我的StaggeredGridLayoutManager不显示任何内容。 arraylist iList的大小始终为0.我在queryProduct.execute("");中设置了一个断点，我可以观察到方法protected String doInBackground(String... params)永远不会被执行。为什么我的数据集没有加载到这里？
public class OnSale extends CustomFragment
{
/** The product list. */
private ArrayList<Producto> iList;
private QueryProduct queryProduct;
/* (non-Javadoc)
* @see android.support.v4.app.Fragment#onCreateView(android.view.LayoutInflater, android.view.ViewGroup, android.os.Bundle)
*/
@SuppressLint({ "InflateParams", "InlinedApi" })
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState)
{
View v = inflater.inflate(R.layout.on_sale, null);
((MainActivity) getActivity()).toolbar.setTitle("On Sale");
((MainActivity) getActivity()).toolbar.findViewById(
R.id.spinner_toolbar).setVisibility(View.GONE);
/*if(Build.VERSION.SDK_INT>=Build.VERSION_CODES.LOLLIPOP)
{
getActivity().getWindow().addFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_NAVIGATION);
getActivity().getWindow().addFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS);
}*/
setHasOptionsMenu(true);
setupView(v);
return v;
}
/* (non-Javadoc)
* @see com.whatshere.custom.CustomFragment#onClick(android.view.View)
*/
@Override
public void onClick(View v)
{
super.onClick(v);
}
/**
* Setup the view components for this fragment. You write your code for
* initializing the views, setting the adapters, touch and click listeners
* etc.
*
* @param v
* the base view of fragment
*/
private void setupView(View v)
{
RecyclerView recList = (RecyclerView) v.findViewById(R.id.lista_de_productos_on_sale);
loadDummyData();
recList.setHasFixedSize(true);
StaggeredGridLayoutManager llm = new StaggeredGridLayoutManager(2,
StaggeredGridLayoutManager.VERTICAL);
recList.setLayoutManager(llm);
CardAdapter ca = new CardAdapter();
recList.setAdapter(ca);
}
/**
* The Class CardAdapter is the adapter for showing products in Card format
* inside the RecyclerView. It shows dummy product image and dummy contents,
* so you need to display actual contents as per your need.
*/
private class CardAdapter extends
RecyclerView.Adapter<CardAdapter.CardViewHolder>
{
/* (non-Javadoc)
* @see android.support.v7.widget.RecyclerView.Adapter#getItemCount()
*/
@Override
public int getItemCount()
{
return iList.size();
}
/* (non-Javadoc)
* @see android.support.v7.widget.RecyclerView.Adapter#onBindViewHolder(android.support.v7.widget.RecyclerView.ViewHolder, int)
*/
@Override
public void onBindViewHolder(CardViewHolder vh, int i)
{
Producto d = iList.get(i);
vh.lbl1.setText(d.getTexts()[0]);
vh.lbl2.setText(d.getTexts()[1]);
vh.lbl3.setText(d.getTexts()[2]);
vh.img.setImageBitmap(d.getResources());
}
/* (non-Javadoc)
* @see android.support.v7.widget.RecyclerView.Adapter#onCreateViewHolder(android.view.ViewGroup, int)
*/
@Override
public CardViewHolder onCreateViewHolder(ViewGroup viewGroup, int i)
{
View itemView = LayoutInflater.from(viewGroup.getContext())
.inflate(R.layout.grid_item, viewGroup, false);
itemView.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v)
{
startActivity(new Intent(getActivity(), ProductDetail.class));
}
});
return new CardViewHolder(itemView);
}
/**
* The Class CardViewHolder is the View Holder class for Adapter views.
*/
public class CardViewHolder extends RecyclerView.ViewHolder
{
/** The lbl3. */
protected TextView lbl1, lbl2, lbl3;
/** The img. */
protected ImageView img;
/**
* Instantiates a new card view holder.
*
* @param v
* the v
*/
public CardViewHolder(View v)
{
super(v);
lbl1 = (TextView) v.findViewById(R.id.lbl1);
lbl2 = (TextView) v.findViewById(R.id.lbl2);
lbl3 = (TextView) v.findViewById(R.id.lbl3);
img = (ImageView) v.findViewById(R.id.img);
}
}
}
/**
* Load dummy product data for displaying on the RecyclerView. You need to
* write your own code for loading real products from Web-service or API and
* displaying them on RecyclerView.
*/
private void loadDummyData()
{
iList= new ArrayList<Producto>();
queryProduct =new QueryProduct();
queryProduct.execute("");
}
/* (non-Javadoc)
* @see android.support.v4.app.Fragment#onCreateOptionsMenu(android.view.Menu, android.view.MenuInflater)
*/
@Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater)
{
inflater.inflate(R.menu.search_exp, menu);
menu.findItem(R.id.menu_grid).setVisible(false);
super.onCreateOptionsMenu(menu, inflater);
}
class QueryProduct extends AsyncTask<String, Void, String> {
ArrayList<Producto> alistaDeProductos=new ArrayList<Producto>();
@Override
protected String doInBackground(String... params) {
String result = "";
String s = "";
InputStream isr = null;
try {
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://aaaaa/app/getAllCustomers.php"); // YOUR PHP
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
isr = 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(isr, "iso-8859-1"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
isr.close();
result = sb.toString();
} catch (Exception e) {
Log.e("log_tag", "Error converting result " + e.toString());
}
// parse json data
try {
JSONArray jArray = new JSONArray(result);
Integer size=jArray.length();
for (int i = 0; i < jArray.length(); i++) {
JSONObject json = jArray.getJSONObject(i);
InputStream in = new java.net.URL(json.getString("imagen")).openStream();
Bitmap loadedImage= BitmapFactory.decodeStream(in);
//
Producto producto=new Producto(new String[]{"50",json.getString("descripcion"),json.getString("preciodia"),json.getString("marca")},loadedImage);
iList.add(producto);
}
} catch (JSONException e) {
Log.e("Error", e.getMessage());
e.printStackTrace();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return s;
}
}
}
答案 0 :(得分：0)
我可以找到我的错误。我需要通知我的适配器，在这种情况下称为CardAdapter，差异更改。这可以通过方法notifyDataSetChanged()来实现。加载数据集后应使用adapter.notifyDataSetChanged()。
如果您想了解更多信息，可以访问此链接RecyclerView Adapter and ViewHolder update dynamically
此处我的更正后的代码
public class OnSale extends CustomFragment
{
/** The product list. */
private ArrayList<Producto> iList;
private QueryProduct queryProduct;
CardAdapter ca = new CardAdapter();
/* (non-Javadoc)
* @see android.support.v4.app.Fragment#onCreateView(android.view.LayoutInflater, android.view.ViewGroup, android.os.Bundle)
*/
@SuppressLint({ "InflateParams", "InlinedApi" })
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState)
{
View v = inflater.inflate(R.layout.on_sale, null);
((MainActivity) getActivity()).toolbar.setTitle("On Sale");
((MainActivity) getActivity()).toolbar.findViewById(
R.id.spinner_toolbar).setVisibility(View.GONE);
/*if(Build.VERSION.SDK_INT>=Build.VERSION_CODES.LOLLIPOP)
{
getActivity().getWindow().addFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_NAVIGATION);
getActivity().getWindow().addFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS);
}*/
setHasOptionsMenu(true);
setupView(v);
return v;
}
/* (non-Javadoc)
* @see com.whatshere.custom.CustomFragment#onClick(android.view.View)
*/
@Override
public void onClick(View v)
{
super.onClick(v);
}
/**
* Setup the view components for this fragment. You write your code for
* initializing the views, setting the adapters, touch and click listeners
* etc.
*
* @param v
* the base view of fragment
*/
private void setupView(View v)
{
RecyclerView recList = (RecyclerView) v.findViewById(R.id.lista_de_productos_on_sale);
recList.setHasFixedSize(true);
StaggeredGridLayoutManager llm = new StaggeredGridLayoutManager(2,
StaggeredGridLayoutManager.VERTICAL);
recList.setLayoutManager(llm);
loadDummyData();
recList.setAdapter(ca);
}
/**
* The Class CardAdapter is the adapter for showing products in Card format
* inside the RecyclerView. It shows dummy product image and dummy contents,
* so you need to display actual contents as per your need.
*/
private class CardAdapter extends
RecyclerView.Adapter<CardAdapter.CardViewHolder>
{
/* (non-Javadoc)
* @see android.support.v7.widget.RecyclerView.Adapter#getItemCount()
*/
@Override
public int getItemCount()
{
return iList.size();
}
/* (non-Javadoc)
* @see android.support.v7.widget.RecyclerView.Adapter#onBindViewHolder(android.support.v7.widget.RecyclerView.ViewHolder, int)
*/
@Override
public void onBindViewHolder(CardViewHolder vh, int i)
{
Producto d = iList.get(i);
vh.lbl1.setText(d.getTexts()[0]);
vh.lbl2.setText(d.getTexts()[1]);
vh.lbl3.setText(d.getTexts()[2]);
vh.img.setImageBitmap(d.getResources());
}
/* (non-Javadoc)
* @see android.support.v7.widget.RecyclerView.Adapter#onCreateViewHolder(android.view.ViewGroup, int)
*/
@Override
public CardViewHolder onCreateViewHolder(ViewGroup viewGroup, int i)
{
View itemView = LayoutInflater.from(viewGroup.getContext())
.inflate(R.layout.grid_item, viewGroup, false);
itemView.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v)
{
startActivity(new Intent(getActivity(), ProductDetail.class));
}
});
return new CardViewHolder(itemView);
}
/**
* The Class CardViewHolder is the View Holder class for Adapter views.
*/
public class CardViewHolder extends RecyclerView.ViewHolder
{
/** The lbl3. */
protected TextView lbl1, lbl2, lbl3;
/** The img. */
protected ImageView img;
/**
* Instantiates a new card view holder.
*
* @param v
* the v
*/
public CardViewHolder(View v)
{
super(v);
lbl1 = (TextView) v.findViewById(R.id.lbl1);
lbl2 = (TextView) v.findViewById(R.id.lbl2);
lbl3 = (TextView) v.findViewById(R.id.lbl3);
img = (ImageView) v.findViewById(R.id.img);
}
}
}
/**
* Load dummy product data for displaying on the RecyclerView. You need to
* write your own code for loading real products from Web-service or API and
* displaying them on RecyclerView.
*/
private void loadDummyData()
{
iList= new ArrayList<Producto>();
queryProduct =new QueryProduct();
queryProduct.execute("");
}
/* (non-Javadoc)
* @see android.support.v4.app.Fragment#onCreateOptionsMenu(android.view.Menu, android.view.MenuInflater)
*/
@Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater)
{
inflater.inflate(R.menu.search_exp, menu);
menu.findItem(R.id.menu_grid).setVisible(false);
super.onCreateOptionsMenu(menu, inflater);
}
class QueryProduct extends AsyncTask<String, Void, String> {
ArrayList<Producto> alistaDeProductos=new ArrayList<Producto>();
@Override
protected String doInBackground(String... params) {
String result = "";
String s = "";
InputStream isr = null;
try {
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://aaa.php"); // YOUR PHP
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
isr = 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(isr, "iso-8859-1"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
isr.close();
result = sb.toString();
} catch (Exception e) {
Log.e("log_tag", "Error converting result " + e.toString());
}
// parse json data
try {
JSONArray jArray = new JSONArray(result);
for (int i = 0; i < jArray.length(); i++) {
JSONObject json = jArray.getJSONObject(i);
InputStream in = new java.net.URL(json.getString("imagen")).openStream();
Bitmap loadedImage= BitmapFactory.decodeStream(in);
//
Producto producto=new Producto(new String[]{"50",json.getString("descripcion"),json.getString("preciodia"),json.getString("marca")},loadedImage);
iList.add(producto);
}
} catch (JSONException e) {
Log.e("Error", e.getMessage());
e.printStackTrace();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return s;
}
@Override
protected void onPostExecute(String s) {
ca.notifyDataSetChanged();
}
}
}