position);
cr.delete(rowURI, null, null);
}
});
Button edit = (Button) view.findViewById(R.id.editBtn);
edit.setTypeface(roboto);
// OnClick listener for editing a shift
edit.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
EditDate_Dialog ed = new EditDate_Dialog();
ed.newInstnace(position);
ed.show(getFragmentManager(), "edit_dialog");
dismiss();
}
});
return view;
}
}
我的 ContentProiver 的删除和更新方法（为简洁起见省略其余代码）：
@Override
public int delete(Uri uri, String selection, String[] selectionArgs) {
SQLiteDatabase db = helper.getWritableDatabase();
Log.d("URI", uri.toString());
switch (uriMatcher.match(uri)) {
case SINGLE_ROW:
String rowID = uri.getPathSegments().get(1);
selection = KEY_ID
+ "="
+ rowID
+ (!TextUtils.isEmpty(selection) ? " AND (" + selection
+ ')' : "");
default:
break;
}
if (selection == null)
selection = "1";
// Execute the deletion.
int deleteCount = db.delete(helper.DATABASE_TABLE, selection,
selectionArgs);
Log.d("DeleteCount", "" + deleteCount);
Log.i("Selection", "" + selection);
getContext().getContentResolver().notifyChange(uri, null);
return deleteCount;
}
@Override
public int update(Uri uri, ContentValues values, String selection,
String[] selectionArgs) {
SQLiteDatabase db = helper.getWritableDatabase();
switch (uriMatcher.match(uri)) {
case SINGLE_ROW:
String rowID = uri.getPathSegments().get(1);
selection = KEY_ID
+ "="
+ rowID
+ (!TextUtils.isEmpty(selection) ? " AND (" + selection
+ ')' : "");
default:
break;
}
int updateCount = db.update(helper.DATABASE_TABLE, values, selection,
selectionArgs);
Log.d("Updated", "" + updateCount);
getContext().getContentResolver().notifyChange(uri, null);
return updateCount;
}