我有一个ListView 和一个EditText。在EditText 上键入时如何过滤 ListView 数据？
【问题讨论】：
标签： android
TextWatcher 添加到EditText#addTextChangedListener
onTextChanged 中从ListView 的适配器中添加或删除项目。如果您将 ArrayAdapter 子类化，它将具有 add 和 remove 方法【讨论】：
是的，您可以，只需实现此代码即可。使用以下代码在android中实现搜索和过滤列表：
SearchAndFilterList.java
public class SearchAndFilterList extends Activity {
private ListView mSearchNFilterLv;
private EditText mSearchEdt;
private ArrayList<String> mStringList;
private ValueAdapter valueAdapter;
private TextWatcher mSearchTw;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_search_and_filter_list);
initUI();
initData();
valueAdapter=new ValueAdapter(mStringList,this);
mSearchNFilterLv.setAdapter(valueAdapter);
mSearchEdt.addTextChangedListener(mSearchTw);
}
private void initData() {
mStringList=new ArrayList<String>();
mStringList.add("one");
mStringList.add("two");
mStringList.add("three");
mStringList.add("four");
mStringList.add("five");
mStringList.add("six");
mStringList.add("seven");
mStringList.add("eight");
mStringList.add("nine");
mStringList.add("ten");
mStringList.add("eleven");
mStringList.add("twelve");
mStringList.add("thirteen");
mStringList.add("fourteen");
mSearchTw=new TextWatcher() {
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
valueAdapter.getFilter().filter(s);
}
@Override
public void beforeTextChanged(CharSequence s, int start, int count,
int after) {
}
@Override
public void afterTextChanged(Editable s) {
}
};
}
private void initUI() {
mSearchNFilterLv=(ListView) findViewById(R.id.list_view);
mSearchEdt=(EditText) findViewById(R.id.txt_search);
}
}
自定义值适配器： ValueAdapter.java
public class ValueAdapter extends BaseAdapter implements Filterable{
private ArrayList<String> mStringList;
private ArrayList<String> mStringFilterList;
private LayoutInflater mInflater;
private ValueFilter valueFilter;
public ValueAdapter(ArrayList<String> mStringList,Context context) {
this.mStringList=mStringList;
this.mStringFilterList=mStringList;
mInflater=LayoutInflater.from(context);
getFilter();
}
//How many items are in the data set represented by this Adapter.
@Override
public int getCount() {
return mStringList.size();
}
//Get the data item associated with the specified position in the data set.
@Override
public Object getItem(int position) {
return mStringList.get(position);
}
//Get the row id associated with the specified position in the list.
@Override
public long getItemId(int position) {
return position;
}
//Get a View that displays the data at the specified position in the data set.
@Override
public View getView(int position, View convertView, ViewGroup parent) {
Holder viewHolder;
if(convertView==null) {
viewHolder=new Holder();
convertView=mInflater.inflate(R.layout.list_item,null);
viewHolder.nameTv=(TextView)convertView.findViewById(R.id.txt_listitem);
convertView.setTag(viewHolder);
}else{
viewHolder=(Holder)convertView.getTag();
}
viewHolder.nameTv.setText(mStringList.get(position).toString());
return convertView;
}
private class Holder{
TextView nameTv;
}
//Returns a filter that can be used to constrain data with a filtering pattern.
@Override
public Filter getFilter() {
if(valueFilter==null) {
valueFilter=new ValueFilter();
}
return valueFilter;
}
private class ValueFilter extends Filter {
//Invoked in a worker thread to filter the data according to the constraint.
@Override
protected FilterResults performFiltering(CharSequence constraint) {
FilterResults results=new FilterResults();
if(constraint!=null && constraint.length()>0){
ArrayList<String> filterList=new ArrayList<String>();
for(int i=0;i<mStringFilterList.size();i++){
if(mStringFilterList.get(i).contains(constraint)) {
filterList.add(mStringFilterList.get(i));
}
}
results.count=filterList.size();
results.values=filterList;
}else{
results.count=mStringFilterList.size();
results.values=mStringFilterList;
}
return results;
}
//Invoked in the UI thread to publish the filtering results in the user interface.
@SuppressWarnings("unchecked")
@Override
protected void publishResults(CharSequence constraint,
FilterResults results) {
mStringList=(ArrayList<String>) results.values;
notifyDataSetChanged();
}
}
activity_search_and_filter_list.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<EditText
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id="@+id/txt_search"
tools:context=".SearchAndFilterList"
android:hint="Enter text to search" />
<ListView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/list_view"
android:layout_below="@+id/txt_search"></ListView>
</RelativeLayout>
list_item.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/txt_listitem"/>
</RelativeLayout>
AndroidManifext.xml
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.searchandfilterlistview"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="15" />
<application
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name=".SearchAndFilterList"
android:label="@string/title_activity_search_and_filter_list" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
我希望这段代码将有助于实现自定义搜索和过滤列表视图。
【讨论】：
你可以使用：
http://developer.android.com/reference/android/widget/TextView.html
addTextChangedListener( TextWatcher watcher )
找出文本视图何时更改。我相信每次添加或删除字母时都应该调用它。
然后更新您的列表适配器以显示新项目：
BaseAdapter 的子类来接受您的过滤器，并在它完成删除您不再需要的项目后调用notifyDataSetChanged()
http://developer.android.com/reference/android/widget/BaseAdapter.html
【讨论】：
根据 EditText 中的输入搜索列表视图
public class MainActivity extends Activity {
private ListView lv,lv2;
private EditText et;
String listview_array[]={"01634 ABOHAR","080 Bangalore","011 Delhi","Dell Inspiron", "HTC One X", "HTC Wildfire S", "HTC Sense", "1234", "iPhone 4S", "Samsung Galaxy Note 800", "Samsung Galaxy S3", "MacBook Air", "Mac Mini", "MacBook Pro"};
private ArrayList<String> array_sort = new ArrayList<String>();
int textlength = 0;
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
lv = (ListView) findViewById(R.id.ListView01);
lv2 = (ListView) findViewById(R.id.ListView02);
et = (EditText) findViewById(R.id.EditText01);
lv.setAdapter(new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, listview_array));
int x= lv.getHeaderViewsCount ();
System.out.println("x========"+x);
lv.setAdapter(new ArrayAdapter<String>
(MainActivity.this,
android.R.layout.simple_list_item_1, listview_array));
et.addTextChangedListener(new TextWatcher()
{
public void afterTextChanged(Editable s)
{
// Abstract Method of TextWatcher Interface.
}
public void beforeTextChanged(CharSequence s,
int start, int count, int after)
{
// Abstract Method of TextWatcher Interface.
}
public void onTextChanged(CharSequence s,
int start, int before, int count)
{
textlength = et.getText().length();
array_sort.clear();
for (int i = 0; i < listview_array.length; i++)
{
if (textlength <= listview_array[i].length())
{
String s2= et.getText().toString();
if(listview_array[i].toString().contains(et.getText().toString()))
{
array_sort.add(listview_array[i]);
}
}
}
lv.setAdapter(new ArrayAdapter<String>
(MainActivity.this,
android.R.layout.simple_list_item_1, array_sort));
}
});
}
}
对于基于类项的自定义列表视图中的搜索，请参阅链接implement search on a custom listview。根据您的需要进行修改。
【讨论】：
当你使用自定义列表视图时
适配器：
public class Adapter extends ArrayAdapter {
ArrayList<String> list = new ArrayList<>();
ArrayList<String> filteredData = new ArrayList<>();
public Adapter(@NonNull Context context, int resource) {
super(context, resource);
}
@NonNull
@Override
public View getView(int position, @Nullable View convertView, @NonNull ViewGroup parent) {
LayoutInflater inflate = (LayoutInflater) getSystemService(LAYOUT_INFLATER_SERVICE);
@SuppressLint("ViewHolder") View vi = inflate.inflate(R.layout.ly_items, null);
try {
JSONObject js = new JSONObject(list.get(position));
TextView txtItem = vi.findViewById(R.id.txtItem);
ImageView imgItem = vi.findViewById(R.id.imgItem);
txtItem.setText(js.getString("name") + " - " + js.getInt("number"));
Picasso.get().load(js.getString("logo_url")).into(imgItem);
} catch (JSONException e) {
e.printStackTrace();
}
return vi;
}
@Override
public void add(@Nullable Object object) {
super.add(object);
list.add(object.toString());
filteredData.add(object.toString());
}
@Override
public int getCount() {
return list.size();
}
@Nullable
@Override
public Object getItem(int position) {
return list.get(position);
}
public void filter(String charText) {
charText = charText.toLowerCase(Locale.getDefault());
list.clear();
if (charText.length() == 0) {
list.addAll(filteredData);
} else {
for (String wp : filteredData) {
try {
JSONObject json = new JSONObject(wp);
if (json.getString("name").toLowerCase().contains(charText) || json.getString("number").contains(charText)) {
list.add(wp);
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}
notifyDataSetChanged();
}
}
还有你的班级：
Adapter adapter;
ListView list;
EditText edtSearch;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
list = findViewById(R.id.list);
edtSearch = findViewById(R.id.edtSearch);
adapter = new Adapter(this, android.R.layout.simple_list_item_1);
list.setAdapter(adapter);
edtSearch.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
adapter.filter(s.toString());
}
@Override
public void afterTextChanged(Editable s) {
}
});
}
【讨论】：
1) 为您的列表视图创建一个自定义适配器并创建一个 removeIfMatch(String s) 方法：
public void removeIfMatch(String s) {
for item in adapter:
if item.matches(s) {
data.removeItem(item);
notifyDataSetChanged();
break
}
}
2) 当 EditText 内容改变时创建回调
3) 调用 adapter.removeIfMatch(editText.getText())
【讨论】：