为了获取图像并在回收站视图中显示它我使用了volley imageloader，
Pic_class.java
public class Pic_class {
//Data Variables
private String url;
private String name;
//Getters and Setters
public String geturl() {
return url;
}
public void seturl(String imageUrl) {
this.url = imageUrl;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
CardAdapter.java
public class CardAdapter extends RecyclerView.Adapter<CardAdapter.ViewHolder> {
//Imageloader to load image
private ImageLoader imageLoader;
private Context context;
//List to store all superheroes
List<Pic_class> superHeroes;
//Constructor of this class
public CardAdapter(List<Pic_class> superHeroes, Context context){
super();
//Getting all superheroes
this.superHeroes = superHeroes;
this.context = context;
}
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View v = LayoutInflater.from(parent.getContext())
.inflate(R.layout.pic_recycler, parent, false);
ViewHolder viewHolder = new ViewHolder(v);
return viewHolder;
}
@Override
public void onBindViewHolder(ViewHolder holder, int position) {
//Getting the particular item from the list
Pic_class superHero = superHeroes.get(position);
Log.i("superHero(position)",superHero.geturl());
//Loading image from url
imageLoader = CustomVolleyRequest.getInstance(context).getImageLoader();
imageLoader.get(superHero.geturl(),
ImageLoader.getImageListener(
holder.imageView,
R.drawable.exit,
android.R.drawable.ic_dialog_alert));
Log.i("imageLoader",imageLoader.toString());
//Showing data on the views
holder.imageView.setImageUrl(superHero.geturl(), imageLoader);
holder.textViewName.setText(superHero.getName());
//holder.textViewPublisher.setText(superHero.getPublisher());
}
@Override
public int getItemCount() {
return superHeroes.size();
}
class ViewHolder extends RecyclerView.ViewHolder{
//Views
public NetworkImageView imageView;
public TextView textViewName;
// public TextView textViewPublisher;
//Initializing Views
public ViewHolder(View itemView) {
super(itemView);
imageView = (NetworkImageView) itemView.findViewById(R.id.imageViewHero);
textViewName = (TextView) itemView.findViewById(R.id.textViewName);
// textViewPublisher = (TextView) itemView.findViewById(R.id.textViewPublisher);
}
}
}
Last_pics.java
public class Last_pics extends Fragment /*implements RecyclerView.OnScrollChangeListener*/{
//Data URL
public static final String DATA_URL = "http://10.0.3.2:90/android/pic_list.php?page=";
//JSON TAGS
public static final String TAG_TEN = "ten";
public static final String TAG_URL = "url";
//Creating a List of superheroes
private List<Pic_class> listSuperHeroes;
//Creating Views
private RecyclerView recyclerView;
private RecyclerView.LayoutManager layoutManager;
private RecyclerView.Adapter adapter;
//Volley Request Queue
private RequestQueue requestQueue;
//The request counter to send ?page=1, ?page=2 requests
private int requestCount = 1;
LinearLayout ll;
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
/** Inflating the layout for this fragment **/
ll = (LinearLayout) inflater.inflate(R.layout.last_pics, container, false);
//Initializing Views
recyclerView = (RecyclerView) ll.findViewById(R.id.recyclerView);
recyclerView.setHasFixedSize(true);
layoutManager = new LinearLayoutManager(getActivity());
recyclerView.setLayoutManager(layoutManager);
//Initializing our superheroes list
listSuperHeroes = new ArrayList<>();
requestQueue = Volley.newRequestQueue(getActivity());
//Calling method to get data to fetch data
getData();
//Adding an scroll change listener to recyclerview
// recyclerView.setOnScrollChangeListener(this);
//initializing our adapter
adapter = new CardAdapter(listSuperHeroes, getActivity());
//Adding adapter to recyclerview
recyclerView.setAdapter(adapter);
return ll;
}
//Request to get json from server we are passing an integer here
//This integer will used to specify the page number for the request ?page = requestcount
//This method would return a JsonArrayRequest that will be added to the request queue
private JsonArrayRequest getDataFromServer(int requestCount) {
//Initializing ProgressBar
final ProgressBar progressBar = (ProgressBar) ll.findViewById(R.id.progressBar1);
//Displaying Progressbar
progressBar.setVisibility(View.VISIBLE);
getActivity().setProgressBarIndeterminateVisibility(true);
//JsonArrayRequest of volley
JsonArrayRequest jsonArrayRequest = new JsonArrayRequest(DATA_URL + String.valueOf(requestCount),
new Response.Listener<JSONArray>() {
@Override
public void onResponse(JSONArray response) {
//Calling method parseData to parse the json response
parseData(response);
//Hiding the progressbar
progressBar.setVisibility(View.GONE);
}
},
new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
progressBar.setVisibility(View.GONE);
//If an error occurs that means end of the list has reached
Toast.makeText(getActivity(), "No More Items Available", Toast.LENGTH_SHORT).show();
}
});
//Returning the request
return jsonArrayRequest;
}
//This method will get data from the web api
private void getData() {
//Adding the method to the queue by calling the method getDataFromServer
requestQueue.add(getDataFromServer(requestCount));
//Incrementing the request counter
requestCount++;
}
//This method will parse json data
private void parseData(JSONArray array) {
for (int i = 0; i < array.length(); i++) {
//Creating the superhero object
Pic_class superHero = new Pic_class();
JSONObject json = null;
try {
//Getting json
json = array.getJSONObject(i);
//Adding data to the superhero object
superHero.seturl(json.getString(TAG_URL));
superHero.setName(json.getString(TAG_TEN));
Log.i("dooghaie",superHero.getName()+superHero.geturl());
//superHero.setPublisher(json.getString(Config.TAG_PUBLISHER));
} catch (JSONException e) {
e.printStackTrace();
}
//Adding the superhero object to the list
listSuperHeroes.add(superHero);
}
//Notifying the adapter that data has been added or changed
adapter.notifyDataSetChanged();
}
//This method would check that the recyclerview scroll has reached the bottom or not
private boolean isLastItemDisplaying(RecyclerView recyclerView) {
if (recyclerView.getAdapter().getItemCount() != 0) {
int lastVisibleItemPosition = ((LinearLayoutManager) recyclerView.getLayoutManager()).findLastCompletelyVisibleItemPosition();
if (lastVisibleItemPosition != RecyclerView.NO_POSITION && lastVisibleItemPosition == recyclerView.getAdapter().getItemCount() - 1)
return true;
}
return false;
}
}
但是在运行中，在模拟器中，在recyclerview中，只有在imageview中有android.R.drawable.ic_dialog_alert 而不是数据库中的图像。 怎么了？为什么它不显示数据库中的图像？