这是代码，我使用了一个自定义适配器，并应用了 Filter 方法，现在当输入退格键时，ListView 不会更新，当一个人从项目 Activity 切换回来时。我读到它是过滤器中的一个错误，但我该如何绕过它，我知道已经实现了我想要的这种设置的应用程序。

public class IndexPageActivity extends Activity implements OnItemClickListener{ 
    ListView listView;
    EditText editTextB;
    PagesAdapter adapter1;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);
        listView = (ListView) findViewById(R.id.pageList);
        editTextB = (EditText) findViewById(R.id.searchB);
        adapter1 = new PagesAdapter(this);
        listView.setAdapter(adapter1);
        adapter1.notifyDataSetChanged();
        listView.setOnItemClickListener(this);

        editTextB.addTextChangedListener(new TextWatcher() {
            @Override
            public void onTextChanged(CharSequence cs, int arg1, int arg2, int arg3) {
                IndexPageActivity.this.adapter1.getFilter().filter(cs.toString());
                adapter1.notifyDataSetChanged();
            }

            @Override
            public void beforeTextChanged(CharSequence arg0, int arg1,
                        int arg2, int arg3) { }

            @Override
            public void afterTextChanged(Editable arg0) { }
        });
    }

    @Override
    public void onItemClick(AdapterView<?> arg0, View v, int position, long arg3) {
        Intent i;
        String name = adapter1.getItem(position);
        Log.d("id", name);

        if (name.equals("Item1"))
        {
            i = new Intent(this, anActivity.class);
            startActivity(i);
        }
        else if (name.equals("Item2"))
        {
            i = new Intent(this, anActivity2.class);
            startActivity(i);
        }
    }
}

class SingleRow {
    String pagedata;
    SingleRow(String pagedata){
        this.pagedata=pagedata;
    }
}
class PagesAdapter extends BaseAdapter implements Filterable{
    ArrayList<String> pagelist;
    List<String> arrayList;
    Context context;
    String [] pagedatas;

    PagesAdapter(Context c){
        context=c;
        pagelist = new ArrayList<String>();
        Resources res = c.getResources();
        pagedatas = res.getStringArray(R.array.pages_data);
        for (int i=0;i<463;i++){
            pagelist.add(pagedatas[i]);
        }
    }
    @Override
    public int getCount() {
        return pagelist.size();
    }

    @Override
    public String getItem(int i) {
        return pagelist.get(i);
    }

    @Override
    public long getItemId(int i) {
        return i;
    }

    @Override
    public View getView(int i, View view, ViewGroup viewG) {
        LayoutInflater inflater=(LayoutInflater)             context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        View row=inflater.inflate(R.layout.single_row,viewG,false);
        TextView pagetitle = (TextView) row.findViewById(R.id.textViewRow);

        String temp=pagelist.get(i);

        pagetitle.setText(temp);
        return row;
    }

    public class filter_here extends Filter{
        @Override
        protected FilterResults performFiltering(CharSequence constraint) {
            FilterResults Result = new FilterResults();
            // if constraint is empty return the original names
            if(constraint.length() == 0 ){
                Result.values = pagelist;
                Result.count = pagelist.size();
                return Result;
            }

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

            for(int i = 0; i<pagelist.size(); i++){
                filterableString = pagelist.get(i);
                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) {
            pagelist = (ArrayList<String>) results.values;
            notifyDataSetChanged();
        }
    }

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

最佳答案

1) 退格过滤

在您的 publishResults 中，您正在修改您的 pagelist，因此如果您按退格键并再次过滤，pagelist 仅包含一小部分原始的 pagelist 条目:

因此，您需要保留原始数据的副本!像这样的东西:

List<String> allData;

PagesAdapter(Context c) {
    ...
    allData = pagelist;
    ...
}

并在您的过滤器方法中，使用 allData 对象:

for (int i = 0; i < allData.size(); i++) {
    filterableString = allData.get(i);
    if (filterableString.toLowerCase().contains(filterString)) {
        Filtered_Names.add(filterableString);
    }
}

以及您将数据重置为原始数据的位置:

// if constraint is empty return the original names
if (constraint.length() == 0) {
    Result.values = allData;
    Result.count = allData.size();
    return Result;
}

2) 从另一个 Activity 返回后清除过滤器:

这可以在 onResume 中完成...就个人而言，我会清除 editText 中的文本以像这样重置过滤器:

@Override
protected void onResume() {
    if (editTextB != null) {
        editTextB.setText("");
    }
    super.onResume();
}

关于android - 绕过过滤不更新ListView Android的bug，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/20146760/