Parse.com RecyclerView不显示图像

Question

我在Parse.com上有一个RecyclerView来显示一个类，但图片没有加载。

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    recipes = new ArrayList<Recipe>();
    connManager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
    mWifi = connManager.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
    mInternet = connManager.getNetworkInfo(ConnectivityManager.TYPE_MOBILE);
    //Parse.enableLocalDatastore(getApplicationContext());

    // Enable Local Datastore.
    if(mWifi.isConnected() && count == 0) {
        Log.d("Invoke order","first if");
        //Parse.initialize(getApplicationContext(), "HX6n9WMdhKg5BPhC7d22IKHV34jyTst5OHQxtxUD", "U9DotgCbByVP4eZ9oFae61w3Hnno0xFUgefYJOq4");
        ParseQuery<ParseObject> query = ParseQuery.getQuery("Collection");
        progressDialog = ProgressDialog.show(ListActivity.this, "",
                "Update", true);

        query.findInBackground(new FindCallback<ParseObject>() {
            public void done(List<ParseObject> recipesList, ParseException e) {
                if (e == null) {

                    ParseObject.pinAllInBackground(recipesList);
                    Log.d("score", "Retrieved " + recipesList.size() + " recipes");
                    for ( ParseObject obj : recipesList) {
                        final ParseObject object = obj;
                        ParseFile image = (ParseFile) obj.get("File");
                        image.getDataInBackground(new GetDataCallback() {
                            public void done(byte[] data, ParseException e) {
                                Log.d("picture",Integer.toString(data.length));
                                if (e == null) {

                                    bmp = BitmapFactory.decodeByteArray(data, 0, data.length);

                                    ImageView image4 = (ImageView) findViewById(R.id.alarmPic);

                                    // Set the Bitmap into the
                                    // ImageView
                                    image4.setImageBitmap(bmp);
                                    initializeData(object, bmp);
                                    Log.d("mytag", "prblem2");

                                } else {
                                    Log.d("mytag", "coldnt load picture");
                                }
                            }
                        });
                        initializeData(obj, bmp);
                    }
                } else {
                    Log.d("score", "Error: " + e.getMessage());
                }
                initializeAdapter();
                progressDialog.dismiss();
            }
        });
        count++;
    }if(!mWifi.isConnected() && count != 0) {//error on image
        Log.d("Invoke order","second if");
        ParseQuery<ParseObject> query = ParseQuery.getQuery("Collection");
        query.fromLocalDatastore();
        query.findInBackground(new FindCallback<ParseObject>() {

            @Override
            public void done(List<ParseObject> list, ParseException e) {
                if(e == null){
                    Log.d("score", "Retrieved " + list.size() + " recipes");
                    for(ParseObject obj : list){
                        final ParseObject object = obj;
                        ParseFile image = (ParseFile)obj.get("File");


                        image.getDataInBackground(new GetDataCallback() {
                            public void done(byte[] data, ParseException e) {
                                Log.d("picture",Integer.toString(data.length));
                                if (e == null) {


                                    bmp = BitmapFactory.decodeByteArray(data, 0, data.length);
                                    ImageView image22 = (ImageView) findViewById(R.id.alarmPic);

                                    // Set the Bitmap into the
                                    // ImageView
                                    image22.setImageBitmap(bmp);
                                    initializeData(object, bmp);
                                    Log.d("mytag", "prblem1");

                                } else {
                                    Log.d("mytag", "coldnt load picture");
                                }
                            }
                        });
                        initializeData(obj, bmp);
                    }
                }else {
                    Log.d("score", "Error: " + e.getMessage());
                }
                initializeAdapter();
            }
        });
    }


    setContentView(R.layout.activity_main);
    recyclerView = (RecyclerView)findViewById(R.id.recyclerView);
    manager = new LinearLayoutManager(getApplicationContext());
    recyclerView.setHasFixedSize(true);
    recyclerView.setLayoutManager(manager);

    //added to avoid no adapter set exception
    //recipes = new ArrayList<>();
    RVAdapter adapter = new RVAdapter(recipes);
    recyclerView.setAdapter(adapter);
    adapter.notifyDataSetChanged();
}
private void initializeAdapter(){
    RVAdapter adapter = new RVAdapter(recipes);
    recyclerView.setAdapter(adapter);
}
private void initializeData(ParseObject obj,Bitmap bmp){
    recipes.add(new Recipe(obj.getString("Description"), obj.getString("shortDescription"), obj.getString("Name"), bmp));
    Log.d("score", Integer.toString(recipes.size()));
}

}

Answer 1

您可以使用AsynkTask

class getBitmapFromURL extends AsyncTask<String, Void, Bitmap> {

    ParseFile img;

    public getBitmapFromURL(ParseFile img) {

        this.img = img;
    }

    protected Bitmap doInBackground(String... urls) {

        try {

            URL url = new URL(img.getUrl());
            HttpURLConnection connection = (HttpURLConnection) url
            .openConnection();
            connection.setDoInput(true);
            connection.connect();
            InputStream input = connection.getInputStream();

            return BitmapFactory.decodeStream(input);

        } catch (IOException e) {

        }

        return null;
    }

    protected void onPostExecute(final Bitmap bitmap) {

        if (bitmap != null) {

            image22.setImageBitmap(bitmap);
        }
    }
}

并像这样使用

ParseFile image = (ParseFile)obj.get("File");

new getBitmapFromURL(image).execute("");

在RecyclerView.Adapter的http://developer.android.com/training/material/lists-cards.html

的onBindViewHolder方法中执行此操作

@Override
public void onBindViewHolder(ViewHolder viewHolder, final int position) {

    viewHolder.image22.setImageBitmap(bitmap);
}

Answer 2

只需获取文件网址并将其放入毕加索。

String url = parseFile.getUrl();