目前我有一个包含列表视图的片段。它有一个Add按钮，它将生成一个自定义对话框片段，用户可以在其中输入一个字符串。
当通过ok按钮关闭对话框时，listview应自动更新以包含新输入。
截至目前，我必须单击添加按钮，我可以在对话框后面的背景中看到列表已更新。因此，只有在再次单击添加按钮后才会填充列表。我试图以某种方式从对话框填充列表视图，但没有任何工作。 Notifydatasetchanged（）没有用，而且changeCursor（游标）也没有用。
我认为这就是问题所在。
addButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
addButtonPressed();
testToast();
myDb.insertRow(name,Integer.toString(time));
populateListViewFromDB(rootView);
Toast.makeText(getActivity().getApplicationContext(), "Updated " + name + time + updateListview,
Toast.LENGTH_LONG).show();
}});
public void addButtonPressed(){
FragmentManager fm = getActivity().getSupportFragmentManager();
dialog_foods dialog1 = new dialog_foods();
// dialog1.show(getSupportFragmentManager(), "my_dialog");
//dialog1.show(ft, "acknowledgements");
dialog1.setTargetFragment(this, 0);
//dialog1.show(ft, "acknoledgments");
dialog1.show(fm, "acknowledgements");
//Toast.makeText(getActivity().getApplicationContext(), "Add Button Pressed",
// Toast.LENGTH_LONG).show();
i++;
}
private void populateListViewFromDB(View root){
Cursor cursor = myDb.getAllRows();
//Add others here.
String [] fromFieldNames = new String[] {DBAdapter.KEY_ROWID, DBAdapter.KEY_NAME};
int[] toViewIDs = new int[] {R.id.mMainLabel, R.id.mCityLabel};
SimpleCursorAdapter myCursorAdapter;
myCursorAdapter = new SimpleCursorAdapter(getActivity().getBaseContext(), R.layout.list_cell, cursor, fromFieldNames,toViewIDs,0);
foodsListView = (ListView) root.findViewById(R.id.mFoodListView);
foodsListView.setAdapter(myCursorAdapter);
//myCursorAdapter.notifyDataSetChanged();
myCursorAdapter.changeCursor(cursor);
}
以防我在下面添加了我的其余代码。
这是我的片段，其中包含listview
public class foods_fragment extends Fragment implements dialog_foods.foodsDialogListener {
Button addButton;
Button deleteButton;
int time;
String name;
boolean updateListview = false;
int i;
ListView foodsListView;
//DB Stuff
DBAdapter myDb;
public static foods_fragment newInstance(){
foods_fragment fragment = new foods_fragment();
return fragment;
}
public foods_fragment(){
}
@Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
//outState.putAll();
}
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
final View rootView = inflater.inflate(R.layout.fragment_foods, container, false);
openDB();
populateListViewFromDB(rootView);
foodsListView = (ListView) rootView.findViewById(R.id.mFoodListView);
/*
foodsListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
}
}); */
addButton = (Button)rootView.findViewById(R.id.mAddButton);
deleteButton = (Button)rootView.findViewById(R.id.mDeleteButton);
deleteButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
clearAll(rootView);
}});
addButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
addButtonPressed();
testToast();
myDb.insertRow(name,Integer.toString(time));
populateListViewFromDB(rootView);
Toast.makeText(getActivity().getApplicationContext(), "Updated " + name + time + updateListview,
Toast.LENGTH_LONG).show();
}});
return rootView;
}
public void addButtonPressed(){
FragmentManager fm = getActivity().getSupportFragmentManager();
dialog_foods dialog1 = new dialog_foods();
// dialog1.show(getSupportFragmentManager(), "my_dialog");
//dialog1.show(ft, "acknowledgements");
dialog1.setTargetFragment(this, 0);
//dialog1.show(ft, "acknoledgments");
dialog1.show(fm, "acknowledgements");
//Toast.makeText(getActivity().getApplicationContext(), "Add Button Pressed",
// Toast.LENGTH_LONG).show();
i++;
}
@Override
public void onDestroy() {
super.onDestroy();
closeDB();
}
private void openDB(){
myDb = new DBAdapter(getActivity());
myDb.open();
}
private void closeDB(){
myDb.close();
}
public void clearAll(View root){
myDb.deleteAll();
populateListViewFromDB(root);
}
private void populateListViewFromDB(View root){
Cursor cursor = myDb.getAllRows();
//Add others here.
String [] fromFieldNames = new String[] {DBAdapter.KEY_ROWID, DBAdapter.KEY_NAME};
int[] toViewIDs = new int[] {R.id.mMainLabel, R.id.mCityLabel};
SimpleCursorAdapter myCursorAdapter;
myCursorAdapter = new SimpleCursorAdapter(getActivity().getBaseContext(), R.layout.list_cell, cursor, fromFieldNames,toViewIDs,0);
foodsListView = (ListView) root.findViewById(R.id.mFoodListView);
foodsListView.setAdapter(myCursorAdapter);
//myCursorAdapter.notifyDataSetChanged();
myCursorAdapter.changeCursor(cursor);
}
@Override
public void onAttach(Activity activity) {
super.onAttach(activity);
((MainActivity) activity).onSectionAttached(2);
}
public void testToast(){
// Toast.makeText(getActivity().getApplicationContext(), time + " " + name,
// Toast.LENGTH_LONG).show();
}
@Override
public void nameTimeSubmit(int time, String name, boolean updateListview) {
this.time = time;
this.name = name;
this.updateListview = updateListview;
// View view = getView().findViewById(android.R.id.content);
//populateListViewFromDB(view);
}
}
如果你需要看到这个，我的对话框片段。
public class dialog_foods extends DialogFragment {
private foodsDialogListener callback;
public interface foodsDialogListener{
public void nameTimeSubmit(int time, String name, boolean updateListview);
}
LayoutInflater inflater;
View v;
NumberPicker hour;
NumberPicker min;
NumberPicker sec;
int time;
EditText nameField;
String name;
boolean updateListview = false;
@Override
@NonNull
public Dialog onCreateDialog(Bundle savedInstanceState){
inflater = getActivity().getLayoutInflater();
v = inflater.inflate(R.layout.fragment_add_food, null);
hour = (NumberPicker) v.findViewById(R.id.mHoursNumberPickerFoods);
hour.setMaxValue(24);
hour.setMinValue(0);
hour.setWrapSelectorWheel(true);
min = (NumberPicker) v.findViewById(R.id.mMinutesNumberPickerFoods);
min.setMaxValue(60);
min.setMinValue(0);
min.setWrapSelectorWheel(true);
sec = (NumberPicker) v.findViewById(R.id.mSecondsNumberPickerFoods);
sec.setMaxValue(90);
sec.setMinValue(0);
sec.setWrapSelectorWheel(true);
nameField = (EditText) v.findViewById(R.id.mNameEditText);
try{
callback = (foodsDialogListener) getTargetFragment();
} catch (ClassCastException e){
throw new ClassCastException("calling Fragment must implement onTimeListener");
}
AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
builder.setView(v).setPositiveButton("OK", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
int hours = hour.getValue();
int minutes = min.getValue();
int seconds = sec.getValue();
name = nameField.getText().toString();
time = hours * 3600000 + minutes * 60000 + seconds * 1000;
updateListview = true;
callback.nameTimeSubmit(time, name, updateListview);
/*
MainActivity main;
main = (MainActivity)getActivity();
main.time = time; */
// Toast.makeText(getActivity().getApplicationContext(), "Time: " + time,
// Toast.LENGTH_LONG).show();
}
}).setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
}
});
return builder.create();
}
}