Question

我对Android编程比较陌生。我有一个RecycleView，CardView在其中排成行。单击任何行将打开与该行关联的新活动。在我将过滤器功能添加到此列表之前，一切都很顺利。当我搜索列表然后单击一个项目时，它不会打开与过滤结果相关联的活动。它会打开与原始列表中该位置的项目相关的活动。

示例 - 原始列表：AA，BA，CC，DA，ED，FF

搜索：＆＃39; A＆＃39;过滤结果：AA，BA，DA

但是当我点击项目DA时，它会打开CC的活动。我在适配器上调用了notifyDataSetChanged()。

我搜索并发现了类似的问题，但无法在我的代码中实现。

以下是代码：

     public class MainActivity extends AppCompatActivity implements ExampleAdapter.OnItemClickListener{
     public static final String EXTRA_IMG = "imageresource";
     public static final String EXTRA_TXT1 = "text1";
     public static final String EXTRA_TXT2 = "text2";
     public static final String EXTRA_TXT3 = "text3";

     private ArrayList<ExampleItem> mExampleList;
     private RecyclerView mRecyclerView;
     private ExampleAdapter mAdapter;
     private RecyclerView.LayoutManager mLayoutManager;


     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);

         createExampleList();
         buildRecyclerView();

         EditText editText = findViewById(R.id.editText);
         editText.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) {

             }

             @Override
             public void afterTextChanged(Editable s) {
                 filter(s.toString());
            }
         });

     }

     private void filter(String text) {
         ArrayList<ExampleItem> filteredList = new ArrayList<>();

         for (ExampleItem item : mExampleList) {
             if (item.getText1().toLowerCase().contains(text.toLowerCase())) {
                 filteredList.add(item);
             }
         }
         mAdapter.filterList(filteredList);
     }

     private void createExampleList() {
        //just creating list
     }

     private void buildRecyclerView() {
         mRecyclerView = findViewById(R.id.recyclerView);
         mRecyclerView.setHasFixedSize(true);
         mLayoutManager = new LinearLayoutManager(this);
         mAdapter = new ExampleAdapter(mExampleList);
         mRecyclerView.setLayoutManager(mLayoutManager);
         mRecyclerView.setAdapter(mAdapter);
         mAdapter.setOnItemClickListener(MainActivity.this);
     }

     @Override
     public void onItemClick(int position) {
         Intent detailintent = new Intent(this,DetailActivity.class);
         ExampleItem clickedItem = mExampleList.get(position);
         detailintent.putExtra(EXTRA_IMG,clickedItem.getImageResource());
         detailintent.putExtra(EXTRA_TXT1,clickedItem.getText1());
         detailintent.putExtra(EXTRA_TXT2,clickedItem.getText2());
         detailintent.putExtra(EXTRA_TXT3,clickedItem.getText3());
         startActivity(detailintent);
     }
     }

     public class ExampleAdapter extends RecyclerView.Adapter<ExampleAdapter.ExampleViewHolder> {
     private ArrayList<ExampleItem> mExampleList;
     private OnItemClickListener mListener;
     public interface OnItemClickListener{
         void onItemClick(int position);
     }
     public void setOnItemClickListener(OnItemClickListener listener){
         mListener=listener;
     }

     public class ExampleViewHolder extends RecyclerView.ViewHolder {
         public ImageView mImageView;
         public TextView mTextView1;
         public TextView mTextView2;
         public TextView mTextView3;

         public ExampleViewHolder(View itemView) {
             super(itemView);
             mImageView = itemView.findViewById(R.id.imageView);
             mTextView1 = itemView.findViewById(R.id.textView);
             mTextView2 = itemView.findViewById(R.id.textView7);
             mTextView3 = itemView.findViewById(R.id.textView2);
            itemView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    if(mListener != null ){
                        int position = getAdapterPosition();
                        if(position != RecyclerView.NO_POSITION){
                            mListener.onItemClick(position);
                        }
                    }
                }
            });
         }
     }

     public ExampleAdapter(ArrayList<ExampleItem> exampleList) {
         mExampleList = exampleList;
     }

     @Override
     public ExampleViewHolder onCreateViewHolder(ViewGroup parent, int viewType){
         View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.example_item,
            parent, false);
         ExampleViewHolder evh = new ExampleViewHolder(v);
         return evh;
     }

     @Override
     public void onBindViewHolder(ExampleViewHolder holder, int position) {
         ExampleItem currentItem = mExampleList.get(position);

         holder.mImageView.setImageResource(currentItem.getImageResource());
         holder.mTextView1.setText(currentItem.getText1());
         holder.mTextView2.setText(currentItem.getText2());
         holder.mTextView3.setText(currentItem.getText3());
}

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

    public void filterList(ArrayList<ExampleItem> filteredList) {
        mExampleList = filteredList;
        notifyDataSetChanged();
    }
}

Answer 1

您有两个列表，一个在您的活动中，另一个在您的适配器中。

过滤列表后，您只需通知适配器并仅将适配器mExampleList设置为新的已过滤列表。活动列表保持不变。

单击某个项目时，您将让该活动处理click事件。但是活动仍然有旧的，未经过滤的列表，因此它会将错误的数据发送到您的新活动。

解决方案：只需在过滤方法

中的行mExampleList = filteredList旁边添加mAdapter.filterList(filteredList);即可

使用过滤器列表

1 个答案: