parse.com onListItemClick不显示任何详细信息

Question

我正在尝试使用Parse.com获取餐厅名称并将其放入listView的代码。当您单击其中一个名称时，它将带您进入一个详细信息页面，您可以在其中获取有关餐厅的详细信息。问题是当我单击ListView上的名称时，它转到了详细信息页面，但什么也没有显示。我是Android和Parse的新手，不完全了解它应该如何工作。

这是我的Mainactivity中的代码

public class MainActivity extends Activity {

private CustomAdapter urgentTodosAdapter;
private ParseQueryAdapter<ParseObject> mainAdapter;
private ListView listView;
List<ParseObject> Name =new ArrayList<ParseObject>();
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.listview);
    mainAdapter = new ParseQueryAdapter<ParseObject>(this,"RestaurantDetail");
    urgentTodosAdapter = new CustomAdapter(this);
    listView = (ListView) findViewById(R.id.listView1);
    listView.setAdapter(urgentTodosAdapter);
    urgentTodosAdapter.loadObjects();
// Binds the Adapter to the ListView
listView.setAdapter(urgentTodosAdapter);
// Capture button clicks on ListView items
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
    @Override
    public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
        // Send single item click data to SingleItemView Class
        Intent random1 = new Intent(MainActivity.this, SingleItemView.class);
        if (Name.size() > i)
            // Pass data "name" followed by the position
            random1.putExtra("Name", Name.get(i).getString("Name"));
        // Open SingleItemView.java Activity
        startActivity(random1);
    }
});
}
}

和我的CustomAdapter类

public class CustomAdapter extends ParseQueryAdapter<ParseObject> {
public CustomAdapter(Context context) {
    super(context, new ParseQueryAdapter.QueryFactory<ParseObject>() {
        public ParseQuery create() {
            ParseQuery query = new ParseQuery("RestaurantDetail");
  /* query.whereEqualTo("Name", true);*/
            return query;
        }
    });
}
@Override
public View getItemView(ParseObject object, View v, ViewGroup parent) {
    if (v == null) {
        v = View.inflate(getContext(), R.layout.activity_main, null);
    }
    super.getItemView(object, v, parent);
    ParseImageView todoImage = (ParseImageView) v.findViewById(R.id.icon);
    ParseFile imageFile = object.getParseFile("Logo");
    if (imageFile != null) {
        todoImage.setParseFile(imageFile);
        todoImage.loadInBackground();
    }
    TextView titleTextView = (TextView) v.findViewById(R.id.textView3);
    titleTextView.setText(object.getString("Name"));
    return v;
}
}

和应该显示餐厅名称等的班级

@ParseClassName("RestaurantDetail")
public class SingleItemView extends Activity {
// Declare Variables
protected TextView txtname;
String Name;
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    // Get the view from SingleItemView.xml
    setContentView(R.layout.single_item_view);
    txtname = (TextView) findViewById(R.id.name);
    // Retrieve data from MainActivity on item click event
    Intent random1 = getIntent();
    // Get the name
    Name = random1.getStringExtra("Name");
    // Locate the TextView in singleitemview.xml
    // Load the text into the TextView
    txtname.setText(Name);
}
}

Answer 1

请在OP评论部分中查看我的评论以获取某些上下文：

答案：

在您的主动脉中，您没有创建查询以添加到适配器中。在下面查看并根据您的需求调整分区：

MainActivity class

public class MainActivity extends Activity {

private CustomAdapter urgentTodosAdapter;
private ParseQueryAdapter<ParseObject> mainAdapter;
private ListView listView;
List<ParseObject> Name =new ArrayList<ParseObject>();
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.listview);
    listView = (ListView) findViewById(R.id.listView1);
    //I'm not sure how you initialized your custom adapter - i'll show you how i did it, but yours might work too
    urgentTodosAdapter = new urgentTodosAdapter(MainActivity.this, new ArrayList<RestaurantDetail>());
    listView.setAdapter(urgentTodosAdapter);
    //Here is where you forgot to add your ParseQuery for 'Restaurants'
    ParseQuery<RestaurantDetail> query = ParseQuery.getQuery(RestaurantDetail.class);
    query.findInBackground(new FindCallback<RestaurantDetail>() {
        public void done(List<RestaurantDetail> resutarantList, ParseException e) {
            if (e == null) {
                if (resutarantList.size() > 0) {
                    for (int i = 0; i < resutarantList.size(); i++) {
                        //you forgot to do this - didn't add anything for the adapter to show.
                        urgentTodosAdapter.add(resutarantList.get(i));
                    }
                } else {
                    // do something if empty
                }
            } else {
                // do something if null
            }
        }
    });
    //This is fine here, but you can also do the same in your adapter class; I'll keep this here and show you where to put it
    //in the adapter as well.
    listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
            // Send single item click data to SingleItemView Class
            Intent random1 = new Intent(MainActivity.this, SingleItemView.class);
            if (Name.size() > i)
                // Pass data "name" followed by the position
                random1.putExtra("Name", Name.get(i).getString("Name"));
            // Open SingleItemView.java Activity
            startActivity(random1);
        }
    });
}
}

CustomAdapter类：

public class CustomAdapter extends ArrayAdapter<RestaurantDetail> {
private final Context mContext;
private List<RestaurantDetail> restrauants;
public CustomAdapter(Context context, List<RestaurantDetail> objects) {
    super(context, R.layout.include_restaurants, objects);
    this.mContext = context;
    this.restrauants = objects;
}

public View getView(final int position, View convertView, final ViewGroup parent) {
    if (convertView == null) {
        LayoutInflater mLayoutInflater = LayoutInflater.from(mContext);
        v = mLayoutInflater.inflate(R.layout.include_restaurants, null);
    }
    ParseImageView todoImage = (ParseImageView) v.findViewById(R.id.icon);
    ParseFile imageFile = object.getParseFile("Logo");
    if (imageFile != null) {
        todoImage.setParseFile(imageFile);
        todoImage.loadInBackground();
    }
    TextView titleTextView = (TextView) v.findViewById(R.id.textView3);
    titleTextView.setText(object.getString("Name"));
    //this is also where you can handle to onClick stuff
    cardView.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

        }
    });

    return v;
}
}

初始化您的解析类：这也是您可以放置getters/setters的地方。

@ParseClassName("YourClassNameInYourDBHere") 
public class ResuaurantDetail(your class here) extends ParseObject
{
 }