Question

我有一个铃声的列表视图..我通过mysql数据库提供列表..（如歌曲名称，歌曲网址...）。我通过在我的数据库中添加新项目在我的列表视图中动态添加产品（铃声），因此除了行图标外，这些数据都不在我的应用程序内。

这是视图

正如您所看到的，我有一个书签边框图标，当用户点击它时，它会变成选定的...这就是它的工作原理：

    @Override
    public void favOnClick(int position) {
       Product product = productList.get(position);
        if (product.faved) {
            sharedPreference.addFavorite(activity,product);
            product.setFavId(R.mipmap.bookmarked);
            product.faved=false;
        }else {
            sharedPreference.removeFavorite(activity,product);
            product.setFavId(R.mipmap.bookmark_border);
            product.faved = true;
        }
        adapter.notifyDataSetChanged();  
        };

但在我的＆＃34; FAVORITES＆＃34;中不会发生任何事情。选项卡..即使选中它时书签图标的状态也不会被保存..

自定义适配器

    public class FunDapter<T> extends BaseAdapter {

       public interface PlayPauseClick {
             void favOnClick(int position);
            }


       private PlayPauseClick callback;
       public void setPlayPauseClickListener(PlayPauseClick listener) {
            this.callback = listener;
        }


    protected List<T> mDataItems;
    protected List<T> mOrigDataItems;
    protected final Context mContext;
    private final int mLayoutResource;
    private final BindDictionary<T> mBindDictionary;



    public FunDapter(Context context, List<T> dataItems, int layoutResource,
                     BindDictionary<T> dictionary) {
      this(context, dataItems, layoutResource, null, dictionary);
    }


    public FunDapter(Context context, List<T> dataItems, int layoutResource,
                     LongExtractor<T> idExtractor, BindDictionary<T> dictionary) {
        this.mContext = context;
        this.mDataItems = dataItems;
        this.mOrigDataItems = dataItems;
        this.mLayoutResource = layoutResource;
        this.mBindDictionary = dictionary;
        sharedPreference = new SharedPreference();
    }



    public void updateData(List<T> dataItems) {
        this.mDataItems = dataItems;
        this.mOrigDataItems = dataItems;
        notifyDataSetChanged();
    }

    @Override
    public int getCount() {
        if (mDataItems == null || mBindDictionary == null) return 0;

        return mDataItems.size();
    }

    @Override
    public T getItem(int position) {
        return mDataItems.get(position);
    }

    @Override
    public long getItemId(int position) {
        if(idExtractor == null) return position;
        else return idExtractor.getLongValue(getItem(position), position);
    }

    @Override
    public View getView(final int position, View convertView, ViewGroup parent) {

        View v = convertView;
        final GenericViewHolder holder;
        if (null == v) {
            LayoutInflater vi =
                    (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            v = vi.inflate(mLayoutResource, null);
            holder = new GenericViewHolder();
            holder.root = v;


            //init the sub views and put them in a holder instance
            FunDapterUtils.initViews(v, holder, mBindDictionary);
            v.setTag(holder);
            }else {
            holder = (GenericViewHolder) v.getTag();
            }

        final T item = getItem(position);
        showData(item, holder, position);

        Product product = (Product) mDataItems.get(position);
        holder.favImage=(ImageView)v.findViewById(R.id.favImage); 
        holder.favImage.setImageResource(product.getFavId());
        holder.favImage.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                if (callback != null) {
                      callback.favOnClick(position);
                    } 
            }
        }); 


        return v;
    }

}

产品型号类

    @SuppressWarnings("serial")
public class Product implements Serializable {
    @SerializedName("pid")
    public int pid;

    @SerializedName("name")
    public String name;

    @SerializedName("qty")
    public int qty;

    @SerializedName("price")
    public String description;

    @SerializedName("song_url")
    public String song_url;

    @SerializedName("date")
    public String date;


    public boolean paused = true;
    public boolean faved = true;

     private int favId;
    public int getFavId() {
        return favId;}
    public void setFavId(int favId) {
        this.favId = favId;} 
}

SharedPreferences类

   public class SharedPreference {

    public static final String PREFS_NAME = "PRODUCT_APP";
    public static final String FAVORITES = "Product_Favorite";

    public SharedPreference() {
        super();
    }

    // This four methods are used for maintaining favorites.
    public void saveFavorites(Context context, List<Product> favorites) {
        SharedPreferences settings;
        Editor editor;
        settings = context.getSharedPreferences(PREFS_NAME,Context.MODE_PRIVATE);
        editor = settings.edit();
        Gson gson = new Gson();
        String jsonFavorites = gson.toJson(favorites);
        editor.putString(FAVORITES, jsonFavorites);
        editor.commit();
    }

    public void addFavorite(Context context, Product product) {
        List<Product> favorites = getFavorites(context);
        if (favorites == null)
            favorites = new ArrayList<Product>();
            favorites.add(product);
            saveFavorites(context, favorites);
    }

    public void removeFavorite(Context context, Product product) {
        ArrayList<Product> favorites = getFavorites(context);
        if (favorites != null) {
            favorites.remove(product);
            saveFavorites(context, favorites);
        }
    }

    public ArrayList<Product> getFavorites(Context context) {
        SharedPreferences settings;
        List<Product> favorites;
        settings = context.getSharedPreferences(PREFS_NAME,Context.MODE_PRIVATE);
        if (settings.contains(FAVORITES)) {
            String jsonFavorites = settings.getString(FAVORITES, null);
            Gson gson = new Gson();
            Product[] favoriteItems = gson.fromJson(jsonFavorites,Product[].class);
            favorites = Arrays.asList(favoriteItems);
            favorites = new ArrayList<Product>(favorites);
        } else
            return null;

        return (ArrayList<Product>) favorites;
    }
}

我被困在这里几天了，你能帮助我吗？

这是我的项目链接，如果您想查看更多信息

~~http://symphonyrecords.ir/RingtoneApp.rar~~

Answer 1

此处存在两个问题（基于您的项目）

首先（保存书签Imageview的状态）

在适配器中创建一个方法，检查SharedPreferences中是否存在特定产品

    public boolean checkFavoriteItem(Product checkProduct) {
    boolean check = false;
    List<Product> favorites = sharedPreference.getFavorites(null, mContext);
    if (favorites != null) {
        for (Product product : favorites) {
            if (product.equals(checkProduct)) {
                check = true;
                break;
            }
        }
    }
    return check;
}

内部适配器检查共享偏好设置中是否存在产品，然后设置已添加书签可绘制并设置标记

if (checkFavoriteItem(product)) {
        holder.favoriteImg.setImageResource(R.mipmap.bookmarked);
        holder.favoriteImg.setTag("bookmarked");
    } else {
        holder.favoriteImg.setImageResource(R.mipmap.bookmark_border);
        holder.favoriteImg.setTag("bookmark_border");
    }

然后在favOnClick回调方法中

    @Override
    public boolean favOnClick(int position ,View v) {
        Product product = (Product) productList.get(position);
        ImageView button = (ImageView) v.findViewById(R.id.favImage);
        String tag = button.getTag().toString();
        if (tag.equalsIgnoreCase("bookmark_border")) {
            sharedPreference.addFavorite(activity,product);
            Toast.makeText(activity,"Added to Favorites",Toast.LENGTH_SHORT).show();
            button.setTag("bookmarked");
            button.setImageResource(R.mipmap.bookmarked);
        } else {
            sharedPreference.removeFavorite(activity,product);
            button.setTag("bookmark_border");
            button.setImageResource(R.mipmap.bookmark_border);
            Toast.makeText(activity,"Removed from Favorites",Toast.LENGTH_SHORT).show();
        }
        return true;
        }

第二次 （获取最喜欢的产品并将其传递给“FAVORITE”片段）

在getFavorite方法内添加一个String参数然后在您的“FAVORITE”片段中使用processFinish（您的AsyncResponse）调用您的getFavorite以获取您最喜欢的产品列表，然后设置您的适配器：

Context mContext;
`mContext = getContext();`

@Override
public void  processFinish(String s) {
    productList = sharedPreference.getFavorites(s, mContext);

    BindDictionary<Product> dict = new BindDictionary<Product>();
    dict.addStringField(R.id.tvName, new StringExtractor<Product>() {
        @Override
        public String getStringValue(Product product, int position) {
            return product.name;
        }
    });


    dict.addStringField(R.id.tvDescription, new StringExtractor<Product>() {
        @Override
        public String getStringValue(Product product, int position) {
            return product.description;

        }
    });


    dict.addStringField(R.id.tvQty, new StringExtractor<Product>() {
        @Override
        public String getStringValue(Product product, int position) {
            return "" + product.qty;

        }
    });


    adapter = new FunDapter<>(getActivity(), productList, R.layout.d_layout_list_d, dict);
    lvProduct.setAdapter(adapter);

}

Answer 2

确保favOnClick方法更改FunDapter.mDataItems中的对象。所以，更改回调方法：

    @Override
    public void favOnClick(int position) {
       Product product = adapter.get(position);
        if (product.faved) {
            sharedPreference.addFavorite(activity, product);
            product.setFavId(R.mipmap.bookmarked);
            product.faved=false;
        }else {
            sharedPreference.removeFavorite(activity, product);
            product.setFavId(R.mipmap.bookmark_border);
            product.faved = true;
        }
        adapter.notifyDataSetChanged();  
        };

Answer 3

检查一下，99% 的工作代码

<块引用>

点击收藏夹

List< RvModel > favorites_list = storageFavorites.loadFavourite();
            boolean exist = false;
            if (favorites_list == null) {
                favorites_list = new ArrayList<>();
            }
            for (int i = 0; i < favorites_list.size(); i++) {
                if (favorites_list.get(i).getId().equals(rvModelArrayList.get(position).getId())) {
                    exist = true;
                }
            }
            if (!exist) {
                ArrayList< RvModel > audios = new ArrayList< RvModel >(favorites_list);
                audios.add(rvModelArrayList.get(position));
                storageFavorites.storeImage(audios);
                holder.bookMarkBtn.setImageDrawable(activity.getResources().getDrawable(R.drawable.ic_bookmark_full));
            } else {
                ArrayList< RvModel > new_favorites = new ArrayList< RvModel >();
                for (int i = 0; i < favorites_list.size(); i++) {
                    if (!favorites_list.get(i).getId().equals(rvModelArrayList.get(position).getId())) {
                        new_favorites.add(favorites_list.get(i));

                    }
                }
                if (favorites) {
                    Log.v("DOWNLOADED", "favorites==true");
                    rvModelArrayList.remove(position);
                    notifyDataSetChanged();
                    //holder.ripple_view_wallpaper_item.setVisibility(View.GONE);
                }
                storageFavorites.storeImage(new_favorites);
                holder.bookMarkBtn.setImageDrawable(activity.getResources().getDrawable(R.drawable.ic_bookmark));
            }
        }

使用共享偏好创建收藏列表视图

3 个答案: