android - 多个适配器更新列表项的通用 AsyncTask

Question

我是 Android 的新手，我有以下代码显示适配器中的项目列表。

我有四个不同的适配器，从那里我调用一个命令 AsyncTask 来更新结果。我已经实现了一个 Interface ApiResponse 并覆盖 apiResponseProcessing() 以获得结果。

在列表项中 “添加到购物车” 按钮已添加到每一行中。 OnClick 我向服务器请求的那个按钮。在该响应成功时，我想用“添加到购物车”更新按钮。

我有问题如何更新 onBindViewHolder() 中绑定(bind)的字符串。 我在该方法中取得了成功，但不知道如何通过该方法更新单击的按钮。

这是我的适配器

/**
 * Adapter
 **/

public class AlbumPhotoDetailAdapter
        extends RecyclerView.Adapter<AlbumPhotoDetailAdapter.ViewHolder> implements ApiResponse {

    private final ArrayList<Photo> mValues;
    Album album;
    private Activity mContext;
    private int mMemberId;

    public AlbumPhotoDetailAdapter(Activity context, ArrayList<Photo> items) {
        mValues = items;
        this.mContext = context;
        mMemberId = MemberPreference.getMemberId(mContext);
    }

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(parent.getContext())
                .inflate(R.layout.album_photo_detail_sub_view, parent, false);
        return new ViewHolder(view);
    }

    @Override
    public void onBindViewHolder(final ViewHolder holder, final int position) {
        final Photo photo = mValues.get(position);

        /**
         * Album Owner Name
         */
        String mOwnerName = photo.getOwnerName();
        String mOwnerProfilePic = photo.getOwnerImage();
        String mDateTime = photo.getDatetime();
        String mPrice = String.valueOf(photo.getPrice());

        /**
         * Price String
         */
        String priceStr = String.format(mContext.getString(R.string.string_dollar_price), mPrice);
        holder.mAlbumPhotoDetailPhotoPrice.setText(priceStr);

        /**
         * Main Image
         */
        Picasso.with(mContext).load(photo.getLink())
                .error(R.drawable.ic_place_holder_circle)
                .placeholder(R.drawable.ic_place_holder_circle)
                .transform(new ImageTransformation(holder.mAlbumPhotoDetailSubMainImage))
                .into(holder.mAlbumPhotoDetailSubMainImage);

        /**
         *  Owner Name and Profile Pic
         */
        holder.mAlbumPhotoDetailSubOwnerNameTextView.setText(mOwnerName);
        Picasso.with(mContext).load(mOwnerProfilePic)
                .error(R.drawable.ic_place_holder_circle)
                .placeholder(R.drawable.ic_place_holder_circle)
                .resize(100, 100)
                .transform(new CircleTransform())
                .into(holder.mAlbumPhotoDetailSubOwnerImage);

        mDateTime = mDateTime != null ? DateUtils.getNiceTime(mDateTime) : "----";
        holder.mAlbumPhotoDetailSubOwnerPostedTimeTextView.setText(mDateTime);       

        // Photo Add to cart.
        holder.mAddToCartButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if(InternetConnection.checkConnection(mContext)) {
                    new BackgroundAsyncTask(mContext, (ApiResponse) mContext, mMemberId, photo.getId()).execute();
                } else {
                    DailyStudio.noInternetConnectionToast(mContext);
                }
            }
        });
    }


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

    @Override
    public void apiResponseProcessing(String response) {
        Log.i(TAG,"Api Response : "+response);
        if(response.equals(Fields.JSON_SUCCESS)) {
        }
    }

    /**
     * View Holder
     */
    public static class ViewHolder extends RecyclerView.ViewHolder {

        public final View mView;

        private ImageView mAlbumPhotoDetailSubOwnerImage;
    private ImageView mAlbumPhotoDetailSubMainImage;
        private TextView mAlbumPhotoDetailSubOwnerNameTextView;
        private TextView mAlbumPhotoDetailSubOwnerPostedTimeTextView;     
        private TextView mAlbumPhotoDetailPhotoPrice;
        private TextView mAlbumPhotoDetailSubDescription;
        private Button mAddToCartButton;

        public ViewHolder(View view) {
            super(view);
            mView = view;

            mAlbumPhotoDetailSubOwnerImage = (ImageView) view.findViewById(R.id.album_photo_detail_sub_owner_image);
        mAlbumPhotoDetailSubMainImage = (ImageView) view.findViewById(R.id.album_photo_detail_sub_main_image);          
        mAlbumPhotoDetailSubOwnerNameTextView = (TextView) view.findViewById(R.id.album_photo_detail_sub_owner_name_text_view);
            mAlbumPhotoDetailSubOwnerPostedTimeTextView = (TextView) view.findViewById(R.id.album_photo_detail_sub_owner_posted_time_text_view);
            mAlbumPhotoDetailPhotoPrice = (TextView) view.findViewById(R.id.album_photo_detail_photo_price);
            mAlbumPhotoDetailSubDescription = (TextView) view.findViewById(R.id.album_photo_detail_sub_description);
            mAddToCartButton = (Button) view.findViewById(R.id.album_photo_detail_photo_add_to_cart_button);
        }
    }
}

这是我的界面

/**
* Interface..
*/

public interface ApiResponse {

    public void apiResponseProcessing(String response);

}

这是我的后台 AsyncTask

/**
* Background AsyncTask...
*/

public class BackgroundAsyncTask extends AsyncTask<Void, Void, String> {

    private Context context;
    private String accessToken;
    private int memberId;
    private int photoId;
    private ApiResponse objIBaseApi;

    public BackgroundAsyncTask(Context context, ApiResponse apiResponse, int memberId, int photoId) {
        this.context = context;
        this.memberId = memberId;
        this.photoId = photoId;
        accessToken = MemberPreference.getAccessToken(context);
        this.objIBaseApi = apiResponse;
    }

    @Override
    protected void onPreExecute() {
        super.onPreExecute();
    }

    @Override
    protected String doInBackground(Void... params) {

        JSONObject json = JSONParser.addToCartPhoto(accessToken, memberId, photoId);

        if(json != null) {
            Log.i(TAG,"First Json : "+json.toString());
            try {
                if (json.getString(Fields.RESULT).equalsIgnoreCase(Fields.JSON_SUCCESS)) {
                    return Fields.JSON_SUCCESS;
                } else if(json.getString(Fields.JSON_ERROR).equalsIgnoreCase(Fields.ERROR_ACCESS_DENIED)) {
                    String refreshToken = MemberPreference.getRefreshToken(context);

                    JSONObject newJSONObject = JSONParser.loginMemberWithRefreshToken(refreshToken, Integer.toString(memberId));

                    if(newJSONObject != null) {
                        if(newJSONObject.getString(Fields.JSON_ERROR).equalsIgnoreCase(Fields.ERROR_ACCESS_DENIED)) {
                            return Fields.ERROR_ACCESS_DENIED;
                        } else {
                            return Fields.JSON_SUCCESS;
                        }
                    } else
                        return Fields.ERROR_ACCESS_DENIED;

                } else {
                    return Fields.JSON_ERROR;
                }
            } catch (JSONException e) {
                e.printStackTrace();
                return Fields.JSON_ERROR;
            }
        }
        return Fields.JSON_ERROR;
    }

    @Override
    protected void onPostExecute(String result) {
        super.onPostExecute(result);

        objIBaseApi.apiResponseProcessing(result);

    }
}

是否有任何解决方案或更好的方法来做到这一点？

您的帮助将不胜感激。谢谢。

Answer 1

您可以在适配器中使用的 bean 类中保留一个标志 isAddedToCart 变量(照片)。现在只需在用户单击“添加到购物车”按钮后在您的异步任务中传递位置。获得成功后，您只需要从传递给适配器的 bean 列表中找到 bean，并将标志 isAddedToCart 更改为 true 并通知您的适配器即可。这是代码 fragment :-

摄影课

public class Photo{
private boolean isAddedToCart;

public void setAddedTOCart(boolean isAdded){
   isAddedToCart = isAdded;
}
public boolean isAddedToCart(){
   return isAddedToCart;
}

}

AlbumPhotoDetailAdapter onBindViewHolder

@Override
public void onBindViewHolder(final ViewHolder holder, final int position) {
    final Photo photo = mValues.get(position);

    /**
     * Album Owner Name
     */
    String mOwnerName = photo.getOwnerName();
    String mOwnerProfilePic = photo.getOwnerImage();
    String mDateTime = photo.getDatetime();
    String mPrice = String.valueOf(photo.getPrice());
    String isAdded = photo.isAddedToCart();

    /**
     * Price String
     */
    String priceStr = String.format(mContext.getString(R.string.string_dollar_price), mPrice);
    holder.mAlbumPhotoDetailPhotoPrice.setText(priceStr);

    /**
     * Main Image
     */
    Picasso.with(mContext).load(photo.getLink())
            .error(R.drawable.ic_place_holder_circle)
            .placeholder(R.drawable.ic_place_holder_circle)
            .transform(new ImageTransformation(holder.mAlbumPhotoDetailSubMainImage))
            .into(holder.mAlbumPhotoDetailSubMainImage);

    /**
     *  Owner Name and Profile Pic
     */
    holder.mAlbumPhotoDetailSubOwnerNameTextView.setText(mOwnerName);
    Picasso.with(mContext).load(mOwnerProfilePic)
            .error(R.drawable.ic_place_holder_circle)
            .placeholder(R.drawable.ic_place_holder_circle)
            .resize(100, 100)
            .transform(new CircleTransform())
            .into(holder.mAlbumPhotoDetailSubOwnerImage);

    mDateTime = mDateTime != null ? DateUtils.getNiceTime(mDateTime) : "----";
    holder.mAlbumPhotoDetailSubOwnerPostedTimeTextView.setText(mDateTime);       
if(isAdded){
   holder.mAddToCartButton.setText("Added TO Cart");
}else{
   holder.mAddToCartButton.setText("Add TO Cart");    
}
    // Photo Add to cart.
    holder.mAddToCartButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            if(InternetConnection.checkConnection(mContext)) {
                new BackgroundAsyncTask(mContext, (ApiResponse) mContext, mMemberId, photo.getId(),position).execute();
            } else {
                DailyStudio.noInternetConnectionToast(mContext);
            }
        }
    });
}

您的界面

public interface ApiResponse {
     public void apiResponseProcessing(String response,int position);
}

您的适配器 apiResponceProcessing()

@Override
public void apiResponseProcessing(String response,int position) {
    Log.i(TAG,"Api Response : "+response);
    if(response.equals(Fields.JSON_SUCCESS)) {
        mValues.get(position).setAddedTOCart(true);
        notifyDataSetChange();
    }
}

最后是你的BackgroundAsyncTask

public class BackgroundAsyncTask extends AsyncTask<Void, Void, String> {

private Context context;
private String accessToken;
private int memberId;
private int photoId; 
private int mPosition;
private ApiResponse objIBaseApi;

public BackgroundAsyncTask(Context context, ApiResponse apiResponse, int memberId, int photoId,int position) {
    this.context = context;
    this.memberId = memberId;
    this.photoId = photoId;
    accessToken = MemberPreference.getAccessToken(context);
    this.objIBaseApi = apiResponse;
    this.mPosition = position;
}

@Override
protected void onPreExecute() {
    super.onPreExecute();
}

@Override
protected String doInBackground(Void... params) {

    JSONObject json = JSONParser.addToCartPhoto(accessToken, memberId, photoId);

    if(json != null) {
        Log.i(TAG,"First Json : "+json.toString());
        try {
            if (json.getString(Fields.RESULT).equalsIgnoreCase(Fields.JSON_SUCCESS)) {
                return Fields.JSON_SUCCESS;
            } else if(json.getString(Fields.JSON_ERROR).equalsIgnoreCase(Fields.ERROR_ACCESS_DENIED)) {
                String refreshToken = MemberPreference.getRefreshToken(context);

                JSONObject newJSONObject = JSONParser.loginMemberWithRefreshToken(refreshToken, Integer.toString(memberId));

                if(newJSONObject != null) {
                    if(newJSONObject.getString(Fields.JSON_ERROR).equalsIgnoreCase(Fields.ERROR_ACCESS_DENIED)) {
                        return Fields.ERROR_ACCESS_DENIED;
                    } else {
                        return Fields.JSON_SUCCESS;
                    }
                } else
                    return Fields.ERROR_ACCESS_DENIED;

            } else {
                return Fields.JSON_ERROR;
            }
        } catch (JSONException e) {
            e.printStackTrace();
            return Fields.JSON_ERROR;
        }
    }
    return Fields.JSON_ERROR;
}

@Override
protected void onPostExecute(String result) {
    super.onPostExecute(result);

    objIBaseApi.apiResponseProcessing(result,mPosition);

}