列表视图过滤Android

时间:2013-02-02 16:05:18

标签: android listview search filter android-listview

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

有人可以告诉我,如果有一种方法来过滤android中的列表适配器吗?

3 个答案:

答案 0 :(得分:130)

在列表视图顶部的.xml布局文件中添加EditText。 并在您的活动/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) {}
});

这里的基本操作是在编辑文本中添加 OnTextChangeListener ,并在其回调方法中将过滤器应用到listview的适配器。

修改

要过滤到自定义BaseAdapter,您需要实施可过滤界面。

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;
    }
}

performFiltering()中,您需要将搜索查询与数据库中的值进行实际比较。它会将结果传递给 publishResults()方法。

答案 1 :(得分:9)

实施适配器Fildingrable:

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。

答案 2 :(得分:1)

如果有人对此主题感兴趣,我发现过滤列表的最佳方法是创建一个通用的Filter类,并将其与Java old school SDK包中包含的一些基本反射/泛型技术一起使用。这就是我的所作所为:

   $(str).timepicker({
        'interval': '15',
        'timeFormat': 'g:ia',
        //stepMinute: 15
    });

然后,您唯一需要做的就是将过滤器创建为成员类(可能在View&#39; onCreate&#34;中),传递适配器引用,列表和要调用过滤的方法:

public class GenericListFilter<T> extends Filter {

    /**
     * Copycat constructor
     * @param list  the original list to be used
     */
    public GenericListFilter (List<T> list, String reflectMethodName, ArrayAdapter<T> adapter) {
        super ();

        mInternalList = new ArrayList<>(list);
        mAdapterUsed  = adapter;

        try {
            ParameterizedType stringListType = (ParameterizedType)
                    getClass().getField("mInternalList").getGenericType();
            mCompairMethod =
                    stringListType.getActualTypeArguments()[0].getClass().getMethod(reflectMethodName);
        }
        catch (Exception ex) {
            Log.w("GenericListFilter", ex.getMessage(), ex);

            try {
                if (mInternalList.size() > 0) {
                    T type = mInternalList.get(0);
                    mCompairMethod = type.getClass().getMethod(reflectMethodName);
                }
            }
            catch (Exception e) {
                Log.e("GenericListFilter", e.getMessage(), e);
            }

        }
    }

    /**
     * Let's filter the data with the given constraint
     * @param constraint
     * @return
     */
    @Override protected FilterResults performFiltering(CharSequence constraint) {
        FilterResults results = new FilterResults();
        List<T> filteredContents = new ArrayList<>();

        if ( constraint.length() > 0 ) {
            try {
                for (T obj : mInternalList) {
                    String result = (String) mCompairMethod.invoke(obj);
                    if (result.toLowerCase().startsWith(constraint.toString().toLowerCase())) {
                        filteredContents.add(obj);
                    }
                }
            }
            catch (Exception ex) {
                Log.e("GenericListFilter", ex.getMessage(), ex);
            }
        }
        else {
            filteredContents.addAll(mInternalList);
        }

        results.values = filteredContents;
        results.count  = filteredContents.size();
        return results;
    }

    /**
     * Publish the filtering adapter list
     * @param constraint
     * @param results
     */
    @Override protected void publishResults(CharSequence constraint, FilterResults results) {
        mAdapterUsed.clear();
        mAdapterUsed.addAll((List<T>) results.values);

        if ( results.count == 0 ) {
            mAdapterUsed.notifyDataSetInvalidated();
        }
        else {
            mAdapterUsed.notifyDataSetChanged();
        }
    }

    // class properties
    private ArrayAdapter<T> mAdapterUsed;
    private List<T> mInternalList;
    private Method  mCompairMethod;
}

现在唯一缺少的是覆盖&#34; getFilter&#34;适配器类中的方法:

this.mFilter = new GenericFilter<MyObjectBean> (list, "getName", adapter);

全部完成!您应该成功过滤列表 - 当然,您还应该以描述您需要的最佳方式实现过滤算法,下面的代码只是一个示例。。希望它有所帮助,保重。