解析JSON并提取条件项 [英] Parsing a JSON and extracting items with condition

问题描述

我的问题与此

My question is similar to this Implementing Search Filter in Adapter Class which parses a json array (without using pojo) but I would like to try to struggle the problem differently. I have a list of elements that must be filtered based on a condition and once this condition is verified, I want to retrieve the elements that verify it from the json array. In this example, I filtered the elements based on their name, and in the setContentValue () I would set the code and the hex string taking only those elements that have that name, otherwise during filtering the name has a different index from the code and the hex strings. How could I do that?

片段

public class ColorViewFragment extends Fragment {

private RecyclerView recyclerView;
private JSONArray json;
private ColorListAdapter adapter;

private EditText editColor;

@Nullable @Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {

    View view = inflater.inflate(R.layout.color_list, container, false);
    this.recyclerView = view.findViewById(R.id.recyclerView);

    /*
    try {
        this.recyclerView.setAdapter(new ColorListAdapter(this.json));
    } catch (JSONException e) {
        e.printStackTrace();
    }
    */

    try {
        adapter = new ColorListAdapter(json);
    } catch (JSONException e) {
        e.printStackTrace();
    }
    recyclerView.setAdapter(adapter);


    RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(getActivity());
    this.recyclerView.setLayoutManager(layoutManager);

    //
    editColor = view.findViewById(R.id.editText);
    editColor.addTextChangedListener(new TextWatcher() {

        @Override
        public void beforeTextChanged(CharSequence s, int start, int count, int after) {

        }

        @Override
        public void onTextChanged(CharSequence s, int start, int before, int count) {

            ColorViewFragment.this.adapter.getFilter().filter(s);

        }

        @Override
        public void afterTextChanged(Editable s) {

        }
    });

    return view;
}

public void setJSON(JSONArray newJson){
    this.json = newJson;
}

适配器

public class ColorListAdapter extends RecyclerView.Adapter implements Filterable {

private JSONArray colorList;

private List<String> colorListFiltered = new ArrayList<String>();

public ColorListAdapter(JSONArray json) throws JSONException {
    super();
    if (json != null) {
        this.colorList = json;

            for (int i=0;i<json.length();i++){
                //colorListFiltered.add((colorList.getString(i)));
                colorListFiltered.add(json.getJSONObject(i).getString("Name"));
            }
    }
}


@Override
public Filter getFilter() {
    return new colorFilter();
}


@NonNull
@Override
public RecyclerView.ViewHolder onCreateViewHolder(@NonNull ViewGroup viewGroup, int i) {
    View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.fragment_color_view, viewGroup, false);
    return new ColorListHolder(view);
}

@Override
public void onBindViewHolder(@NonNull RecyclerView.ViewHolder viewHolder, int i) {
    try {
        ((ColorListHolder) viewHolder).setContentValue(i);
    } catch (JSONException e) {
        e.printStackTrace();
    }
}

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

private class ColorListHolder extends RecyclerView.ViewHolder {

    private TextView colorCodeText;
    private TextView colorNameText;
    private CardView imageView;

    public ColorListHolder(@NonNull View itemView) {
        super(itemView);
        this.colorCodeText = itemView.findViewById(R.id.colorCode_text);
        this.colorNameText = itemView.findViewById(R.id.colorName_text);
        this.imageView = itemView.findViewById(R.id.colorView);
    }

    public void setContentValue(int index) throws JSONException {

        this.colorNameText.setText(colorListFiltered.get(index));
        //this.colorNameText.setText(((JSONObject) colorList.get(index)).getString("Name"));
        this.colorCodeText.setText(((JSONObject) colorList.get(index)).getString("ColorCode"));
        this.imageView.setCardBackgroundColor(Color.parseColor(((JSONObject) colorList.get(index)).getString("HexString")));

    }
}


public class colorFilter extends Filter{

    @Override
    protected FilterResults performFiltering(CharSequence constraint) {

        FilterResults Result = new FilterResults();
        // if constraint is empty return the original names

        if(constraint.length() == 0 ) {
            ArrayList<String> arrColorList = new ArrayList<>();
            for (int i = 0; i < colorList.length(); i++) {
                try {
                    arrColorList.add(colorList.getJSONObject(i).getString("Name"));
                } catch (JSONException e) {
                    e.printStackTrace();
                }
            }
            Result.values = arrColorList;
            Result.count = arrColorList.size();
            return Result;
        }

        /*if(constraint.length() == 0 ){
            Result.values = colorList;
            Result.count = colorList.length();
            return Result;*/

        else {

            List<String> Filtered_Names = new ArrayList<String>();
            String filterString = constraint.toString().toLowerCase();
            String filterableString = "";

            for (int i = 0; i < colorList.length(); i++) {
                try {
                    filterableString = (colorList.getJSONObject(i)).getString("Name");
                } catch (JSONException e) {
                    e.printStackTrace();
                }

                if (filterableString.toLowerCase().contains(filterString)) {
                    Filtered_Names.add(filterableString);
                }
            }

            Result.values = Filtered_Names;
            Result.count = Filtered_Names.size();
            return Result;

        }

    }

    @Override
    protected void publishResults(CharSequence constraint, FilterResults results) {

        colorListFiltered = (ArrayList<String>) results.values;
        notifyDataSetChanged();
    }
}

推荐答案

您将colorListFiltered用于名称，但将colorList用于setContentValue中的十六进制代码.前两个列表相同，但是当您过滤colorListFiltered时，它们将变得不同.

You use colorListFiltered for names but you use colorList for hex codes in setContentValue. First two lists are same but when you filter colorListFiltered they are getting different.

更改此内容

 private JSONArray colorList;

 private List<String> colorListFiltered = new ArrayList<String>();

到

private List<JSONObject> colorList = new ArrayList<JSONObject>();

private List<JSONObject> colorListFiltered = new ArrayList<JSONObject>();

和您的performFiltering

List<JSONObject> Filtered_Names = new ArrayList<JSONObject>();
                String filterString = constraint.toString().toLowerCase();
                String filterableString = "";

                for (int i = 0; i < colorList.size(); i++) {
                    try {
                        filterableString = (colorList.get(i)).getString("Name");
                    } catch (JSONException e) {
                        e.printStackTrace();
                    }

                    if (filterableString.toLowerCase().contains(filterString)) {
                        Filtered_Names.add(colorList.get(i));
                    }
                }

setContentValue:

公共无效setContentValue(int索引)抛出JSONException {

public void setContentValue(int index) throws JSONException {

this.colorNameText.setText(colorListFiltered.get(index).getString("Name"));
this.colorCodeText.setText(colorListFiltered.get(index).getString("ColorCode"));
this.imageView.setCardBackgroundColor(Color.parseColor(colorListFiltered.get(index).getString("HexString"));

}

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