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Uczę się prototypowania w Android Studio i dotarłem do przeszkody, na którą nie mogę znaleźć odpowiedzi.Dodanie do fragmentu ArrayAdapter z Activity AlertDialog
Mam działanie, które wyświetla niestandardowy ArrayAdapter jako ListView. Mogę edytować elementy w ListView, klikając je i wpisując w wynik AlertDialog. Jest też przycisk dodawania, który mogę nacisnąć, i wywołuje podobny AlertDialog, ale kiedy klikam, nic nie zostanie dodane do ListView. Jak uzyskać dane wejściowe tekstu AlertDialog do zapisania jako nowy element ArrayAdapter?
Większość znalezionych przeze mnie przykładów utworzyło ArrayAdapter bezpośrednio w Aktywności, a nie w Fragmentie tak, jak to zrobiłem.
MainActivity.java
public class MainActivity extends AppCompatActivity {
private static final String TAG = "MainActivity";
@Override
protected void onCreate(Bundle savedInstanceState) { //initialize the activity
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main); //establish where the layout will come from
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar); //creates a toolbar
setSupportActionBar(toolbar);
if (findViewById(R.id.fragment_container) != null) {
if (savedInstanceState != null) {
return;
}
//creates the first fragment dynamically, so it can be replaced
Fragment firstFragment = new MainActivityFragment();
firstFragment.setArguments(getIntent().getExtras());
getSupportFragmentManager().beginTransaction()
.add(R.id.fragment_container, firstFragment).commit();
}
//This creates the Floating Action Button
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
createDialog();
}
private void createDialog() {
ArrayList<User> users = new ArrayList<User>();
// create an AlertDialog that'll come up when the add button is clicked
AlertDialog.Builder alertDialog = new AlertDialog.Builder(MainActivity.this);
// set title
alertDialog.setTitle("Add item");
final EditText input = new EditText(MainActivity.this); //uses the EditText from dialog_set
input.setInputType(InputType.TYPE_CLASS_TEXT); //makes the dialog ask for plain text input
alertDialog.setView(input);
// set up buttons
alertDialog.setPositiveButton("Save", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
String textInput = input.getText().toString(); //saves user text as a string
Log.d(TAG, textInput); // records input as a log
CustomUsersAdapter.this.add(textInput);
}
});
alertDialog.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
// show it
alertDialog.show();
}
});
}
MainActivityFragment.java
public class MainActivityFragment extends Fragment {
@BindView(R.id.lvUsers) ListView listView;
public MainActivityFragment() {
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_main, container, false);
ButterKnife.bind(this, view);
ArrayList<User> arrayOfUsers = new ArrayList<User>();
arrayOfUsers.add(new User("Person 1", "Hometown 1"));
arrayOfUsers.add(new User("Person 2", "Hometown 2"));
arrayOfUsers.add(new User("Person 3", "Hometown 3"));
arrayOfUsers.add(new User("Person 4", "Hometown 4"));
arrayOfUsers.add(new User("Person 5", "Hometown 5"));
// Create the adapter to convert the array to views
CustomUsersAdapter adapter = new CustomUsersAdapter(getContext(), arrayOfUsers);
// Attach the adapter to a ListView
listView.setAdapter(adapter);
return view;
}
CustomUsersAdapter.java
public class CustomUsersAdapter extends ArrayAdapter<User> {
private ArrayList<User> users;
public CustomUsersAdapter(Context context, ArrayList<User> users) {
super(context, 0, users);
this.users = users;
}
@Override
public View getView(final int position, View convertView, ViewGroup parent) {
// Get the data item for this position
User user = getItem(position);
// Check if an existing view is being reused, otherwise inflate the view
if (convertView == null) {
convertView = LayoutInflater.from(getContext()).inflate(R.layout.item_user, parent, false);
}
// Lookup view for data population
TextView tvName = (TextView) convertView.findViewById(R.id.tvName);
TextView tvHome = (TextView) convertView.findViewById(R.id.tvHometown);
// Populate the data into the template view using the data object
tvName.setText(user.name);
tvHome.setText(user.hometown);
convertView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
createDialog(position);
}
});
// Return the completed view to render on screen
return convertView;
}
protected void add(String textInput) {
add(new User(textInput, "Incomplete"));
}
private void createDialog(final int position) {
// create an AlertDialog that'll come up when text is clicked
AlertDialog.Builder alertDialog = new AlertDialog.Builder(
getContext());
// set title
alertDialog.setTitle("Edit item");
final EditText input = new EditText(getContext()); //uses the EditText from dialog_set
input.setInputType(InputType.TYPE_CLASS_TEXT); //makes the dialog ask for plain text input
alertDialog.setView(input);
// set up buttons
alertDialog.setPositiveButton("Save", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
String textInput = input.getText().toString(); //saves user text as a string
users.get(position).name = textInput;
notifyDataSetChanged();
}
});
alertDialog.setNeutralButton("Complete", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
users.get(position).hometown = "Complete";
notifyDataSetChanged();
}
});
alertDialog.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
// show it
alertDialog.show();
}
układ ListView (z fragment_main.xml)
<ListView
android:id="@+id/lvUsers"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_alignParentRight="true"
android:layout_alignParentTop="true" >
</ListView>
'Mogę edytować elementy w ArrayAdapter klikając je". Niemożliwy. Adapter tablicowy nie jest elementem GUI, nie ma widoku, więc można go skasować. Proszę ponownie sformułować. – greenapps
Czy istnieje powód, dla którego masz funkcjonalność FAB w działaniu w stosunku do fragmentu? – BlackHatSamurai
@greenapps, zmieniłem nieco sformułowanie - czy teraz jest jaśniejsze? – songbird813