Question

我正在使用JSON解析器来解析JSON Response，我可以在ListView中获取项目名称，但我无法获得与之对应的图像。其中图像url存在于JSON响应中。如何解析响应以获取与项目对应的图像。以下是代码，任何知道如何做到这一点的人都会帮助我，这将非常有用。

注意：图像和项目不固定

public class AndroidJSONParsingActivity extends ListActivity {

// url to make request
private static String url = "website/?JSON=get_recent_post";

// JSON Node names
private static final String TAG_POSTS = "posts";
private static final String TAG_ID = "id";
private static final String TAG_TITLE = "title";
private static final String TAG_DATE = "date";
private static final String TAG_CONTENT = "content";
private static final String TAG_AUTHOR = "author";
private static final String TAG_NAME = "name";



// contacts JSONArray
JSONArray posts = null;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    // Hashmap for ListView
    ArrayList<HashMap<String, String>> contactList = new ArrayList<HashMap<String, String>>();

    // Creating JSON Parser instance
    JSONParser jParser = new JSONParser();

    // getting JSON string from URL
    JSONObject json = jParser.getJSONFromUrl(url);

    try {
        // Getting Array of Contacts
        posts = json.getJSONArray(TAG_POSTS);

        // looping through All Contacts
        for(int i = 0; i < posts.length(); i++){
            JSONObject c = posts.getJSONObject(i);

            // Storing each json item in variable
            String id = c.getString(TAG_ID);
            String title = c.getString(TAG_TITLE);
            String date = c.getString(TAG_DATE);
            String content = c.getString(TAG_CONTENT);

            // Phone number is agin  JSON Object
            JSONObject author = c.getJSONObject(TAG_AUTHOR);
            String name = author.getString(TAG_NAME);


            // creating new HashMap
            HashMap<String, String> map = new HashMap<String, String>();

            // adding each child node to HashMap key => value
            map.put(TAG_ID, id);
            map.put(TAG_TITLE, title);
            map.put( TAG_DATE, date);
            map.put( TAG_NAME, name);
            map.put( TAG_CONTENT, content);
            // adding HashList to ArrayList
            contactList.add(map);
        }   
    } catch (JSONException e) {
        e.printStackTrace();
    }


    /**
     * Updating parsed JSON data into ListView
     * */
    ListAdapter adapter = new SimpleAdapter(this, contactList,
            R.layout.list_item,
            new String[] { TAG_TITLE, TAG_DATE, TAG_NAME, TAG_CONTENT }, new int[] {
                    R.id.name, R.id.email,R.id.mobile, R.id.content });

    setListAdapter(adapter);

    // selecting single ListView item
    ListView lv = getListView();

    // Launching new screen on Selecting Single ListItem
    lv.setOnItemClickListener(new OnItemClickListener() {

        public void onItemClick(AdapterView<?> parent, View view,
                int position, long id) {
            // getting values from selected ListItem
            String title = ((TextView) view.findViewById(R.id.name)).getText().toString();
            String date = ((TextView) view.findViewById(R.id.email)).getText().toString();
            String name = ((TextView) view.findViewById(R.id.mobile)).getText().toString();
            String content = ((TextView) view.findViewById(R.id.content)).getText().toString();

            // Starting new intent
            Intent in = new Intent(getApplicationContext(), SingleMenuItemActivity.class);
            in.putExtra(TAG_TITLE, title);
            in.putExtra(TAG_DATE, date);
            in.putExtra(TAG_NAME, name);
            in.putExtra(TAG_CONTENT, content);
            startActivity(in);

        }
    });



}

}

JSONParser.java

公共类JSONParser {

static InputStream is = null;
static JSONObject jObj = null;
static String json = "";

// constructor
public JSONParser() {

}

public JSONObject getJSONFromUrl(String url) {

    // Making HTTP request
    try {
        // defaultHttpClient
        DefaultHttpClient httpClient = new DefaultHttpClient();
        HttpPost httpPost = new HttpPost(url);

        HttpResponse httpResponse = httpClient.execute(httpPost);
        HttpEntity httpEntity = httpResponse.getEntity();
        is = httpEntity.getContent();           

    } catch (UnsupportedEncodingException e) {
        e.printStackTrace();
    } catch (ClientProtocolException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }

    try {
        BufferedReader reader = new BufferedReader(new InputStreamReader(
                is, "iso-8859-1"), 8);
        StringBuilder sb = new StringBuilder();
        String line = null;
        while ((line = reader.readLine()) != null) {
            sb.append(line + "\n");
        }
        is.close();
        json = sb.toString();
    } catch (Exception e) {
        Log.e("Buffer Error", "Error converting result " + e.toString());
    }

    // try parse the string to a JSON object
    try {
        jObj = new JSONObject(json);
    } catch (JSONException e) {
        Log.e("JSON Parser", "Error parsing data " + e.toString());
    }

    // return JSON String
    return jObj;

}

}

SingleMenuItem.java

public class SingleMenuItemActivity  extends Activity {

// JSON node keys
private static final String TAG_TITLE = "title";
private static final String TAG_DATE = "date";
private static final String TAG_NAME = "name";
private static final String TAG_CONTENT = "content";
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.single_list_item);

    // getting intent data
    Intent in = getIntent();

    // Get JSON values from previous intent
    String title = in.getStringExtra(TAG_TITLE);
    String date = in.getStringExtra(TAG_DATE);
    String name = in.getStringExtra(TAG_NAME);
    String content = in.getStringExtra(TAG_CONTENT);

    // Displaying all values on the screen
    TextView lblName = (TextView) findViewById(R.id.name_label);
    TextView lblCost = (TextView) findViewById(R.id.email_label);
    TextView lblDesc = (TextView) findViewById(R.id.mobile_label);
    TextView lblCont = (TextView) findViewById(R.id.content_label);

    lblName.setText(title);
    lblCost.setText(date);
    lblDesc.setText(name);
    lblCont.setText(content);
}

}

Answer 1

你必须使自己的适配器扩展BaseAdapter以获得更多的自由和灵活性......这不是太难，你只需要将列表行的元素与相应行的json数据绑定在一起...在此绑定上，您还将获取图像，并分配给ImageViews。

SimpleAdapter用于非常简单的事情。

将图像添加到与其内容相对应的ListView，从JSON响应中获取

1 个答案: