列表视图过滤Android

Question

我在android中创建了一个列表视图,我想在列表上方添加编辑文本,当用户输入文本时,列表将根据用户输入进行过滤

任何人都可以告诉我,如果有一种方法来过滤android中的列表适配器？

Answer 1

是.在listl的aml布局文件中添加EditText.在你的活动/片段..

lv = (ListView) findViewById(R.id.list_view);
    inputSearch = (EditText) findViewById(R.id.inputSearch);

// Adding items to listview
adapter = new ArrayAdapter<String>(this, R.layout.list_item, R.id.product_name,    products);
lv.setAdapter(adapter);       
inputSearch.addTextChangedListener(new TextWatcher() {

    @Override
    public void onTextChanged(CharSequence cs, int arg1, int arg2, int arg3) {
        // When user changed the Text
        MainActivity.this.adapter.getFilter().filter(cs);
    }

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

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

这里的基本操作是将OnTextChangeListener添加到编辑文本中,并在其回调方法中将过滤器应用于listview的适配器.

编辑

要获得自定义BaseAdapter的过滤器,您需要实现Filterable接口.

class CustomAdapter extends BaseAdapter implements Filterable {

    public View getView(){
    ...
    }
    public Integer getCount()
    {
    ...
    }

    @Override
    public Filter getFilter() {

        Filter filter = new Filter() {

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

                arrayListNames = (List<String>) results.values;
                notifyDataSetChanged();
            }

            @Override
            protected FilterResults performFiltering(CharSequence constraint) {

                FilterResults results = new FilterResults();
                ArrayList<String> FilteredArrayNames = new ArrayList<String>();

                // perform your search here using the searchConstraint String.

                constraint = constraint.toString().toLowerCase();
                for (int i = 0; i < mDatabaseOfNames.size(); i++) {
                    String dataNames = mDatabaseOfNames.get(i);
                    if (dataNames.toLowerCase().startsWith(constraint.toString()))  {
                        FilteredArrayNames.add(dataNames);
                    }
                }

                results.count = FilteredArrayNames.size();
                results.values = FilteredArrayNames;
                Log.e("VALUES", results.values.toString());

                return results;
            }
        };

        return filter;
    }
}

在perfromFiltering()内部,您需要将搜索查询与数据库中的值进行实际比较.它会将其结果传递给 publishResults()方法.

Answer 2

实现适配器可过滤:

public class vJournalAdapter extends ArrayAdapter<JournalModel> implements Filterable{
private ArrayList<JournalModel> items;
private Context mContext;
....

然后创建您的Filter类:

private class JournalFilter extends Filter{

    @Override
    protected FilterResults performFiltering(CharSequence constraint) {
        FilterResults result = new FilterResults();
        List<JournalModel> allJournals = getAllJournals();
        if(constraint == null || constraint.length() == 0){

            result.values = allJournals;
            result.count = allJournals.size();
        }else{
            ArrayList<JournalModel> filteredList = new ArrayList<JournalModel>();
            for(JournalModel j: allJournals){
                if(j.source.title.contains(constraint))
                    filteredList.add(j);
            }
            result.values = filteredList;
            result.count = filteredList.size();
        }

        return result;
    }
    @SuppressWarnings("unchecked")
    @Override
    protected void publishResults(CharSequence constraint, FilterResults results) {
        if (results.count == 0) {
            notifyDataSetInvalidated();
        } else {
            items = (ArrayList<JournalModel>) results.values;
            notifyDataSetChanged();
        }
    }

}

这样,您的适配器是可过滤的,您可以将过滤器项目传递给适配器的过滤器并完成工作.我希望这会有所帮助.