在自动加载时，我需要能够从URL加载更多项目。我通过Json获取数据的地方。
在我的API调用类中，我需要添加到此nuber 10中：
pairs.add(new BasicNameValuePair("limit", "10"));
每当列表视图完成加载当前数据时，然后更改上面的值并再次检查。
我虽然需要在PaginationDemoActivity中创建一个方法，它检查是否有更多页面，然后使用intent传递一个新变量来覆盖（＆＃34; limit＆＃34;，＆＃34; 10＆＃34;） ）在JSONfunctions类
中有什么建议吗？谢谢你们
JSONfunctions
public class JSONfunctions extends Activity{
public static JSONObject getJSONfromURL(String url) {
InputStream is = null;
String result = "";
JSONObject jArray = null;
// Download JSON data from URL
try {
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(url);
//Add URL Encoding by sending post data
List<NameValuePair> pairs = new ArrayList<NameValuePair>();
pairs.add(new BasicNameValuePair("c","getlist"));
pairs.add(new BasicNameValuePair("page","1"));
pairs.add(new BasicNameValuePair("limit", "10"));
UrlEncodedFormEntity entity = new UrlEncodedFormEntity(pairs,HTTP.UTF_8);
httppost.setEntity(entity);
// end Add URL Encoding by sending post data
HttpResponse httpResponse = httpclient.execute(httppost);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
//end test
/*
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
is = entity.getContent();
*/
} catch (Exception e) {
Log.e("log_tag", "Error in http connection " + e.toString());
}
// Convert response to string
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();
result = sb.toString();
} catch (Exception e) {
Log.e("log_tag", "Error converting result " + e.toString());
}
try {
jArray = new JSONObject(result);
} catch (JSONException e) {
Log.e("log_tag", "Error parsing data " + e.toString());
}
return jArray;
}
}
数据
public class Data {
static String URL = " my api url";
static String itemsPerPage = "20";
public static final String TAG = Data.class.getSimpleName();
public static List<Pair<String, List<Composer>>> getAllData() {
List<Pair<String, List<Composer>>> res = new ArrayList<Pair<String, List<Composer>>>();
for (int i = 0; i < 4; i++) {
res.add(getOneSection(i));
}
return res;
}
public static List<Composer> getFlattenedData() {
List<HashMap<String, String>> arraylist;
JSONObject jsonobject;
JSONArray jsonarray;
List<Composer> res = new ArrayList<Composer>();
//Pair<String, List<Composer>> mydata;
arraylist = new ArrayList<HashMap<String, String>>();
// Retrieve JSON Objects from the given URL address
jsonobject = JSONfunctions.getJSONfromURL(URL);
Log.e("check", jsonobject.toString());
try {
// Locate the array name in JSON
jsonarray = jsonobject.getJSONArray("data");
for (int i = 0; i < jsonarray.length(); i++) {
HashMap<String, String> map = new HashMap<String, String>();
jsonobject = jsonarray.getJSONObject(i);
// Retrive JSON Objects
map.put("id", jsonobject.getString("id"));
map.put("title", jsonobject.getString("title"));
map.put("s_desc", jsonobject.getString("s_desc"));
map.put("img", jsonobject.getString("img"));
// Set the JSON Objects into the array
arraylist.add(map);
Composer s = new Composer(
jsonobject.getString("title"),
jsonobject.getString("s_desc"),
jsonobject.getString("id"),
jsonobject.getString("img"));
res.add(s);
}
} catch (JSONException e) {
Log.e("Error", e.getMessage());
e.printStackTrace();
}
return res;
}
protected void updateUrlItems()
{
}
public static Pair<Boolean, List<Composer>> getRows(int page) {
List<Composer> flattenedData = getFlattenedData();
if (page == 1) {
return new Pair<Boolean, List<Composer>>(true, flattenedData.subList(0, 5));
} else {
SystemClock.sleep(2000); // simulate loading
return new Pair<Boolean, List<Composer>>(page * 5 < flattenedData.size(),
flattenedData.subList((page - 1) * 5, Math.min(page * 5, flattenedData.size())));
}
}
public static Pair<String, List<Composer>> getOneSection(int index) {
String[] titles = {"", "", "", ""};
Composer[][] composerss = {
{
new Composer("", "", "", ""),
},
};
return new Pair<String, List<Composer>>(titles[index], Arrays.asList(composerss[index]));
}
}
PaginationDemoActivity
public class PaginationDemoActivity extends Activity {
AmazingListView lsComposer;
PaginationComposerAdapter adapter;
ImageLoader imageLoader;
// Flag for current page
static Integer current_page = 10;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_pagination_demo);
imageLoader = new ImageLoader(this);
lsComposer = (AmazingListView) findViewById(R.id.lsComposer);
lsComposer.setLoadingView(getLayoutInflater().inflate(R.layout.loading_view, null));
lsComposer.setAdapter(adapter = new PaginationComposerAdapter());
adapter.notifyMayHaveMorePages();
}
public void bRefresh_click(View v) {
adapter.reset();
adapter.resetPage();
adapter.notifyMayHaveMorePages();
}
class PaginationComposerAdapter extends AmazingAdapter {
List<Composer> list = Data.getRows(1).second;
private AsyncTask<Integer, Void, Pair<Boolean, List<Composer>>> backgroundTask;
public void reset() {
if (backgroundTask != null) backgroundTask.cancel(false);
list = Data.getRows(1).second;
notifyDataSetChanged();
}
@Override
public int getCount() {
return list.size();
}
@Override
public Composer getItem(int position) {
return list.get(position);
}
@Override
public long getItemId(int position) {
return position;
}
@Override
protected void onNextPageRequested(int page) {
Log.d(TAG, "Got onNextPageRequested page=" + page);
if (backgroundTask != null) {
backgroundTask.cancel(false);
}
backgroundTask = new AsyncTask<Integer, Void, Pair<Boolean, List<Composer>>>() {
@Override
protected Pair<Boolean, List<Composer>> doInBackground(Integer... params) {
int page = params[0];
Log.e("more page", "page: " + page);
return Data.getRows(page);
}
@Override
protected void onPostExecute(Pair<Boolean, List<Composer>> result) {
if (isCancelled()) return;
Log.e("onPostExecute", "result: " + result.first);
list.addAll(result.second);
nextPage();
notifyDataSetChanged();
if (result.first) {
// still have more pages
notifyMayHaveMorePages();
} else {
notifyNoMorePages();
}
};
}.execute(page);
}
@Override
protected void bindSectionHeader(View view, int position, boolean displaySectionHeader) {
}
@Override
public View getAmazingView(int position, View convertView, ViewGroup parent) {
View res = convertView;
if (res == null) res = getLayoutInflater().inflate(R.layout.item_composer, null);
// we don't have headers, so hide it
res.findViewById(R.id.header).setVisibility(View.GONE);
TextView lName = (TextView) res.findViewById(R.id.lName);
TextView lYear = (TextView) res.findViewById(R.id.lYear);
TextView lId = (TextView) res.findViewById(R.id.lId);
// Locate the ImageView in listview_item.xml
ImageView lImg = (ImageView) res.findViewById(R.id.lImg);
Composer composer = getItem(position);
lName.setText(composer.name);
lYear.setText(composer.year);
lId.setText(composer.id);
Log.e("getAmazingView PRINT THE URL 1111111111", "URL: " + composer.img);
// Capture position and set results to the ImageView
// Passes img images URL into ImageLoader.class
imageLoader.DisplayImage(composer.img, lImg);
Log.e("222","333");
//khen
lsComposer.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View v, int position, long id) {
// TODO Auto-generated method stub
if(id > -1){
Composer composer = adapter.getItem(position);
Intent intent = new Intent();
intent.setClass(getApplicationContext(), SingleItemView.class);
Bundle bundle = new Bundle();
bundle.putString("id", composer.id);
bundle.putString("name", composer.name);
bundle.putString("year", composer.year);
bundle.putString("img", composer.img);
intent.putExtras(bundle);
startActivity(intent);
}
}
});
//end khen
return res;
}
@Override
public void configurePinnedHeader(View header, int position, int alpha) {
}
@Override
public int getPositionForSection(int section) {
return 0;
}
@Override
public int getSectionForPosition(int position) {
return 0;
}
@Override
public Object[] getSections() {
return null;
}
}
}