问题描述
在我的应用程序中，我创建了一个自定义列表视图，我想实现一个过滤器，以便可以根据在 EditText 中输入的文本来过滤列表.我使用 BaseAdapter 作为一个单独的类，我在我的主活动中调用该类.我还在我的主要活动中实现了 addTextChangedListener()，我还在 BaseAdapter 类中实现了 getFilter().但我不知道如何使用 getFilter() 并相应地过滤我的列表.在列表中，我添加了来自 JSON URL 的值.请帮助我让我知道如何使用 getFilter() 来过滤我的列表.
In my application I have create a custom list view and I want to implement a filter so that the list can be filtered according to the text entered in the EditText. I am using a BaseAdapter as a separate class and I am calling that class in my Main Activity. I have also implemented the addTextChangedListener() in my main activity and I have also implemented the getFilter() in my BaseAdapter class. But I don't know how can I use getFilter() and can filter my list accordingly. In the list I am adding the values from a JSON URL. Please help me in letting me know that how can I use the getFilter() in order to filter my List.
Activity类的代码:
The code of Activity class:
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
lv = (ListView)findViewById(R.id.listView1);
et1 = (EditText)findViewById(R.id.editText1);
inflator = getLayoutInflater();
et1.addTextChangedListener(this);
JsonParser jParser = new JsonParser();
JSONObject json = jParser.getJSONfromUrl(url);
try
{
JSONArray explore = json.getJSONArray("explore");
for(int i=0; i<explore.length(); i++)
{
JSONObject exp = explore.getJSONObject(i);
list.add(exp.getString("username"));
}
}
catch(JSONException e)
{
e.printStackTrace();
}
srchadptr = new SearchAdapter(this, inflator, list);
lv.setAdapter(srchadptr);
}
public void afterTextChanged(Editable s) {
// TODO Auto-generated method stub
srchadptr.getFilter().filter(s);
}
public void beforeTextChanged(CharSequence s, int start, int count,
int after) {
// TODO Auto-generated method stub
}
public void onTextChanged(CharSequence s, int start, int before, int count) {
// TODO Auto-generated method stub
}
BaseAdapter 类的代码:
The code of BaseAdapter class:
public class SearchAdapter extends BaseAdapter implements Filterable {
Context context;
LayoutInflater inflater;
Button btn;
View vw;
ArrayList<String> list = new ArrayList<String>();
public SearchAdapter(Context context, LayoutInflater inflater, ArrayList<String> list) {
// TODO Auto-generated constructor stub
this.context = context;
this.inflater = inflater;
this.list = list;
}
/*public CharSequence filter(CharSequence cs) {
return cs;
}*/
public int getCount() {
// TODO Auto-generated method stub
return list.size();
}
public Object getItem(int position) {
// TODO Auto-generated method stub
return position;
}
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}
public View getView(final int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
LinearLayout ll = (LinearLayout) vw;
final EditText edt = ((EditText)ll.getChildAt(0));
vw = inflater.inflate(R.layout.list_items, null);
ImageView img = (ImageView)vw.findViewById(R.id.imageView1);
TextView tv = (TextView)vw.findViewById(R.id.textView1);
btn = (Button)vw.findViewById(R.id.button1);
tv.setText(String.valueOf(list.get(position)));
btn.setText(String.valueOf(list.get(position)));
btn.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
// TODO Auto-generated method stub
Toast.makeText(context, list.get(position), Toast.LENGTH_LONG).show();
}
});
return vw;
}
public android.widget.Filter getFilter() {
// TODO Auto-generated method stub
return new android.widget.Filter() {
@Override
protected void publishResults(CharSequence constraint, FilterResults results) {
// TODO Auto-generated method stub
}
@Override
protected FilterResults performFiltering(CharSequence constraint) {
// TODO Auto-generated method stub
return null;
}
};
}
}
提前致谢...
推荐答案
希望这个例子能帮到你
在 Main_Activity
in the Main_Activity
EditText etSearch;
BaseAdapterFilterable adapter;
etSearch.addTextChangedListener(new TextWatcher() {
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
// Listview name of the class
Listview.this.adapter.getFilter().filter(s);
}
@Override
public void beforeTextChanged(CharSequence s, int start, int count,
int after) {
// TODO Auto-generated method stub
}
@Override
public void afterTextChanged(Editable s) {
// TODO Auto-generated method stub
}
});
在您的适配器中放置此类以在 getfilter 方法中使用它
in your adapter put this class to use it in getfilter method
public class filter_here extends Filter{
@Override
protected FilterResults performFiltering(CharSequence constraint) {
// TODO Auto-generated method stub
FilterResults Result = new FilterResults();
// if constraint is empty return the original names
if(constraint.length() == 0 ){
Result.values = Original_Names;
Result.count = Original_Names.size();
return Result;
}
ArrayList<String> Filtered_Names = new ArrayList<String>();
String filterString = constraint.toString().toLowerCase();
String filterableString;
for(int i = 0; i<Original_Names.size(); i++){
filterableString = Original_Names.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) {
// TODO Auto-generated method stub
Names = (ArrayList<String>) results.values;
notifyDataSetChanged();
}
}
也在您的适配器中从 filter_here 类返回实例
also in your adapter return instance from filter_here class
@Override
public Filter getFilter() {
// TODO Auto-generated method stub
return filter;
}
这篇关于如何在 BaseAdapter 中使用 getFilter() 过滤 ListView的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！