package com.banking.xc.utils;
import java.util.ArrayList;
import org.json.JSONException;
import org.json.JSONObject;
import android.os.Handler;
import android.view.Gravity;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.widget.AbsListView;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemSelectedListener;
import android.widget.Gallery;
import android.widget.GridView;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.AbsListView.OnScrollListener;
import skytv_com.banking.enjoymovie.R;
import com.banking.xc.utils.HttpGroup.HttpError;
import com.banking.xc.utils.HttpGroup.HttpResponse;
import com.banking.xc.utils.HttpGroup.HttpSetting;
import com.banking.xc.utils.MyActivity.DestroyListener;
/**
* 不能一个NextPageLoader实例用于多个ListView
*/
public abstract class NextPageLoader implements HttpGroup.OnAllListener, DestroyListener {
private final String TAG = "NextPageLoader";
private MyActivity myActivity;
private Handler handler;
private AdapterView adapterView;
private MySimpleAdapter adapter;
private View loadingView;
protected ArrayList<Object> showItemList = new ArrayList<Object>();// 直接引用当前显示的数据
private boolean loading = false;// 标志位，保证滚动到屏幕底部的时候，不会多次触发加载
private ArrayList<?> nextItemList = null;// 用于预存下一页的数据
private boolean loadedShow = false;// 标志位，如果第二页还在下载的过程中就滚动到页尾部，可以通过该标志位申请下载后马上显示。
private boolean loadedLastPage = false;
private boolean firstLoad = true;// 这个实例对象是否从来没从网络加载过数据，这是头次加载
private boolean isEffect = true;// 是否需要遮罩
private boolean isHolding = false;// 是否静止状态
private boolean isFling = false;// 是否滑行状态
private boolean hasNotify;// 是否存在数据改变通知
private boolean isPreloading;// 是否预加载
private boolean isPaging = true;// 是否分页加载
private int position;
private OnScrollLastListener onScrollLastListener;
protected HttpGroup httpGroup;
protected JSONObject params;
protected String pageNumParamKey = "page";
protected String pageSizeParamKey = "pagesize";
protected Integer pageNum = 1;
protected Integer pageSize = 10;
protected String noDataHint;
protected String functionId;
protected boolean httpNotifyUser = true;// 网络出错是否通知用户
private boolean isFinishing;
/**
* @author lijingzuo
*
* Time: 2010-12-26 上午10:31:40
*
* Name:
*
* Description:
*
* @param myActivity
* 因为这里建立的连接组或连接都要关联到某个myActivity去管理，所以要把myActivity传进来。
* @param listView
* @param loadingView
* 显示加载中的图标
* @param functionId
* 跟服务器连接的functionId
*
*/
public NextPageLoader(MyActivity myActivity, AdapterView adapterView, View loadingView, String functionId) {
this.myActivity = myActivity;
this.handler = myActivity.getHandler();
myActivity.addDestroyListener(this);
httpGroup = this.myActivity.getHttpGroupaAsynPool();
this.adapterView = adapterView;
this.loadingView = loadingView;
this.functionId = functionId;
this.isPreloading = true;
}
public NextPageLoader(MyActivity myActivity, AdapterView adapterView, View loadingView, String functionId, JSONObject params) {
this(myActivity, adapterView, loadingView, functionId);
this.params = params;
this.isPreloading = true;
}
public NextPageLoader(MyActivity myActivity, AdapterView adapterView, View loadingView, String functionId, JSONObject params, String noData) {
this(myActivity, adapterView, loadingView, functionId, params);
this.noDataHint = noData;
this.isPreloading = true;
}
public void setHttpNotifyUser(boolean httpNotifyUser) {
this.httpNotifyUser = httpNotifyUser;
}
public void showPageOne() {
// if (showItemList.size() < 1) {
applyLoadedShow();
tryShowNextPage();
// }
}
/**
*
* Time: 2010-12-26 下午02:26:37
*
* Name:
*
* Description: 是否加载过最后一页
*
* @return
*
*/
private boolean isLoadedLastPage() {
// TODO Auto-generated method stub
return loadedLastPage;
}
public abstract void setSelection(int postion);
/**
* @author lijingzuo
*
* Time: 2010-12-25 下午04:27:26
*
* Name:
*
* Description: 当需要下载下一页数据时，加锁。目前没有正在下载的，那么返回true，可以加锁，否则返回false。
*
* @return
*
*/
private synchronized boolean loadingLock() {
if (!loading) {// 如果没有加载中就改为加载中
loading = true;
return loading;
}
return false;
}
/**
* @author lijingzuo
*
* Time: 2010-12-25 下午04:27:29
*
* Name:
*
* Description: 下载完毕时，解锁
*
*
*/
private synchronized void loadingUnLock() {
loading = false;
}
/**
* @author lijingzuo
*
* Time: 2010-12-25 下午04:06:08
*
* Name:
*
* Description: 下载后判断是否需要马上显示
*
* @return
*
*/
private boolean loadedShow() {
if (loadedShow) {
loadedShow = false;
return true;
} else {
return false;
}
}
class GalleryListener implements OnItemSelectedListener{
@Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
int count = showItemList.size()-1;
if(count == position){
if (isFinishing) {
return;
}
if (!isLoadedLastPage()) {
tryShowNextPage();
}
}
}
@Override
public void onNothingSelected(AdapterView<?> parent) {
}
}
/**
* @author lijingzuo
*
* Time: 2010-12-25 下午04:33:55
*
* Name:
*
* Description: 申请要求下载后马上显示
*
* @return
*
*/
private void applyLoadedShow() {
loadedShow = true;
}
/**
* @author lijingzuo
*
* Time: 2010-12-25 下午03:59:12
*
* Name:
*
* Description: 根据网络返回的httpResponse内容转换为列表需要的beanList。如果转换过程发生异常，无法满足基本显示要求 ，请返回空，此类会自动调用错误呈现。
*
* @param httpResponse
* @return
*
*/
protected abstract ArrayList<?> toList(HttpResponse httpResponse);
/**
* @author lijingzuo
*
* Time: 2010-12-25 下午04:00:55
*
* Name:
*
* Description: 错误呈现逻辑
*
*
*/
protected abstract void showError();
/**
* @author lijingzuo
*
* Time: 2010-12-25 下午04:06:12
*
* Name:
*
* Description: 创建自定义 adapter
*
* @param context
* @param itemList
* @return
*
*/
protected abstract MySimpleAdapter createAdapter(MyActivity myActivity, AdapterView adapterView, ArrayList<?> itemList);
/**
* @author lijingzuo
*
* Time: 2010-12-25 上午10:03:06
*
* Name:
*
* Description: 显示下一页的逻辑。注意：应该在此方法前准备好数据；此方法应该执行在UI线程之外；此方法属于控制层
*
* @param itemList
*
*/
private void showNextPage(ArrayList<?> itemList) {
// 下页已经投入使用
nextItemList = null;
showItemList.addAll(itemList);
if (Log.D) {
System.out.println("showItemList size = " + showItemList.size());
}
if (showItemList.size() < 1 && adapterView instanceof ListView && adapterView.getAdapter() == null) {
TextView textView = new TextView(myActivity);
textView.setGravity(Gravity.CENTER);
if (null != this.noDataHint) {
textView.setText(noDataHint);
} else {
textView.setText(R.string.no_data);
}
textView.setTextSize(17);
textView.setPadding(0, 20, 0, 20);
// ((ListView) listView).addHeaderView(textView);
((ListView) adapterView).addHeaderView(textView, R.string.no_data, false);
}
if (itemList.size() < pageSize || !isPaging) {
// 最后一页
loadedLastPage = true;
if (adapterView instanceof ListView)
((ListView) adapterView).setOnScrollListener(null);
} else {
if (Log.D) {
System.err.println("showNextPage() isPreloading " + isPreloading);
}
pageNum++;
loading();// 如果要显示这页就马上继续加载下一页
}
if (null == adapter) {
// 通过实现方法返回自定义的 adapter
adapter = createAdapter(myActivity, adapterView, showItemList);
adapter.setNextPageLoader(this);
// XXX 下拉到低的时候触发，一般默认，预留扩展
final OnScrollLastListener onScrollLastListener = new OnScrollLastListener() {
@Override
public void onScrollLast() {
if (isFinishing) {
return;
}
if (!isLoadedLastPage()) {
tryShowNextPage();
}
}
@Override
public void onScrollFling() {// 滚动滑动时
isFling = true;
}
@Override
public void onScrollIdle() {// 滚动停止时
isHolding = false;
isFling = false;
if (isFinishing) {
return;
}
if (hasNotify) {// 是否需要更新
hasNotify = false;
if (adapter != null) {
adapter.notifyDataSetChanged();
}
}
checkLast();
}
};
adapterView.setOnTouchListener(new ListView.OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
isHolding = true;
break;
case MotionEvent.ACTION_UP:
if (!isFling) {
onScrollLastListener.onScrollIdle();
}
break;
}
return false;
}
});
if (Log.D) {
System.out.println("setAdapter adpter size = " + adapter.getCount());
}
adapterView.setAdapter(adapter);
if (adapterView instanceof ListView){
((ListView) adapterView).setOnScrollListener(onScrollLastListener);
}else if(adapterView instanceof GridView){
((GridView) adapterView).setOnScrollListener(onScrollLastListener);
}else if(adapterView instanceof Gallery){
((Gallery) adapterView).setOnItemSelectedListener(new GalleryListener());
adapterView.setOnTouchListener(new OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
return false;
}
});
}
loadingUnLock();
} else {
adapter.notifyDataSetChanged();
loadingUnLock();
}
// 通过简单的延迟方式以达到要求，应该准确地在能正确获取getChildCount时，马上执行。
handler.postDelayed(new Runnable() {
public void run() {
if (adapterView != null) {
if (showItemList.size() <= adapterView.getChildCount()) {// 如果读取内容还不足一屏显示则马上尝试显示下一屏幕
tryShowNextPage();
}
}
}
}, 500);
if (isLoadedLastPage()) {// 如果加载过最后一页了，那么取出加载效果进度条
if (adapterView instanceof ListView) {
((ListView) adapterView).removeFooterView(loadingView);
}
}
}
/**
* @author lijingzuo
*
* Time: 2011-1-24 下午08:31:37
*
* Name:
*
* Description: 在加载前处理参数
*
*
*/
protected void handleParamsBeforeLoading() {
try {
// XXX pageNumParamKey 已预留接口可以修改
getParams().put(pageNumParamKey, "" + pageNum);
// XXX pageSizeParamKey 和 pageSize 已预留接口可以修改
getParams().put(pageSizeParamKey, "" + pageSize);
} catch (JSONException e) {
if (Log.V) {
Log.v("NextPageLoader", "JSONException -->> ", e);
}
}
}
/**
* @author lijingzuo
*
* Time: 2010-12-26 上午08:41:41
*
* Name:
*
* Description: 非UI线程到网络取得数据后执行
*
*
*/
protected void loading() {
handleParamsBeforeLoading();
// XXX 连接方式以后可能会需要修改。届时可将此类改名，抽取出父类，此处由子类实现。
HttpSetting httpSetting = new HttpGroup.HttpSetting();
//httpSetting.setJsonParams(getParams());
httpSetting.setListener(this);
httpSetting.setNotifyUser(httpNotifyUser);
if (firstLoad && isEffect) {// 第一页需要遮罩层
httpSetting.setEffect(HttpSetting.EFFECT_DEFAULT);
} else {// 第一页之后
httpSetting.setEffect(HttpSetting.EFFECT_NO);
}
firstLoad = false;
httpGroup.add(httpSetting);
// httpGroup.add(functionId, params, listener);
}
public void setEffect(boolean isEffect) {
this.isEffect = isEffect;
}
/**
* @author lijingzuo
*
* Time: 2010-12-25 下午04:39:38
*
* Name:
*
* Description: 尝试显示下一页。每次滚动到最后一行会触发这个
*
*
*/
private void tryShowNextPage() {
if (loadedLastPage) {// 如果已经是最后一页，不作尝试
if (Log.D) {
Log.v(TAG,"loadedLast Page " + loadedLastPage);
}
return;
}
if (null == nextItemList) {// 预加载数据为空才尝试加载
if (Log.D) {
Log.v(TAG,"nextItemList == null isPreloading " + isPreloading);
}
applyLoadedShow();// 申请要求下载后马上显示
if (!loadingLock()) {// 如果不能加锁代表已经有在下载中
return;
}
if(Log.V){
Log.v(TAG,"isPreloading = "+isPreloading);
}
if (isPreloading)
loading();
} else {// 预加载数据不为空，就直接显示
if (Log.D) {
Log.d("Temp", "show do -->> ");
System.err.println("showNextPage(nextItemList)");
}
showNextPage(nextItemList);
}
}
/**
* @author lijingzuo
*
* Time: 2011-1-23 上午11:59:10
*
* Name:
*
* Description: 被通知数据发生改变
*
*
*/
public void notifyDataSetChanged() {
if (!isHolding) {
if (null != adapter) {
adapter.notifyDataSetChanged();
}
} else {
hasNotify = true;
}
}
/**
* 是否分页
*
* @return
*/
public boolean isPaging() {
return isPaging;
}
/**
* 设置是否启用分页
*
* @param isPaging
*/
public void setPaging(boolean isPaging) {
this.isPaging = isPaging;
}
/**
* Copyright 2010 Jingdong Android Mobile Application
*
* @author lijingzuo
*
* Time: 2010-12-25 下午04:07:04
*
* Name:
*
* Description: 滚动到最后一行的监听器逻辑
*/
private abstract class OnScrollLastListener implements OnScrollListener {
private int firstVisibleItem;
private int visibleItemCount;
private int totalItemCount;
@Override
public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
this.firstVisibleItem = firstVisibleItem;
this.visibleItemCount = visibleItemCount;
this.totalItemCount = totalItemCount;
setSelection(firstVisibleItem);
}
@Override
public void onScrollStateChanged(AbsListView view, int scrollState) {
switch (scrollState) {
case OnScrollListener.SCROLL_STATE_TOUCH_SCROLL:// 滚动开始时
break;
case OnScrollListener.SCROLL_STATE_FLING:// 滚动滑行时
onScrollFling();
break;
case OnScrollListener.SCROLL_STATE_IDLE:// 滚动停止时
onScrollIdle();
break;
}
}
public void checkLast() {
if (firstVisibleItem + visibleItemCount == totalItemCount) {
onScrollLast();
}
}
public abstract void onScrollFling();// 滚动滑行时
public abstract void onScrollIdle();// 滚动停止时
public abstract void onScrollLast();// 滚动到最后一项时
}
/**
* @author lijingzuo
*
* Time: 2010-12-26 上午09:59:14
*
* Name:
*
* Description: 可以通过此方法自定义跟服务器通讯的pageNum参数名
*
* @param pageNumParamKey
*
*/
public void setPageNumParamKey(String pageNumParamKey) {
this.pageNumParamKey = pageNumParamKey;
}
/**
* @author lijingzuo
*
* Time: 2010-12-26 上午09:59:16
*
* Name:
*
* Description: 可以通过此方法自定义跟服务器通讯的pageSize参数名
*
* @param pageSizeParamKey
*
*/
public void setPageSizeParamKey(String pageSizeParamKey) {
this.pageSizeParamKey = pageSizeParamKey;
}
/**
* @author lijingzuo
*
* Time: 2010-12-26 上午09:59:20
*
* Name:
*
* Description: 可以通过此方法自定义每页显示的行数
*
* @param pageSize
*
*/
public void setPageSize(int pageSize) {
this.pageSize = pageSize;
}
/**
* @author lijingzuo
*
* Time: 2010-12-26 上午11:39:58
*
* Name:
*
* Description: 获得的是引用，理论上可以在任何时候直接控制发出请求时的参数。 注意：页码和每页行数在发送前会被覆盖，请不要依靠此处控制，通过其他方法可以自定义，由内部控制； 最好在显示头一页之前就确定，开始使用后最好不要再去修改； 尽量不要被多线程控制和持有此对象，不实现多线程安全。
*
* @return
*
*/
public JSONObject getParams() {
return null == params ? params = new JSONObject() : params;
}
/**
* 修改数据（外部调用）
*/
public void modifyData(ModifyDataRunnable runnable) {
if (!isHolding) {
runnable.modifyData(this.showItemList);
adapter.notifyDataSetChanged();
} else {
// TODO 2011-05-10 任务队列
}
}
/**
* 修改方法
*/
public interface ModifyDataRunnable {
void modifyData(ArrayList<Object> showItemList);
}
/*
* 到网络取得数据后的逻辑
*/
@Override
public void onStart() {
}
@Override
public void onEnd(HttpResponse httpResponse) {
final ArrayList<?> itemList = toList(httpResponse);
handler.post(new Runnable() {
public void run() {
if (isFinishing) {
return;
}
if (null == itemList) {// 返回空就呈现错误提示
showError();
return;
}
nextItemList = itemList;
if (loadedShow()) {// 是否马上显示
if (Log.D) {
Log.d("Temp", "show now -->> ");
System.err.println("showNextPage(itemList)");
}
showNextPage(itemList);// 这个方法里面会自动又继续加载下一页
}
}
});
}
public void setAdapterView(AdapterView adapterView) {
if (this.adapterView == adapterView) {
return;
}
this.adapterView.setVisibility(View.GONE);
this.adapterView = null;
this.adapter = null;
this.adapterView = adapterView;
if (this.adapterView != null) {
this.adapterView.setVisibility(View.VISIBLE);
isPreloading = false;
showPageOne();
}
if (Log.D) {
System.out.println("adapterView is null " + this.adapterView);
}
}
@Override
public void onProgress(int max, int progress) {
}
@Override
public void onError(HttpError error) {
loadingUnLock();
showError();
}
public ArrayList<?> getAllProductList() {
return showItemList;
}
public Integer getPageNum() {
return pageNum;
}
public Integer getPageSize() {
return pageSize;
}
@Override
public void onDestroy() {
isFinishing = true;
myActivity = null;
adapterView = null;
adapter = null;
loadingView = null;
showItemList = null;
nextItemList = null;
httpGroup = null;
params = null;
}
}