我在viewpager中使用了一个可扩展的列表视图。每个页面都有expandablelistview。单击时，它将显示子视图。每个子视图都有两个按钮和一个textview。按钮用于设置值到textview，例如。递增/递减。我现在面临的问题是，在刷页面时，值会随着textview的所有子视图设置为0（零）而改变。我尝试了下面的代码，但在此之后没有调用getChildView（）并且它也没有扩展我的组。
OrderActivity.java
public class OrderActivity extends FragmentActivity{
private SlidingTabLayout mSlidingTabLayout;
private ViewPager mViewPager;
//private ExpandableListAdapter mAdapter; // added new
private SamplePagerAdapter myAdapter;
List<Fragment> myFragments;
List<String> catList = AppConstants.CATEGORY_LIST;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.fragment_sliding_content);
getActionBar().setDisplayHomeAsUpEnabled(true);
getActionBar().setDisplayShowHomeEnabled(true);
this.myAdapter = new SamplePagerAdapter();
mViewPager = (ViewPager)findViewById(R.id.viewpager);
mViewPager.setAdapter(this.myAdapter);
mSlidingTabLayout = (SlidingTabLayout)findViewById(R.id.sliding_tabs);
mSlidingTabLayout.setViewPager(mViewPager);
final ImageButton cartImgBtn = (ImageButton)findViewById(R.id.imgBtnCart);
TextView totalCntItem = (TextView)findViewById(R.id.tvCartItemCount);
}
@Override
public void onBackPressed() {
super.onBackPressed();
}
public class SamplePagerAdapter extends FragmentPagerAdapter {
Fragment fragment;
public SamplePagerAdapter() {
super(getSupportFragmentManager());
}
@Override
public int getCount() {
return catList.size();
}
@Override
public Fragment getItem(int position) {
switch(position){
case 0: fragment = new BeveragesFragment();
return fragment;
case 1: fragment = new LightFoodFragment();
return fragment;
case 2: fragment = new SoftDrinksFragment();
return fragment;
case 3: fragment = new FastFoodFragment();
return fragment;
case 4:
case 5:
case 6:
case 7:
case 8:
case 9:
case 10:
case 11:
case 12:
case 13: fragment = new BeveragesFragment();
return fragment;
default:
return null;
}
}
@Override
public int getItemPosition(Object object) {
return POSITION_NONE ;
}
@Override
public CharSequence getPageTitle(int position) {
return catList.get(position);
}
}
}
BeverageFragment.java
public class BeveragesFragment extends Fragment{
//public static int totalCounter=0;
//ItemDetails myCartItem;
//ArrayList<ItemDetails> cartItems = new ArrayList<ItemDetails>();
//ExpandableListAdapter beverageAdapter;
ExpandableListView exListCategory;
public BeveragesFragment(){
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
@Override
public void setUserVisibleHint(boolean isVisibleToUser) {
super.setUserVisibleHint(isVisibleToUser);
if(isVisibleToUser){
if (ConnectionDetector.isInternetAvailable(getActivity())) {
new CategoryJSONAsyncTask().execute("http://112.145.152.25/..../GetCateenOrderCategoryItemListDetail?CategoryID=1");
} else {
Utility.buildDialog(getActivity()).show();
}
}
}
@Override
public View onCreateView(LayoutInflater inflater, final ViewGroup container, final Bundle savedInstanceState) {
// Create the view from XML layout.
final View view = inflater.inflate(R.layout.fragment_beverages, null);
// Perform additional configuration on layout components here.
TextView txt1 = (TextView) view.findViewById(R.id.textView);
txt1.setText("HIIIIIIIIIIIIIIIIIIIII");
exListCategory = (ExpandableListView) view.findViewById(R.id.myExpandableListView);
exListCategory.setDividerHeight(2);
return view;
}
public class CategoryJSONAsyncTask extends AsyncTask<String,Void,String> {
@Override
protected void onPreExecute() {
super.onPreExecute();
}
@Override
protected String doInBackground(String... params) {
String result = "";
try {
HttpGet httpGet = new HttpGet(params[0]);
httpGet.setHeader("Authorization","BASIC"+" "+ AppConstants.KEY);
HttpClient httpclient = new DefaultHttpClient();
HttpResponse response = httpclient.execute(httpGet);
int status = response.getStatusLine().getStatusCode();
if (status == 200) {
HttpEntity entity = response.getEntity();
result = EntityUtils.toString(entity);
return result;
}
return result;
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
@Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
ArrayList<CategoryParentItemList> listParent = fetchResponse(result.replace("\n","").trim());
CategoryItemListAdapter adapter = new CategoryItemListAdapter(BeveragesFragment.this.getActivity(),listParent);
exListCategory.setAdapter(adapter);
adapter.notifyDataSetChanged();
// here following line of code which not worked
/// totalCntItem.setText(String.format("%d",CategoryItemListAdapter.getTotalCounter()));
}
}
public ArrayList<CategoryParentItemList> fetchResponse(String result)
{
ArrayList<CategoryParentItemList> listParent = new ArrayList<>();
if (!result.equals(""))
{
try
{
JSONObject jsono = new JSONObject(result);
JSONArray jarray = jsono.getJSONArray("SBL");
CategoryParentItemList parent;
for (int i = 0; i < jarray.length(); i++)
{
ArrayList<CategoryChildListItem> childrens = new ArrayList<>();
childrens.clear();
CategoryChildListItem child;
JSONObject object = jarray.getJSONObject(i);
System.out.println("SCI: " + object.getInt("SubCategoryID"));
System.out.println("SCN: " + object.getString("SubCategoryName"));
JSONArray subItemArray = object.getJSONArray("SubCategoryItemList");
if (subItemArray.length() > 0)
{
for (int j = 0; j < subItemArray.length(); j++)
{
JSONObject subItemObject = subItemArray.getJSONObject(j);
String strItemName = subItemObject.getString("ItemName");
String strDefaultPrice = subItemObject.getString("DefaultPrice");
child = new CategoryChildListItem(strItemName, strDefaultPrice);
childrens.add(child);
Log.i("strItemName", strItemName);
Log.i("strDefaultPrice", strDefaultPrice);
}
parent = new CategoryParentItemList(object.getString("SubCategoryName"),childrens);
listParent.add(parent);
}
}
}
catch (JSONException e)
{
e.printStackTrace();
}
}
return listParent;
}
}
CategoryItemListAdapter.java
public class CategoryItemListAdapter extends BaseExpandableListAdapter{
private Context context;
public static int totalCounter=0;
ItemDetails myCartItem;
ArrayList<ItemDetails> cartItems = new ArrayList<ItemDetails>();
private ArrayList<CategoryParentItemList> listParent;
static class ViewHolderGroup {
public TextView lblSubCategoryName;
}
static class ViewHolderChild {
public TextView lblItemName;
public TextView lblDefualtPrice;
public TextView lblQty;
public ImageButton imgPlus;
public ImageButton imgMinus;
}
public CategoryItemListAdapter(Context context, ArrayList<CategoryParentItemList> listParent) {
super();
this.context = context;
this.listParent = listParent;
//cartItems = AppConstants.CART_LIST;
}
@Override
public int getGroupCount() {
return listParent.size();
}
@Override
public int getChildrenCount(int groupPosition) {
ArrayList<CategoryChildListItem> ch = listParent.get(groupPosition).getChildList();
return ch.size();
}
@Override
public Object getGroup(int groupPosition) {
return listParent.get(groupPosition);
}
@Override
public Object getChild(int groupPosition, int childPosition) {
ArrayList<CategoryChildListItem> ch = listParent.get(groupPosition).getChildList();
return ch.get(childPosition);
}
@Override
public long getGroupId(int groupPosition) {
return groupPosition;
}
@Override
public long getChildId(int groupPosition, int childPosition) {
return childPosition;
}
@Override
public boolean hasStableIds() {
return false;
}
@Override
public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {
//CategoryParentItemList parentItem = (CategoryParentItemList)listParent.get(groupPosition);
CategoryParentItemList parentItem = (CategoryParentItemList) getGroup(groupPosition);
ViewHolderGroup holderGroup;
if (convertView == null) {
LayoutInflater infalInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = infalInflater.inflate(R.layout.group_header, null);
holderGroup = new ViewHolderGroup();
holderGroup.lblSubCategoryName = (TextView) convertView.findViewById(R.id.tvItemName);
convertView.setTag(holderGroup);
} else {
holderGroup = (ViewHolderGroup) convertView.getTag();
}
holderGroup.lblSubCategoryName.setText(parentItem.getSubCategoryName());
return convertView;
}
@Override
public View getChildView(int groupPosition,int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {
//final CategoryParentItemList parentItem = (CategoryParentItemList) listParent.get(groupPosition);
//final CategoryChildListItem childItem = (CategoryChildListItem) parentItem.getChildList().get(childPosition);
CategoryChildListItem childItem = (CategoryChildListItem) getChild(groupPosition, childPosition);
ViewHolderChild holder;
if (convertView == null) {
LayoutInflater infalInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = infalInflater.inflate(R.layout.child_row, null);
holder = new ViewHolderChild();
holder.lblItemName = (TextView) convertView.findViewById(R.id.tvSubItemName);
holder.lblDefualtPrice = (TextView) convertView.findViewById(R.id.tvrRupees);
holder.lblQty = (TextView) convertView.findViewById(R.id.tvQty);
holder.imgPlus = (ImageButton) convertView.findViewById(R.id.imageButtonPlus);
holder.imgMinus = (ImageButton) convertView.findViewById(R.id.imageButtonMinus);
convertView.setTag(holder);
} else {
holder = (ViewHolderChild) convertView.getTag();
}
holder.lblItemName.setText(childItem.getSubItemName());
holder.lblDefualtPrice.setText(childItem.getDefaultPrice());
int tmpCount = Integer.parseInt(holder.lblQty.getText().toString());
holder.imgPlus.setOnClickListener(new ClickUpdateListener(childItem,holder, tmpCount));
holder.imgMinus.setOnClickListener(new ClickUpdateListener(childItem, holder, tmpCount));
return convertView;
}
@Override
public boolean isChildSelectable(int groupPosition, int childPosition) {
return true;
}
@Override
public boolean areAllItemsEnabled() {
return true;
}
public static int getTotalCounter() {
return totalCounter;
}
private class ClickUpdateListener implements View.OnClickListener {
ViewHolderChild holder;
public CategoryChildListItem childItem;
//String itemName=null;
//int qty;
//String price;
int counter = 0;
String counterMin;
public ClickUpdateListener(CategoryChildListItem childItem,ViewHolderChild holder, int cnt) {
this.childItem = childItem;
this.holder = holder;
this.counter = cnt;
}
@Override
public void onClick(View v) {
if(v.getId() == R.id.imageButtonPlus) {
counter = counter + 1;
totalCounter+=1;
System.out.println(childItem.getSubItemName()+" : "+childItem.getDefaultPrice() + ": C+ :" + counter);
//here qty increment click on plus button
holder.lblQty.setText(String.format("%d",counter));
notifyDataSetChanged();
}
if(v.getId() == R.id.imageButtonMinus){
counterMin = (String) holder.lblQty.getText();
counter = Integer.parseInt(counterMin.toString().trim());
counterMin = null;
if(counter > 0) {
counter = counter - 1;
totalCounter-=1;
System.out.println(childItem.getSubItemName()+" : "+childItem.getDefaultPrice() + ": C- :" + counter);
//here qty decrement click on minus button
holder.lblQty.setText(String.format("%d", counter));
notifyDataSetChanged();
}else{
Toast.makeText(context,"Qty Zero",Toast.LENGTH_SHORT).show();
}
}
}
}
}
答案 0 :(得分：0)
类似的东西：
public static int getTotalCounter() {
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences( getApplication() );
return prefs.getInt( "count", 0 );
}
private class ClickUpdateListener implements View.OnClickListener {
@Override
public void onClick(View v) {
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences( getApplication() );
int oldCount = prefs.getInt( "count", 0 );
prefs.edit().put( "count", oldCount + 1 ).commit();
}
}