我如何使用 baseadapter 过滤列表视图
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【中文标题】我如何使用 baseadapter 过滤列表视图【英文标题】：How could i filter the listview using baseadapter 【发布时间】：2013-07-17 05:27:41 【问题描述】：我正在尝试过滤列表视图，但 getfilter 方法不起作用，
代码如下：
@Override
public void afterTextChanged(Editable s)
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after)
@Override
public void onTextChanged(CharSequence s, int start, int before, int count)
mHistoryAdapter.getFilter().filter(s);
我也在baseadapter中添加了方法
public Filter getFilter()
return null;
但它不起作用..有人可以帮帮我吗..@谢谢
【问题讨论】：
***.com/questions/17328955/…。 developer.android.com/reference/android/widget/BaseAdapter.html。定义自定义过滤器 @Raghunandan 我尝试添加该内容但出现错误 错误是什么。发布堆栈跟踪。 每次更改都可以手动过滤列表视图内容。 @Raghunandan 我有数据数组列表，我该如何过滤它 【参考方案1】：MainActivity.java
public class MainActivity extends Activity
private ListView mListView;
private CustomAdapter mCustomAdapter;
private EditText mEditText;
private ArrayList<Contacts> _Contacts = new ArrayList<Contacts>();
@Override
protected void onCreate(Bundle savedInstanceState)
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
for (int i = 0; i < 100; i++)
Contacts contacts = new Contacts();
contacts.setId(""+i);
contacts.setName("Name "+i);
_Contacts.add(contacts);
mListView = (ListView) findViewById(R.id.listView1);
mEditText = (EditText) findViewById(R.id.editText1);
mCustomAdapter = new CustomAdapter(MainActivity.this, _Contacts);
mListView.setAdapter(mCustomAdapter);
mEditText.addTextChangedListener(new TextWatcher()
@Override
public void onTextChanged(CharSequence arg0, int arg1, int arg2, int arg3)
mCustomAdapter.getFilter().filter(arg0);
@Override
public void beforeTextChanged(CharSequence arg0, int arg1, int arg2,
int arg3)
@Override
public void afterTextChanged(Editable arg0)
);
CustomAdapter.java
public class CustomAdapter extends BaseAdapter implements Filterable
private ArrayList<Contacts> _Contacts;
private Activity context;
private LayoutInflater inflater;
private ValueFilter valueFilter;
private ArrayList<Contacts> mStringFilterList;
public CustomAdapter(Activity context, ArrayList<Contacts> _Contacts)
super();
this.context = context;
this._Contacts = _Contacts;
mStringFilterList = _Contacts;
this.inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
getFilter();
@Override
public int getCount()
return _Contacts.size();
@Override
public Object getItem(int position)
return _Contacts.get(position).getName();
@Override
public long getItemId(int position)
return 0;
public class ViewHolder
TextView tname, tplace;
@Override
public View getView(int position, View convertView, ViewGroup parent)
ViewHolder holder;
if (convertView == null)
holder = new ViewHolder();
convertView = inflater.inflate(R.layout.activity_main, null);
holder.tname = (TextView) convertView.findViewById(R.id.textView1);
holder.tplace = (TextView) convertView.findViewById(R.id.textView2);
convertView.setTag(holder);
else
holder = (ViewHolder) convertView.getTag();
holder.tname.setText("" + _Contacts.get(position).getName());
holder.tplace.setText("" + "" + _Contacts.get(position).getId());
return convertView;
@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<Contacts> filterList=new ArrayList<Contacts>();
for(int i=0;i<mStringFilterList.size();i++)
if((mStringFilterList.get(i).getName().toUpperCase())
.contains(constraint.toString().toUpperCase()))
Contacts contacts = new Contacts();
contacts.setName(mStringFilterList.get(i).getName());
contacts.setId(mStringFilterList.get(i).getId());
filterList.add(contacts);
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)
_Contacts=(ArrayList<Contacts>) results.values;
notifyDataSetChanged();
Contacts.java
public class Contacts
private String name;
private String id;
public String getName()
return name;
public void setName(String name)
this.name = name;
public String getId()
return id;
public void setId(String id)
this.id = id;
main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_
android:layout_
android:orientation="vertical" >
<EditText
android:id="@+id/editText1"
android:layout_
android:layout_
android:ems="10" >
<requestFocus />
</EditText>
<ListView
android:id="@+id/listView1"
android:layout_
android:layout_ >
</ListView>
activity_main.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_
android:layout_
android:layout_marginBottom="2dp"
android:layout_marginLeft="1dp"
android:layout_marginRight="1dp"
android:layout_marginTop="2dp"
android:background="@android:color/black"
android:gravity="center_vertical"
android:paddingBottom="2dp"
android:paddingTop="2dp"
tools:context=".MainActivity" >
<TextView
android:id="@+id/textView1"
android:layout_
android:layout_
android:layout_marginLeft="8dp"
android:text="Large Text"
android:textAppearance="?android:attr/textAppearanceLarge"
android:textColor="@android:color/white" />
<TextView
android:id="@+id/textView2"
android:layout_
android:layout_
android:layout_marginLeft="8dp"
android:text="Small Text"
android:textAppearance="?android:attr/textAppearanceSmall"
android:textColor="@android:color/white" />
这是一个示例项目代码。使用此代码，这将真正帮助您
【讨论】：
您的代码在过滤器类中初始化联系人两次，而是直接使用此 filterList.add(mStringFilterList.get( index )); 工作完美。只是根据我的要求修改了代码。竖起大拇指。 对列表进行过滤，但在逐个删除字符时不返回原始状态。 您的回答对我有很大帮助，但我现在无法将 listview 项目传递给他发送另一个项目的另一个活动。 @rodrigo.oliveira 您需要在列表视图项目单击侦听器中使用 mCustomAdpter.getItem(position) 以获得正确的值。希望这会有所帮助。【参考方案2】：给你。一个简单的基础适配器（无视图回收），它将显示和过滤一些自定义任意对象的列表。在此示例中，Object.name 是我们将用于过滤的字段。
1) 在您的活动中，（或）您创建 ListView 的位置，启用文本过滤：
class MyObject
public String name;
List<MyObject> myData = ArrayList<>();
listview.setTextFilterEnabled(true);
2) 正如您已经注意到的，在 Edittext 的 textwatcher 中，触发 ListAdapter 上的过滤器：
public void onTextChanged(CharSequence s, int start, int before, int count)
listadapter.getFilter().filter(s);
3) 在您的基本适配器中，implement Filterable。并存储两份数据，一份是原始的，一份是过滤的。 确保访问整个 BaseAdapter 中的过滤数据，而不是未过滤的数据
public class FilterableListAdapterExample extends BaseAdapter implements Filterable
private List<MyObject> mData; //the original data
private List<MyObject> mDataFiltered;//the filtered data
private LayoutInflater mLayoutInflater;
public FilterableListAdapterExample(Context context, List<MyObject> data)
mData = data;
mDataFiltered=data;
mLayoutInflater = LayoutInflater.from(context);
@Override
public View getView(int position, View convertView, ViewGroup parent)
convertView= mLayoutInflater.inflate(R.layout.listview_item, null);
TextView textview=(TextView)convertView.findViewById(R.id.listitem_textview);
//note: we access mDataFiltered, not mData
textview.setText(mDataFiltered.get(position).name);
return convertView;
@Override
public long getItemId(int position)
return position;
@Override
public int getCount()
return mDataFiltered.size();
@Override
public Filter getFilter()
return new Filter()
@Override
protected FilterResults performFiltering(CharSequence constraint)
FilterResults results = new FilterResults();
if (constraint == null || constraint.length() == 0)
//no constraint given, just return all the data. (no search)
results.count = mData.size();
results.values = mData;
else //do the search
List<MyObject> resultsData = new ArrayList<>();
String searchStr = constraint.toString().toUpperCase();
for (MyObject o : mData)
if (o.name.toUpperCase().startsWith(searchStr)) resultsData.add(o);
results.count = resultsData.size();
results.values = resultsData;
return results;
@Override
protected void publishResults(CharSequence constraint, FilterResults results)
mDataFiltered = (ArrayList<MyObject>) results.values;
notifyDataSetChanged();
;
【讨论】：
嗨@Mtl Dev。我遵循相同的代码。但我收到此错误 java.lang.NullPointerException: Attempt to invoke virtual method 'android.widget.Filter deyapay.bodaty.com.sampledisplay.Splitadapter.getFilter()' on an null object reference。在这个地方 mCustomAdapter.getFilter().filter(cs.toString());为什么会发生？ 听起来您在尝试使用之前还没有创建对象“mCustomAdapter”。 不，我为适配器类创建了对象 检查是否创建成功，通过测试看看你的对象==null【参考方案3】：
请尝试以下可能对您有帮助的代码：
public class MainActivity extends ListActivity
private List<String> list = new ArrayList<String>();
List<String> mOriginalValues;
@Override
public void onCreate(Bundle savedInstanceState)
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
final MyAdapter adapter = new MyAdapter(this, getModel());
setListAdapter(adapter);
EditText filterEditText = (EditText) findViewById(R.id.filterText);
// Add Text Change Listener to EditText
filterEditText.addTextChangedListener(new TextWatcher()
@Override
public void onTextChanged(CharSequence s, int start, int before, int count)
// Call back the Adapter with current character to Filter
adapter.getFilter().filter(s.toString());
@Override
public void beforeTextChanged(CharSequence s, int start, int count,int after)
@Override
public void afterTextChanged(Editable s)
);
private List<String> getModel()
list.add("Linux");
list.add("Windows7");
list.add("Suse");
list.add("Eclipse");
list.add("Ubuntu");
list.add("Solaris");
list.add("Android");
list.add("iPhone");
list.add("Windows XP");
return list;
// Adapter Class
public class MyAdapter extends BaseAdapter implements Filterable
List<String> arrayList;
List<String> mOriginalValues; // Original Values
LayoutInflater inflater;
public MyAdapter(Context context, List<String> arrayList)
this.arrayList = arrayList;
inflater = LayoutInflater.from(context);
@Override
public int getCount()
return arrayList.size();
@Override
public Object getItem(int position)
return position;
@Override
public long getItemId(int position)
return position;
private class ViewHolder
TextView textView;
@Override
public View getView(int position, View convertView, ViewGroup parent)
ViewHolder holder = null;
if (convertView == null)
holder = new ViewHolder();
convertView = inflater.inflate(R.layout.row, null);
holder.textView = (TextView) convertView
.findViewById(R.id.listTxt);
convertView.setTag(holder);
else
holder = (ViewHolder) convertView.getTag();
holder.textView.setText(arrayList.get(position));
return convertView;
@Override
public Filter getFilter()
Filter filter = new Filter()
@SuppressWarnings("unchecked")
@Override
protected void publishResults(CharSequence constraint,FilterResults results)
arrayList = (List<String>) results.values; // has the filtered values
notifyDataSetChanged(); // notifies the data with new filtered values
@Override
protected FilterResults performFiltering(CharSequence constraint)
FilterResults results = new FilterResults(); // Holds the results of a filtering operation in values
List<String> FilteredArrList = new ArrayList<String>();
if (mOriginalValues == null)
System.out.println("");
mOriginalValues = new ArrayList<String>(arrayList); // saves the original data in mOriginalValues
/********
*
* If constraint(CharSequence that is received) is null returns the mOriginalValues(Original) values
* else does the Filtering and returns FilteredArrList(Filtered)
*
********/
if (constraint == null || constraint.length() == 0)
// set the Original result to return
results.count = mOriginalValues.size();
results.values = mOriginalValues;
else
constraint = constraint.toString().toLowerCase();
for (int i = 0; i < mOriginalValues.size(); i++)
String data = mOriginalValues.get(i);
if (data.toLowerCase().startsWith(constraint.toString()))
FilteredArrList.add(data);
// set the Filtered result to return
results.count = FilteredArrList.size();
results.values = FilteredArrList;
return results;
;
return filter;
【讨论】：
这对我很有帮助。【参考方案4】：在你的 baseadapter 类中实现 Filterable。
public class MainActivity extends AppCompatActivity
String names[] = "Apple","Banana","Kiwi","Oranges","Watermelon";
String emails[] = "This is apple","This is banana","This is kiwi","This is oranges","This is watermelon";
int images[] = R.drawable.apple,R.drawable.banana,R.drawable.kiwi,R.drawable.oranges,R.drawable.watermelon;
List<ItemsModel> itemsModelList = new ArrayList<>();
ListView listView;
CustomAdapter customAdapter;
@Override
protected void onCreate(Bundle savedInstanceState)
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
listView = findViewById(R.id.listview);
for(int i = 0;i < names.length;i++)
ItemsModel itemsModel = new ItemsModel(names[i],emails[i],images[i]);
itemsModelList.add(itemsModel);
customAdapter = new CustomAdapter(itemsModelList,this);
listView.setAdapter(customAdapter);
@Override
public boolean onCreateOptionsMenu(Menu menu)
getMenuInflater().inflate(R.menu.search_menu,menu);
MenuItem menuItem = menu.findItem(R.id.searchView);
SearchView searchView = (SearchView) menuItem.getActionView();
searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener()
@Override
public boolean onQueryTextSubmit(String query)
return false;
@Override
public boolean onQueryTextChange(String newText)
Log.e("Main"," data search"+newText);
customAdapter.getFilter().filter(newText);
return true;
);
return true;
@Override
public boolean onOptionsItemSelected(@NonNull MenuItem item)
int id = item.getItemId();
if(id == R.id.searchView)
return true;
return super.onOptionsItemSelected(item);
public class CustomAdapter extends BaseAdapter implements Filterable
private List<ItemsModel> itemsModelsl;
private List<ItemsModel> itemsModelListFiltered;
private Context context;
public CustomAdapter(List<ItemsModel> itemsModelsl, Context context)
this.itemsModelsl = itemsModelsl;
this.itemsModelListFiltered = itemsModelsl;
this.context = context;
@Override
public int getCount()
return itemsModelListFiltered.size();
@Override
public Object getItem(int position)
return itemsModelListFiltered.get(position);
@Override
public long getItemId(int position)
return position;
@Override
public View getView(final int position, View convertView, ViewGroup parent)
View view = getLayoutInflater().inflate(R.layout.row_items,null);
TextView names = view.findViewById(R.id.name);
TextView emails = view.findViewById(R.id.email);
ImageView imageView = view.findViewById(R.id.images);
names.setText(itemsModelListFiltered.get(position).getName());
emails.setText(itemsModelListFiltered.get(position).getEmail());
imageView.setImageResource(itemsModelListFiltered.get(position).getImages());
view.setOnClickListener(new View.OnClickListener()
@Override
public void onClick(View v)
Log.e("main activity","item clicked");
startActivity(new Intent(MainActivity.this,ItemsPreviewActivity.class).putExtra("items",itemsModelListFiltered.get(position)));
);
return view;
@Override
public Filter getFilter()
Filter filter = new Filter()
@Override
protected FilterResults performFiltering(CharSequence constraint)
FilterResults filterResults = new FilterResults();
if(constraint == null || constraint.length() == 0)
filterResults.count = itemsModelsl.size();
filterResults.values = itemsModelsl;
else
List<ItemsModel> resultsModel = new ArrayList<>();
String searchStr = constraint.toString().toLowerCase();
for(ItemsModel itemsModel:itemsModelsl)
if(itemsModel.getName().contains(searchStr) || itemsModel.getEmail().contains(searchStr))
resultsModel.add(itemsModel);
filterResults.count = resultsModel.size();
filterResults.values = resultsModel;
return filterResults;
@Override
protected void publishResults(CharSequence constraint, FilterResults results)
itemsModelListFiltered = (List<ItemsModel>) results.values;
notifyDataSetChanged();
;
return filter;
您可以在此处获得有关如何使用搜索和 onItemClickListener 实现列表视图的完整教程：
Listview with search/filter and onItemClickListener
Source files
【讨论】：
【参考方案5】：我觉得这里不需要getfilter()方法
ArrayList<YourDataModel> data;
.
.
.
Collections.sort(data, new Comparator<YourDataModel>()
@Override
public int compare(YourDataModel data1, YourDataModel data2)
if( data1.getDistance() < data2.getDistance() )
return 1;
else
return 0;
);
.
.
.
ListView lvData = (ListView) findViewById(R.id.listview1);
MyCustomAdapter adapter = new MyCustomAdapter(this, R.layout.listview_item_row, data);
lvData.setAdapter(adapter);
并在您想要更新时使用notifydatachange 方法
【讨论】：
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