Question

主要活动.java

spring xml

ProductAdapter.java

ProgressDialog pd;
    public static final String ROOT_URL="http://www.tontosworld.com/ws/";
    public static final String PODAY_URL="poday-json.php";
    public static final String PRODUCTS_DOODLES_URL="products-doodles-json.php";
    public static final String PRODUCTS_GREETING_CARDS_URL="products-greetingcards-json.php";
    public static final String PRODUCTS_HANDICRAFTS_URL="products-handicrafts-json.php";
    public static final String PRODUCTS_MODERNART_URL="products-modernart-json.php";
    public static final String PRODUCTS_OTHERS_URL="products-others-json.php";
    public static final String PRODUCTS_PAINTINGS_URL="products-paintings-json.php";
    public static final String PRODUCTS_PHOTOGRAPHS_URL="products-photographs-json.php";
    public static final String PRODUCTS_POSTERS_URL="products-posters-json.php";
    public static final String PRODUCTS_SKETCHES_URL="products-sketches-json.php";
    public static final String PODAY_ID="products.id";
    public static final String PODAY_PRIMARY_IMAGE="products.p_img";
    public static final String PODAY_PNAME="products.p_name";
    public static final String PODAY_PRICE="products.price";
    public static final String PODAY_OFFPRICE="products.off_price";
    public static final String JSON_ARRAY="result";
    public static final String PRODUCT_ID="id";
    public static final String PRODUCT_NAME="p_name";
    public static final String PRODUCT_DESC="desc";
    public static final String PRODUCT_ARTIST_ID="artist_id";
    public static final String PRODUCT_PRICE="price";
    public static final String PRODUCT_CATEGORY="category";
    public static final String PRODUCT_CITY1="city1";
    public static final String PRODUCT_CITY2="city2";
    public static final String PRODUCT_IMG="p_img";
    public static final String PRODUCT_S1_IMG="s1_img";
    public static final String PRODUCT_S2_IMG="s2_img";
    public JSONArray _poday,_doodles,_greetingCards,_handicrafts,_modernArt,_others,_paintings,_photographs,_posters,_sketches;
    String poday,doodles,greetingCards,handicrafts,modernArt,others,paintings,photographs,posters,sketches;
    ArrayList<String> parsedPODAY_ID=new ArrayList<>();
    ArrayList<String> parsedPODAY_P_IMG=new ArrayList<>();
    ArrayList<String> parsedPODAY_NAME=new ArrayList<>();
    ArrayList<String> parsedPODAY_PRICE=new ArrayList<>();
    ArrayList<String> parsedPODAY_OFFPRICE=new ArrayList<>();

    int i;
    Bitmap bitmap;
    RecyclerView rvPoday;
    ProductAdapter adapter;

@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.app_bar);
        setSupportActionBar(toolbar);
        getSupportActionBar().setDisplayShowHomeEnabled(true);
        NavigationDrawerFragment drawerFragment=(NavigationDrawerFragment)getSupportFragmentManager().findFragmentById(R.id.fragment_navigation_drawer);
        drawerFragment.setUp(R.id.fragment_navigation_drawer, (DrawerLayout) findViewById(R.id.drawer_layout), toolbar);

        pd=ProgressDialog.show(MainActivity.this, "Please Wait...", null, true, true);
        callPoday(PODAY_URL);

}

    public List<Product> getDataPoday(){
        List<Product> data=new ArrayList<>();
        for(i=0;i<parsedPODAY_ID.size();i++){
            Product current=new Product();
            current.productName=parsedPODAY_NAME.get(i);
            current.price=parsedPODAY_OFFPRICE.get(i);
            current.pImage=getImage("http://www.tontosworld.com/img/productimages/" + parsedPODAY_P_IMG.get(i));
            data.add(current);
        }
        return data;

    }

    public Bitmap getImage(String s) {
        LoadImageTask task=new LoadImageTask();
        task.execute(s);
        return bitmap;
    }

private void callPoday(String podayUrl) {
        CallJsonPodayTask task=new CallJsonPodayTask();
        task.execute(ROOT_URL + "" + podayUrl);
    }

    class LoadImageTask extends AsyncTask<String,String,Bitmap>{

        @Override
        protected Bitmap doInBackground(String... strings) {
            try {
                bitmap= BitmapFactory.decodeStream((InputStream) new URL(strings[0]).getContent());
            } catch (IOException e) {
                e.printStackTrace();
            }
            return bitmap;
        }

        @Override
        protected void onPostExecute(Bitmap bitmap) {
            super.onPostExecute(bitmap);
            if(bitmap==null){
                Toast.makeText(MainActivity.this,"Error in loading image",Toast.LENGTH_LONG).show();
            }
        }
    }

 class CallJsonPodayTask extends AsyncTask<String,Void,String>{

        @Override
        protected String doInBackground(String... strings) {
            String uri = strings[0];

            BufferedReader bufferedReader = null;
            try {
                URL url = new URL(uri);
                HttpURLConnection con = (HttpURLConnection) url.openConnection();
                StringBuilder sb = new StringBuilder();

                bufferedReader = new BufferedReader(new InputStreamReader(con.getInputStream()));

                String json;
                while ((json = bufferedReader.readLine()) != null) {
                    sb.append(json + "\n");
                }

                return sb.toString().trim();

            } catch (Exception e) {
                return null;
            }
        }

@Override
        protected void onPostExecute(String s) {
            super.onPostExecute(s);
            poday=s;
            parsePoday(poday);

        }
    }

    private void parsePoday(String poday) {

        _poday=null;
        try {
            JSONObject jsonObject = new JSONObject(poday);
            _poday = jsonObject.getJSONArray(JSON_ARRAY);
        } catch (JSONException e) {
            e.printStackTrace();
        }
        try {
            for (int i = 0; i < _poday.length(); i++) {
                JSONObject jj = _poday.getJSONObject(i);
                parsedPODAY_ID.add(jj.getString(PODAY_ID));
                parsedPODAY_NAME.add(jj.getString(PODAY_PNAME));
                parsedPODAY_P_IMG.add(jj.getString(PODAY_PRIMARY_IMAGE));
                parsedPODAY_PRICE.add(jj.getString(PODAY_PRICE));
                parsedPODAY_OFFPRICE.add(jj.getString(PODAY_OFFPRICE));
                //Toast.makeText(this, "ID:" + parsedPODAY_ID.get(i) + "\nNAME:" + parsedPODAY_NAME.get(i) + "\nPIMG:" + parsedPODAY_P_IMG.get(i) + "\nPRICE" + parsedPODAY_PRICE.get(i) + "\nOFFPRICE" + parsedPODAY_OFFPRICE.get(i), Toast.LENGTH_LONG).show();
            }
        }
        catch (JSONException e) {
            e.printStackTrace();
            Toast.makeText(this,"Error",Toast.LENGTH_LONG).show();
        }
        finally {

            rvPoday=(RecyclerView)findViewById(R.id.rvProductOfTheDay);
            adapter=new ProductAdapter(MainActivity.this,getDataPoday());
            Toast.makeText(this,""+adapter.getItemCount(),Toast.LENGTH_LONG).show();
            rvPoday.setAdapter(adapter);
            LinearLayoutManager llm=new LinearLayoutManager(MainActivity.this);
            llm.setOrientation(LinearLayoutManager.HORIZONTAL);
            rvPoday.setLayoutManager(llm);
        }
    }

recycler_view_single.xml

public class ProductAdapter extends RecyclerView.Adapter<ProductAdapter.MyViewHolder> {
    public LayoutInflater inflater;
    List<Product> data= Collections.emptyList();

    public ProductAdapter(Context context,List<Product> data){
        inflater=LayoutInflater.from(context);
        this.data=data;
    }

    @Override
    public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View v=inflater.inflate(R.layout.recycler_view_single,parent,false);
        MyViewHolder holder=new MyViewHolder(v);
        return holder;
    }

    @Override
    public void onBindViewHolder(MyViewHolder holder, int position) {
        Product current=data.get(position);
        holder.name.setText(current.productName);
        holder.price.setText(current.price);
        holder.image.setImageBitmap(current.pImage);
    }

    @Override
    public int getItemCount() {
        return data.size();
    }

    class MyViewHolder extends RecyclerView.ViewHolder{

        TextView name,price;
        ImageView image;

        public MyViewHolder(View itemView) {
            super(itemView);
            name=(TextView)itemView.findViewById(R.id.rvItemName);
            price=(TextView)itemView.findViewById(R.id.rvItemPrice);
            image=(ImageView)itemView.findViewById(R.id.rvItemImage);
        }
    }
}


Product.java

public class Product {
    String productName,price;
    Bitmap pImage;
}

activity_main.xml中

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:orientation="vertical">

<android.support.v7.widget.CardView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_gravity="center"
    android:background="?android:selectableItemBackground">

    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:gravity="center"
        android:orientation="vertical">

        <ImageView
            android:id="@+id/rvItemImage"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:src="@mipmap/ic_launcher" />

        <TextView
            android:id="@+id/rvItemName"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Name" />

        <TextView
            android:id="@+id/rvItemPrice"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Price" />

    </LinearLayout>
</android.support.v7.widget.CardView>

</LinearLayout>

我从json调用了数据，在解析数据之后我附加了回收器视图。但它没有显示回收器视图。

我在最后一个parsePoday（）方法块中附加了回收站视图

Answer 1

您将recycleviewview放在您的activity_main.xml中的scrollview中，因此请从scrollview中取出recyclerview，或者只是删除scrollview并再试一次

Answer 2

parsePoday()方法仅在AsyncTask完成时调用，因此当AsyncTask运行时，RecyclerView仍然没有连接适配器。

没有显示回收器视图。即使我已经连接了适配器，也会出现“没有连接适配器，跳过布局”的错误

2 个答案: