Question

我正在解析json数据并使用BaseAdapter在自定义ListView中显示。我在解析数据时没有问题。也没有任何问题将数据设置为ModelClass.java（setters和getters类），只有问题是如何从ModelClass.java获取数据。请帮忙。

这是我的MainActivity.java

public class MainActivity extends ActionBarActivity {

    // url to make request(to get the latest 20 feeds).
    private static String url = "http;.....";
    // JSON Node names
    private static final String TAG_BODY = "body";
    private static final String TAG_CREATED_AT = "created_at";
    private static final String TAG_DATE_TIME = "date_time";
    private static final String TAG_DEPARTEMENT = "department";
    private static final String TAG_ID = "id";
    private static final String TAG_INCLUDE = "include";
    private static final String TAG_MEDI_TYPE = "mediaType";
    private static final String TAG_PRIORITY = "priority";
    private static final String TAG_TITLE = "title";
    private static final String TAG_UPDATED_AT = "updated_at";
    private static final String TAG_USER_ID = "user_id";
    ProgressDialog progressDialog;
    ListView listViewFeeds;
    // String mTitle, mBody;
    List<ModelClass> model = new ArrayList<ModelClass>();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        /* To display the feed */
        listViewFeeds = (ListView) findViewById(R.id.listViewFeeds);
        listViewFeeds.setAdapter(new NewAdapter(this));

        Feeds feeds = new Feeds();
        feeds.execute();
    }

    public class Feeds extends AsyncTask<Void, Void, Void> {

        @Override
        protected void onPreExecute() {
            progressDialog = new ProgressDialog(MainActivity.this);
            progressDialog.setTitle("Loading ...");
            progressDialog.show();
            super.onPreExecute();
        }

        @Override
        protected Void doInBackground(Void... arg0) {
            HttpClient httpClient = new DefaultHttpClient();
            HttpGet httpGet = new HttpGet(url);
            httpGet.setHeader("Accept", "application/json");
            try {
                HttpResponse httpResponse = httpClient.execute(httpGet);
                StatusLine statusLine = httpResponse.getStatusLine();
                int statusCode = statusLine.getStatusCode();
                if (statusCode != 200) {
                    return null;
                }
                HttpEntity httpEntity = httpResponse.getEntity();
                InputStream inputStream = httpEntity.getContent();
                BufferedReader bufferedReader = new BufferedReader(
                        new InputStreamReader(inputStream));
                StringBuilder stringBuilder = new StringBuilder();
                String line;
                while ((line = bufferedReader.readLine()) != null) {
                    stringBuilder.append(line);
                }
                String jsonData = stringBuilder.toString();

                // Displaying json data in logcat.
                Log.d("Latest 20 feeds", jsonData);

                JSONArray array = new JSONArray(jsonData);
                for (int i = 0; i < array.length(); i++) {
                    JSONObject object = array.getJSONObject(i);
                    String mTitle = object.getString("title");
                    String mBody = object.getString("body");
                    System.out.println("Titlte: " + mTitle);
                    System.out.println("Body: " + mBody);
                    // Setting the data to ModelClass
                    ModelClass mc = new ModelClass(mTitle, mBody);
                }

            } catch (ClientProtocolException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            } catch (JSONException e) {
                e.printStackTrace();
            }
            return null;
        }

        @Override
        protected void onPostExecute(Void result) {
            progressDialog.dismiss();
            super.onPostExecute(result);
        }

    }

}

class NewAdapter extends BaseAdapter {
    ArrayList<ModelClass> list;
    Context context;

    NewAdapter(Context c) {
        context = c;
    }

    @Override
    public int getCount() {
        return 0;
        // return list.size();
    }

    @Override
    public Object getItem(int position) {
        return list.get(position);
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {

        LayoutInflater inflater = (LayoutInflater) context
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        View row = inflater.inflate(R.layout.single_row_feed_view, parent,
                false);
        TextView title = (TextView) row.findViewById(R.id.textViewTitleFeeds);
        TextView body = (TextView) row.findViewById(R.id.textViewBody);

        ModelClass temp = list.get(position);
        title.setText(temp.title);
        body.setText(temp.body);
        return row;
    }

}

这是我的ModelClass.java

public class ModelClass {
    String title;
    String body;

     ModelClass(String title, String body) {
     this.title = title;
     this.body = body;
     }
}

activity_main.xml文件

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

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

</LinearLayout>

single_row_feed_view.xml文件（行显示在ListView中）

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <TextView
        android:id="@+id/textViewTitleFeeds"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_toRightOf="@+id/viewColor"
        android:ellipsize="end"
        android:maxLines="2"
        android:text="TextView"
        android:textSize="12dp" />

    <TextView
        android:id="@+id/textViewBody"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_below="@+id/textViewTitleFeeds"
        android:layout_marginTop="3dp"
        android:ellipsize="end"
        android:maxLines="2"
        android:text="TextView"
        android:textSize="8dp" />

</RelativeLayout>

Answer 1

这是你要求的吗？

   //Inside your Model class:

 public String getTitle(){
    return this.title;
    }

    public String setTitle(String givenTitle){
    this.title = givenTitle;
    }

    public String getBody(){
    return this.body;
    }

    public String setTitle(String givenBody){
    this.body = givenBody;
    }

Answer 2

有点难以解决确切的问题，因为你问的是如何从setter和getters类中获取值，但你的ModelClass没有getter或setter。

你可以将getter放入你的ModelClass中，但如果它在同一个包中，你可能在技术上不需要它们。

你应该看看这个教程。这对我帮助很大。 http://www.vogella.com/tutorials/AndroidListView/article.html

Answer 3

正如其他人提到的那样，你需要在模型类中加入getter和setter。在将值放入列表并格式化列表项方面，您需要一个自定义列表适配器。然后创建要放入列表适配器的项目列表..然后显示列表。以下是一个例子。

enter code here
 public class ExampleListAdapter extends ArrayAdapter<ExampleModel> {

 private Context                     context;
 private ArrayList<ExampleModel> items;

 public ExampleListAdapter(Context context, ArrayList<ExampleModel> items) {
    super(context, R.id.result_list_item_direction_icon, items);

    this.context = context;
    this.items = items;
}

 @Override
 public View getView(int position, View convertView, ViewGroup parent) {
    LayoutInflater inflater = null;
    View rowView = convertView;

    //Get rowView from inflater
    inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    rowView = inflater.inflate(R.id.yourcustom_layout, parent, false);

    // Get reference ids from the rowView
   //example
    TextView item = (TextView) rowView.findViewById(R.id.itemID);


    // Set the values for items in custom list view

    item.setText(items.get(position).yourGetter());


    return rowView;
 }

}

然后在课程中你要使用它......

enter code here
  ArrayList<t> yourList = new ArrayList<t>();
  yourList = getValuesFromDBOROtherSource;//make sure the return value is list!
  yourCustomAdapter = new ExampleListAdapter(getActivity(), yourList);

  setListAdapter(yourCustomAdapter);

无法理解如何从setter和getters类中获取值

3 个答案: