我有一个显示产品的列表视图（产品名称，产品价格和产品描述）。 我想在webview中显示产品描述，因为我使用HTML代码（图像，表格，视频等）。
除了WebView上的产品说明外，产品列表上的所有内容都可以。 当我在不可见的产品上滚动列表视图时，产品描述（WebView）完全错误，实际上它显示了以前产品的描述。
问题出在GetView函数中，虽然我使用了一个viewHolder类，但仍然存在重新发送问题的问题。下面我展示了Getview的代码片段和viewholder类：
/////提供UI组件的视图类//////////////////
private class ViewHolder {
TextView prName;
WebView prDescription;
TextView product_descr2;//for test, this shows always the correct pr. descr.
TextView prfprice;
ImageView prImage;
ProgressBar prProgressBar;
int ProdPosition;
}
////// GETVIEW（）功能，我在哪里加载每个产品价值///////
@Override
public View getView(int position, View convertView, ViewGroup parent) {
final ViewHolder viewHolder;
View view = convertView;
final ProductsData info = getItem(position);
if (view == null) {
// Product row
view = mInflater.inflate(R.layout.productslistitem_layout, null);
viewHolder = new ViewHolder();
assert view != null;
viewHolder.prName = (TextView) view.findViewById(R.id.product_name);
viewHolder.prDescription = (WebView) view.findViewById(R.id.webView1);
viewHolder.product_descr2 = (TextView)view.findViewById(R.id.product_descr2);
viewHolder.prDescription.setFocusable(false);
//final price
viewHolder.prfprice = (TextView) view.findViewById(R.id.product_fprice);
viewHolder.prImage = (ImageView) view.findViewById(R.id.product_image);
viewHolder.prProgressBar = (ProgressBar)view.findViewById(R.id.pbProduct);
view.setTag(viewHolder);
}else
viewHolder = (ViewHolder) view.getTag();
MainActivity.imageLoaderProducts.displayImage(info.getPrUrl(), viewHolder.prImage, options, new SimpleImageLoadingListener(){
@Override
public void onLoadingStarted(String imageUri, View view) {
viewHolder.prProgressBar.setProgress(0);
viewHolder.prProgressBar.setVisibility(View.VISIBLE);
}
@Override
public void onLoadingFailed(String imageUri, View view,
FailReason failReason) {
viewHolder.prProgressBar.setVisibility(View.GONE);
}
@Override
public void onLoadingComplete(String imageUri, View view, Bitmap loadedImage) {
viewHolder.prProgressBar.setVisibility(View.GONE);
viewHolder.prName.setText(info.getPrName()); //PRODUCT NAME
viewHolder.product_descr2.setText(info.getPrDescr()));//PRODUCT DESCR, CORRECT VALUES
String header = "<?xml version=\"1.0\" encoding=\"UTF-8\" ?>";
viewHolder.prDescription.setWebViewClient(new WebViewClient());
viewHolder.prDescription.getSettings().setJavaScriptEnabled(true);
//ENCODING UTF-8
viewHolder.prDescription.getSettings().setDefaultTextEncodingName("utf-8");
viewHolder.prDescription.loadData(header +"<div style='background-color:#fff'>"+ info.getPrDescr()+"</div>", "text/html; charset=utf-8", null);//WBVIEW SHOW WRONG PR.DESCR.
}, new ImageLoadingProgressListener() {
@Override
public void onProgressUpdate(String imageUri, View view, int current,int total) {
viewHolder.prProgressBar.setProgress(Math.round(100.0f * current / total));
}
}
);
return view;
}
product_descr2（TextView）显示正确的产品说明，但prDescription（WebView）仅显示列表的第一个产品的正确说明。这是WebView组件的错误还是我做错了什么？
如果有人知道任何解决方案，请伸出援手。
/ ******** /
我注意到如果我添加convertview = null;在getView中，它将正确的值加载到WebViews中，但速度太慢。 我显示产品文件的代码。我使用通用图像加载器来延迟加载产品图像。
/ ******************产品档案************************** ********************************** /
import java.util.ArrayList;
public class FragmentProducts extends Fragment implements
OnItemClickListener {
private ArrayList<ProductsData> productsList;
private ArrayList<ProductBitmapData> ProductBitmapList;
private LayoutInflater mInflater;
private ProductsListAdapter pAdapter;
private GridView lvProducts;
private ImageButton btnRefreshProducts;
private String VarTitle;//vartitle for the cart
private String VarId;//varId for the cart
private float VarPrice;//varPrice for the cart
//NEW for universal image loader
private DisplayImageOptions options;
@Override
public void onViewCreated(View view, Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onViewCreated(view, savedInstanceState);
//change fonts
TextView tvProductsHeader = (TextView)getActivity().findViewById(R.id.tvProductsHeader);
Utils.TypeFace(tvProductsHeader, getActivity().getAssets());
}
@Override
public void onActivityCreated(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onActivityCreated(savedInstanceState);
mInflater = getActivity().getLayoutInflater();
pAdapter = new ProductsListAdapter(getActivity(), productsList);
lvProducts.setAdapter(pAdapter);
}
public static final FragmentProducts newInstance(
ArrayList<ProductsData> productsList,
ArrayList<ProductBitmapData> ProductBitmapList) {
FragmentProducts fr = new FragmentProducts();
Bundle args = new Bundle();
args.putSerializable("products", productsList);
args.putSerializable("bitmaps", ProductBitmapList);
fr.setArguments(args);
return fr;
}
public static final FragmentProducts newInstance(
ArrayList<ProductsData> productsList) {
//OLD FragmentProductsList fr = new FragmentProductsList();
FragmentProducts fr = new FragmentProducts();
Bundle args = new Bundle();
args.putSerializable("products", productsList);
fr.setArguments(args);
return fr;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
this.productsList = (ArrayList<ProductsData>) (getArguments() != null ? getArguments()
.getSerializable("products") : null);
this.ProductBitmapList = (ArrayList<ProductBitmapData>) (getArguments() != null ? getArguments()
.getSerializable("bitmaps") : null);
//display options
options = new DisplayImageOptions.Builder()
.showImageOnLoading(R.drawable.ic_stub)
.showImageForEmptyUri(R.drawable.ic_empty)
.showImageOnFail(R.drawable.ic_error)
.cacheInMemory(true)
.cacheOnDisk(true)
.considerExifParams(true)
.bitmapConfig(Bitmap.Config.RGB_565)
.build();
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.productslist_layout, container,
false);
lvProducts = (GridView) view.findViewById(R.id.glist);
lvProducts.setOnItemClickListener(this);
btnRefreshProducts = (ImageButton) view
.findViewById(R.id.btnRefreshProducts);
btnRefreshProducts.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
pAdapter = new ProductsListAdapter(getActivity(), productsList);
lvProducts.setAdapter(pAdapter);
}
});
return view;
}
// CUSTOM ARRAY ADAPTER FOR THE LIST of CATEGORY ITEMS
public class ProductsListAdapter extends ArrayAdapter<ProductsData> {
public ProductsListAdapter(Context context, ArrayList<ProductsData> data) {
super(context, 0, data);
}
private class ViewHolder {
TextView prName;
WebView prDescription;
TextView prfprice;
ImageView prImage;
ProgressBar prProgressBar;
Spinner PrVariants1;
Spinner PrVariants2;
int ProdPosition;
//adapters
ArrayAdapter<String> var1Adapter;
ArrayAdapter<String> var2Adapter;
}
@Override
public int getCount() {
return super.getCount();
}
@Override
public ProductsData getItem(int position) {
return super.getItem(position);
}
@Override
public long getItemId(int position) {
return super.getItemId(position);
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
final ViewHolder viewHolder;
/*Clear convert view , and the WEBVIEW(DESCRIPTION) WORKS FINE! **/
/*BUT IT IS TOO SLOW BECAUSE, IT LOADS FROM THE START EACH TIME*/
convertView = null;
/*************************/
View view = convertView;
final ProductsData info = getItem(position);
if (view == null) {
// Product row
view = mInflater.inflate(R.layout.productslistitem_layout, null);
viewHolder = new ViewHolder();
assert view != null;
viewHolder.prName = (TextView) view.findViewById(R.id.product_name);
viewHolder.prDescription = (WebView) view.findViewById(R.id.webView1);
viewHolder.prDescription.setFocusable(false);
//starting price
/*viewHolder.prsprice = (TextView) view.findViewById(R.id.product_sprice);*/
//final price
viewHolder.prfprice = (TextView) view.findViewById(R.id.product_fprice);
viewHolder.prImage = (ImageView) view.findViewById(R.id.product_image);
viewHolder.prProgressBar = (ProgressBar)view.findViewById(R.id.pbProduct);
viewHolder.PrVariants1 = (Spinner) view.findViewById(R.id.spOptions1);
viewHolder.PrVariants1.setFocusable(false);
viewHolder.PrVariants2 = (Spinner) view.findViewById(R.id.spOptions2);
viewHolder.PrVariants2.setFocusable(false);
view.setTag(viewHolder);
}else
viewHolder = (ViewHolder) view.getTag();
MainActivity.imageLoaderProducts.displayImage(info.getPrUrl(), viewHolder.prImage, options, new SimpleImageLoadingListener(){
@Override
public void onLoadingStarted(String imageUri, View view) {
viewHolder.prProgressBar.setProgress(0);
viewHolder.prProgressBar.setVisibility(View.VISIBLE);
}
@Override
public void onLoadingFailed(String imageUri, View view,
FailReason failReason) {
viewHolder.prProgressBar.setVisibility(View.GONE);
}
@Override
public void onLoadingComplete(String imageUri, View view, Bitmap loadedImage) {
viewHolder.prProgressBar.setVisibility(View.GONE);
viewHolder.prName.setText(info.getPrName());
//SHOW WEBVIEW PRODUCT VALUE
String header = "<?xml version=\"1.0\" encoding=\"UTF-8\" ?>";
viewHolder.prDescription.setWebViewClient(new WebViewClient());
viewHolder.prDescription.getSettings().setJavaScriptEnabled(true);
//ENCODING UTF-8
viewHolder.prDescription.getSettings().setDefaultTextEncodingName("utf-8");
/**HERE IS THE PROBLEM ,I LOAD THE info.PrComments(product description)*/
viewHolder.prDescription.loadData(header +"<div style='background-color:#fff'>"+ info.getPrComments()+"</div>", "text/html; charset=utf-8", null);
/****************AND IF I SCROLL THE WEBVIEW VALUES ARE CONFUSED ***********/
/********START FILL VARIANTS 1 & 2***********/
viewHolder.var1Adapter = new ArrayAdapter<String>(getActivity(),android.R.layout.simple_spinner_item);
viewHolder.var2Adapter = new ArrayAdapter<String>(getActivity(), android.R.layout.simple_spinner_item);
//product id
int tempPrid = info.getPrID();
//new variants1
//LOAD variant1
for(int i = 0; i < info.getVariantsItems().size(); i ++){
viewHolder.var1Adapter.add(info.getVariantsItems().get(i).getVarOptions1());
}
//IF VARIANT2 IS NULL, View.GONE
if(info.getVariantsItems2().get(0).getVarOptions2() != null){
for(int i = 0; i < info.getVariantsItems2().size(); i ++){
viewHolder.var2Adapter.add(info.getVariantsItems2().get(i).getVarOptions2());
}
viewHolder.var2Adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
viewHolder.PrVariants2.setAdapter(viewHolder.var2Adapter);
}//end if
else{
viewHolder.PrVariants2.setVisibility(View.GONE);
}//end else variant2
viewHolder.var1Adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
viewHolder.PrVariants1.setAdapter(viewHolder.var1Adapter);
//add eventListener on variants1 listbox
viewHolder.PrVariants1.setOnItemSelectedListener(new OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent,
View arg1, int pos, long arg3) {
//GET VALUES FROM spinner1
String tempOption1 = parent.getItemAtPosition(pos).toString();
//initialize
String tempOption2=null;
//CHECK IF SPINNER2 IS VISIBLE(IF IT IS VISIBLE ,IT HAS VALUE)
if (viewHolder.PrVariants2.getVisibility() != View.GONE){
if (viewHolder.PrVariants2.getSelectedItem() != null){
tempOption2 = viewHolder.PrVariants2.getSelectedItem().toString();
}
}
if (tempOption2 !=null)
{
VarTitle = tempOption1 + "/" + tempOption2;
}else
VarTitle = tempOption1;
ArrayList<String> res = MainApplication.dbHelper.checkVariation(VarTitle, Integer.toString(info.getPrID()));
//IF VARIATION DOES NOT EXIST , price field = N/A
if (res.isEmpty())
viewHolder.prfprice.setText("N/A");
else{
viewHolder.prfprice.setText(res.get(1) + "€");
VarId = res.get(0);//get the variantId for the cart
VarPrice = Float.valueOf(res.get(1));//get the variant price for the cart
}
}
@Override
public void onNothingSelected(AdapterView<?> arg0) {}
});
//add event listener on variants2 listbox
viewHolder.PrVariants2.setOnItemSelectedListener(new OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent,
View arg1, int pos, long arg3) {
//initialize
String tempOption2 = null;
if(parent.getItemAtPosition(pos) != null){
tempOption2 = parent.getItemAtPosition(pos).toString();
}
//GET SPINNER1 VALUE
String tempOption1 = viewHolder.PrVariants1.getSelectedItem().toString();
if(tempOption2 != null)
{
VarTitle = tempOption1 + "/" + tempOption2;
}else
VarTitle = tempOption1;
ArrayList<String> res = MainApplication.dbHelper.checkVariation(VarTitle, Integer.toString(info.getPrID()));
///IF VARIATION DOES NOT EXIST , price field = N/A
if (res.isEmpty())
viewHolder.prfprice.setText("N/A");
else{
viewHolder.prfprice.setText(res.get(1) + "€");
VarId = res.get(0);//get the variantId for the cart
VarPrice = Float.valueOf(res.get(1));//get the variant price for the cart
}
}
@Override
public void onNothingSelected(AdapterView<?> arg0) {}
});
/********END FILL VARIANTS 1 & 2*************/
}
}, new ImageLoadingProgressListener() {
@Override
public void onProgressUpdate(String imageUri, View view, int current,
int total) {
viewHolder.prProgressBar.setProgress(Math.round(100.0f * current / total));
}
}
);
return view;
}
}
答案 0 :(得分：2)
不要使用ViewHolder！ =＆GT; http://blog.xebia.com/2013/07/22/viewholder-considered-harmful/
试试这个：
...没有 if（convert == null）{ ....
只需充气 convertView
@Override
public View getView(int position, View convertView, ViewGroup parent) {
convertView = Inflater.inflate(R.layout.productslistitem_layout, null);
...
...