ParseUser Username Adapter in Android ListView doesn't show Data

问题

im trying to show the usernames of all the people in my Parse.com User.class in an Android ListView, but it won't show any Data if I execute it.

It runs on my Samsung Galaxy S2 with Android 4.1.2

The Code:

// Create and populate an ArrayList of objects from parse
final ArrayAdapter<String> listAdapter = new ArrayAdapter<String>(this,
        android.R.layout.simple_list_item_1);
final ListView userlist = (ListView) findViewById(android.R.id.list);
userlist.setAdapter(listAdapter);
final ParseQuery query = ParseUser.getQuery();
query.findInBackground(new FindCallback() {
    @Override
    public void done(List userlist, ParseException e) {
        if (e == null) {
            for (int i = 0; i < userlist.size(); i++) {
                ParseUser u = (ParseUser) userlist.get(i);
                String name = u.getString("username");
                listAdapter.add(name);
            }
        }
        else {
            Toast.makeText(getApplicationContext(), "Error", Toast.LENGTH_LONG).show();
        }
    }

    @Override
    public void done(Object o, Throwable throwable) {

    }
});

The XML:

<LinearLayout
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
xmlns:android="http://schemas.android.com/apk/res/android">

    <ListView
        android:id="@android:id/list"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />

</LinearLayout>

And it only shows a white screen and no usernames...

(Do you need the logcat?)

Appreciate help!! `

回答1:

set adapter after cycle

if (e == null) {
     for (int i = 0; i < userlist.size(); i++) {
          ParseUser u = (ParseUser) userlist.get(i);
          String name = u.getString("username");
          listAdapter.add(name);
       }
    userlist.setAdapter(listAdapter);

回答2:

ParseQueryAdapter.QueryFactory<ParseUser> factory;
factory = new ParseQueryAdapter.QueryFactory<ParseUser>() {
        @Override
        public ParseQuery<ParseUser> create() {
            ParseQuery query = new ParseQuery("User");
            return query;
        }
    };
mainAdapter = new ParseQueryAdapter<ParseUser>(this, factory) {
@Override
public View getItemView(final ParseObject user, View v, ViewGroup parent) {
    if (v == null) {
        v = View.inflate(getContext(), R.layout.your_list_view, null);
    }
    return v;
}};

mainAdapter.setPaginationEnabled(true);
mainAdapter.setTextKey("title");
mainAdapter.setImageKey("Image");
mainAdapter.loadObjects();

see if this works

来源：https://stackoverflow.com/questions/32475596/parseuser-username-adapter-in-android-listview-doesnt-show-data

标签

android

listview

parse-platform

android-arrayadapter