Question

我正在使用带有自定义适配器的AutoCompleteTextView，但适配器似乎没有做任何事情。当我输入几个字母时，下拉列表不会显示。我将一些随机单词的ArrayList插入适配器。我还确保我实际上将适配器设置为textview，但没有任何反应。当我使用ArrayAdapter时，它起作用了。有人能告诉我我的代码有什么问题以及如何修复它？提前谢谢！

这是我的适配器

package com.chappota.weather.list.model;

import android.content.Context;
import android.graphics.Color;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.BaseAdapter;
import android.widget.Filter;
import android.widget.Filterable;
import android.widget.TextView;
import android.widget.Toast;

import java.util.ArrayList;

/**
 * Created by Pranav on 11/10/2014.
 */
public class CityDropDownAdapter extends BaseAdapter implements Filterable {

ArrayList<String> mList;
Context mContext;

public CityDropDownAdapter(Context ctx, ArrayList<String> list) {
    mList = list;
    mContext = ctx;
}

@Override
public int getCount() {
    return mList.size();
}

@Override
public Object getItem(int position) {
    return mList.get(position);
}

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

@Override
public View getView(int position, View convertView, ViewGroup parent) {
    View mView = convertView;
    if (mView == null) {
        LayoutInflater vi = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        mView = vi.inflate(android.R.layout.simple_dropdown_item_1line, null);
    }

    TextView suggestion = (TextView) mView.findViewById(android.R.id.text1);
    suggestion.setText(mList.get(position));
    suggestion.setTextColor(Color.BLACK);

    return mView;
}

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

private class CityFilter extends Filter {

    @Override
    public String convertResultToString(Object resultValue) {
        return (resultValue.toString());
    }

    @Override
    protected FilterResults performFiltering(CharSequence constraint) {
        if (constraint != null) {
            ArrayList<String> mData = mList;
            ArrayList<String> mSuggestions = mList;

            mSuggestions.clear();

            //Check for similarities in data from constraint
            for (String value : mData) {
                if (value.toLowerCase().contains(constraint.toString().toLowerCase())) {
                    mSuggestions.add(value);
                    Toast.makeText(mContext, value + " contains " + constraint.toString(), Toast.LENGTH_LONG).show();
                } else {
                    Toast.makeText(mContext, value + " does not " + constraint.toString(), Toast.LENGTH_LONG).show();

                }
            }

            FilterResults filterResults = new FilterResults();
            filterResults.values = mSuggestions;
            filterResults.count = mSuggestions.size();
            return filterResults;
        } else {
            return null;
        }
    }

    @Override
    protected void publishResults(CharSequence constraint, FilterResults results) {
        if (results != null && results.count > 0) {
            notifyDataSetChanged();
        }
    }
}
}

有人可以告诉我我做错了什么，以及我该如何解决？在此先感谢！

Answer 1

你在这里提供参考，

            ArrayList<String> mData = mList;
            ArrayList<String> mSuggestions = mList;

然后清除它，

           mSuggestions.clear();

这就是为什么循环没有数据而且无法正常工作的原因。

而是声明新对象，就像这样，

            ArrayList<String> mData = new ArrayList<String>(mList);
            ArrayList<String> mSuggestions = new ArrayList<String>(mList);

如何为AutoCompleteTextView使用自定义适配器

1 个答案: