Android 實現列表搜索

RecycleView搜索過濾器-getFilter()
記錄一下，最近做項目，有一個需求，在列表中需要監聽輸入數據來過濾列表


Android 提供了Fileterable類，可以通過過濾器來過濾數據。通常，getFilter()方法必須在提供過濾條件的適配器類中被重寫，以通過列表進行搜索。下面是通過getFilter()，來過濾數據。

完整Adapter代碼：

public class BuildingAdapter extends RecyclerView.Adapter<BuildingAdapter.BuildingHolder> implements Filterable {
    private List<String> mSourceList = new ArrayList<>();
    private List<String> mFilterList = new ArrayList<>();
    private Context mContext;
    private OnItemClickListener mListener;

    public BuildingAdapter(Context context, List<String> list) {
        this.mContext = context;
        this.mSourceList = list;
        //這裏需要初始化filterList
        mFilterList = list;
    }

    public void setListener(OnItemClickListener listener) {
        this.mListener = listener;
    }

    @NonNull
    @Override
    public BuildingHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        return new BuildingHolder(LayoutInflater.from(mContext).inflate(R.layout.item_building, parent, false));
    }

    @Override
    public void onBindViewHolder(BuildingHolder holder, int position) {
        holder.tvType.setText(mContext.getString(R.string.building));
        holder.tvType.setBackgroundResource(R.drawable.bg_building);
        //這裏也是過濾後的list
        holder.tvName.setText(mFilterList.get(position));
    }

    @Override
    public int getItemCount() {
        //注意這裏需要是過濾後的list
        return mFilterList.size();
    }

    @Override
    public Filter getFilter() {
        return new Filter() {
            @Override
            protected FilterResults performFiltering(CharSequence charSequence) {
                String filter = charSequence.toString();
                if (TextUtils.isEmpty(filter)) {
                    //沒有過濾的內容，則使用源數據
                    mFilterList = mSourceList;
                } else {
                    filter = filter.toUpperCase();//小寫變大寫，是大寫的不變
                    List<String> filteredList = new ArrayList<>();
                    for (String str : mSourceList) {
                        //這裏根據需求，添加匹配規則
                        if (str.contains(filter)) {
                            filteredList.add(str);
                        }
                    }
                    mFilterList = filteredList;
                }
                FilterResults filterResults = new FilterResults();
                filterResults.values = mFilterList;
                return filterResults;
            }

            @Override
            protected void publishResults(CharSequence charSequence, FilterResults filterResults) {
                mFilterList = (ArrayList<String>) filterResults.values;
                notifyDataSetChanged();
            }
        };
    }

    class BuildingHolder extends RecyclerView.ViewHolder {
        TextView tvType, tvName;

        public BuildingHolder(@NonNull View itemView) {
            super(itemView);
            tvType = itemView.findViewById(R.id.tv_type);
            tvName = itemView.findViewById(R.id.tv_name);
            itemView.setOnClickListener(view -> {
                if (mListener != null) {
                    mListener.onItemClick(getAdapterPosition());
                }
            });
        }
    }

    public interface OnItemClickListener {
        void onItemClick(int position);
    }
}

設置EditText監聽,並監聽軟鍵盤搜索按鈕

etSearch.addTextChangedListener(new TextWatcher() {
            @Override
            public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {

            }

            @Override
            public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
                mAdapter.getFilter().filter(charSequence.toString());
            }

            @Override
            public void afterTextChanged(Editable editable) {

            }
        });
        
        etSearch.setOnEditorActionListener((textView, actionId, event) -> {
            if (actionId == EditorInfo.IME_ACTION_SEARCH) {
                hideInput();
                mAdapter.getFilter().filter(etSearch.getText().toString());
                return true;
            }
            return false;
        });

結束！