Question

我已经完成了json解析器获取网站内容，我的第一页显示了listview中的几个作业列表，其中应该只包含id，date和author name，点击singleitem列表后，我应该获取图像和数据内容，我能够获得内容，但我不知道如何在单项列表中获取图像。有谁知道怎么做？

public class AndroidJSONParsingActivity extends ListActivity {

// url to make request
private static String url = "http://www.mysite.com/jobs/?json=get_recent_posts";

// 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);

        }
    });

单一菜单列表的代码

公共类SingleMenuItemActivity扩展了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

图像会有一个Web链接，您可以从以下代码下载Web图像。

public static Drawable LoadImageFromWebOperations(String url) {
  try {
    InputStream is = (InputStream) new URL(url).getContent();
    Drawable d = Drawable.createFromStream(is, "src name");
    return d;
} catch (Exception e) {
    return null;
 }
}

Answer 2

下载图像后，使用createScaledBitmap（Bitmap src，int dstWidth，int dstHeight，boolean filter）或者，对于Android2.2及更高版本，使用Bitmap extractThumbnail（Bitmap source，int width，int height）创建缩略图图像。

如何在使用json解析器中获取图像

2 个答案: