Question

我正在使用Retrofit / Picasso / Recyclerview的组合将图像加载到GridLayoutManager中。我有一个搜索栏，用户输入一个术语来查询FlickR并根据搜索词填充结果。

问题是我想假设用户可能想要重新搜索不同的术语。如果是这种情况，我想清除RecyclerView，重新查询FlickR，然后将图像重新填充到RecyclerView中。看起来像很多活动，我相信有一种简单的方法可以实现：

public class NewImageActivity extends AppCompatActivity {

private SearchView mSearchView;
private RecyclerView mImageResults;
private RecyclerView.Adapter mImageResultsAdapter;
private ArrayList<Photo> mPhotoArray;
private ArrayList<String> mPhotoURLS;


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_new_image);
    if(getSupportActionBar() != null){
        getSupportActionBar().setDisplayHomeAsUpEnabled(false);
    }

    mImageResults = (RecyclerView) findViewById(R.id.flickr_image_results_view);
    GridLayoutManager glm = new GridLayoutManager(this, 2);
    glm.setOrientation(LinearLayoutManager.VERTICAL);
    mImageResults.setLayoutManager(glm);
    mImageResults.setItemAnimator(new DefaultItemAnimator());
    mImageResultsAdapter = new MyAdapter(mPhotoURLS);
    mImageResults.setAdapter(mImageResultsAdapter);
    int spanCount = 2; // 3 columns
    int spacing = 25; // 50px
    boolean includeEdge = false;
    mImageResults.addItemDecoration(new GridSpacingItemDecoration(spanCount, spacing, includeEdge));
    mPhotoURLS = new ArrayList<>();
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.menu_search, menu);
    // Retrieve the SearchView and plug it into SearchManager
    MenuItem searchItem = menu.findItem(R.id.search);
    final SearchView searchView = (SearchView) MenuItemCompat.getActionView(searchItem);
    searchItem.expandActionView();
    MenuItemCompat.setOnActionExpandListener(searchItem, new MenuItemCompat.OnActionExpandListener() {
        @Override
        public boolean onMenuItemActionExpand(MenuItem item) {
            Toast.makeText(getApplicationContext(), "Open", Toast.LENGTH_LONG).show();
            return true;
        }

        @Override
        public boolean onMenuItemActionCollapse(MenuItem item) {
            Toast.makeText(getApplicationContext(), "Back_Press", Toast.LENGTH_LONG).show();
            finish();
            return true;
        }
    });
    searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
        @Override
        public boolean onQueryTextSubmit(String query) {
            View view = getCurrentFocus();
            if (view != null) {
                InputMethodManager imm = (InputMethodManager)getSystemService(Context.INPUT_METHOD_SERVICE);
                imm.hideSoftInputFromWindow(view.getWindowToken(), 0);
            }
            //the urls to populate the Recyclerview; URLs dumped into Picasso
            mPhotoURLS.clear();
            mImageResultsAdapter.notifyDataSetChanged();
            Toast.makeText(getApplicationContext(), query, Toast.LENGTH_LONG).show();
            HttpLoggingInterceptor interceptor = new HttpLoggingInterceptor();
            interceptor.setLevel(HttpLoggingInterceptor.Level.BODY);
            OkHttpClient client = new OkHttpClient.Builder().addInterceptor(interceptor).build();
            Retrofit retrofit = new Retrofit.Builder()
                    .baseUrl("https://api.flickr.com/services/rest/")
                    .client(client)
                    .addConverterFactory(GsonConverterFactory.create())
                    .build();


            ApiInterface apiInterface = retrofit.create(ApiInterface.class);
            Call<Flicker> call = apiInterface.getImages(query);
            call.enqueue(new Callback<Flicker>() {
                @Override
                public void onResponse(Call<Flicker> call, Response<Flicker> response) {
                    Log.v("RESPONSE_CALLED", "ON_RESPONSE_CALLED");
                    String didItWork = String.valueOf(response.isSuccessful());
                    Log.v("SUCCESS?", didItWork);
                    Log.v("RESPONSE_CODE", String.valueOf(response.code()));
                    Flicker testResponse = response.body();
                    Log.v("RESPONSE_BODY", "response:" + testResponse);
                    String total = response.body().getPhotos().getTotal().toString();
                    Log.v("Total", total);
                    List<Photo> photoResults = response.body().getPhotos().getPhoto();
                    int numberOfPages = response.body().getPhotos().getPages();
                    for (int i = 0; i < numberOfPages; i++) {
                        for (Photo photo : photoResults) {
                            if (photo.getUrl_m() != null) {
                                String photoURL = photo.getUrl_m();
                                Log.v("PHOTO_URL:", photoURL);
                                mPhotoURLS.add(photoURL);
                                mImageResultsAdapter.notifyDataSetChanged();
                            }
                        }


                    }

                }

                @Override
                public void onFailure(Call<Flicker> call, Throwable t) {

                }
            });
            return true;
        }

        @Override
        public boolean onQueryTextChange(String newText) {
            return false;
        }
    });

    return true;
}


public class MyAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder> {




    // Provide a reference to the views for each data item
    // Complex data items may need more than one view per item, and
    // you provide access to all the views for a data item in a view holder
    public class ViewHolder extends RecyclerView.ViewHolder {
        // each data item is just a string in this case
        protected ImageView mResultImage;


        public ViewHolder(View v) {
            super(v);
            mResultImage = (ImageView) v.findViewById(R.id.flickr_individual_image);


        }
    }

    // Provide a suitable constructor (depends on the kind of dataset)
    public MyAdapter(ArrayList<String> mDataSet) {
        mPhotoURLS = mDataSet;
    }

    // Create new views (invoked by the layout manager)
    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent,
                                         int viewType) {
        // create a new view
        View v = LayoutInflater.from(parent.getContext())
                .inflate(R.layout.grid_item, parent, false);
        // set the view's size, margins, paddings and layout parameters
        return new ViewHolder(v);
    }

    // Replace the contents of a view (invoked by the layout manager)

    //The OutOfBoundsException is pointing here
    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {
        Log.v("ON_BIND", "ON_BINDVIEWHOLDER CALLED");
        String urlForPhoto = mPhotoURLS.get(position);
        Picasso.with(getApplicationContext())
                .load(urlForPhoto)
                .placeholder( R.drawable.progress_animation )
                .into(holder.mResultImage);

    }

    // Return the size of your dataset (invoked by the layout manager)
    @Override
    public int getItemCount() {
        return mPhotoURLS.size();
    }
}

public void clearData() {
    int size = this.mPhotoURLS.size();
    if (size > 0) {
        for (int i = 0; i < size; i++) {
            this.mPhotoURLS.remove(0);
        }

        mImageResultsAdapter.notifyItemRangeRemoved(0, size);
    }
}

public interface ApiInterface {

    @GET("?method=flickr.photos.search&api_key=1c448390199c03a6f2d436c40defd90e&format=json&nojsoncallback=1&extras=url_m")
    Call<Flicker> getImages(@Query("text") String query);

}

Answer 1

收到新回复后，清除现有数据，用新数据更新列表，最后调用适配器上的notifydatasetchanged。

    mPhotoURLS.clear();
    for (int i = 0; i < numberOfPages; i++) {
        for (Photo photo : photoResults) {
            if (photo.getUrl_m() != null) {
                String photoURL = photo.getUrl_m();
                Log.v("PHOTO_URL:", photoURL);
                mPhotoURLS.add(photoURL);                    
            }
        }
    }
    mImageResultsAdapter.notifyDataSetChanged();

重置/清除RecylerView

1 个答案: