安卓 ListFragment : Implementing a search EditText

Question

我还是 fragments 的新手，我需要添加一个动态搜索框来过滤 ListView 项，同时用户在编辑框中键入内容。我尝试了开发者文档 https://developer.android.com/training/search/setup.html但它只是将搜索小部件添加到操作栏，我想将搜索功能添加到编辑文本框。我正在使用 ListFragment 来处理项目上的点击事件。

这是我的代码。

ActivityMain.java

@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    mToolbar = (Toolbar) findViewById(R.id.app_bar);
    setSupportActionBar(mToolbar);

    FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
    fragmentTransaction.replace(R.id.main_container, new FragmentNamesList()).commit();

}

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">
<android.support.v7.widget.Toolbar
    android:id="@+id/app_bar"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@color/colorPrimary"
    android:minHeight="?attr/actionBarSize"
    app:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">

</android.support.v7.widget.Toolbar>

<LinearLayout
    android:id="@+id/main_container"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

</LinearLayout>

</LinearLayout>

fragment 名称列表.java

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        getActivity().getSupportFragmentManager().beginTransaction().replace(R.id.list_container, new FragmentNames()).commit();
        return inflater.inflate(R.layout.frag_names_list, container, false);

fragment 名称列表.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent">
<LinearLayout
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_gravity="center_horizontal"
    android:layout_marginBottom="15dp">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textAppearance="?android:attr/textAppearanceLarge"
        android:text="Large Text"
        android:id="@+id/textView"
        android:layout_gravity="center_horizontal"
        android:layout_marginTop="25dp" />

    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/et_search"
        android:layout_gravity="center_horizontal"
        android:layout_marginLeft="15dp"
        android:layout_marginRight="15dp"
        android:hint="Search" />
</LinearLayout>

<LinearLayout android:id="@+id/list_container"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:orientation="vertical"
    android:layout_marginLeft="15dp"
    android:layout_marginRight="15dp">

</LinearLayout>

</LinearLayout>

我在单独的布局中有 ListView

frag_list_test.xml

<?xml version="1.0" encoding="utf-8"?>
<ListView xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/list_test">

</ListView>

fragment 名称.java

public static String[] mValues = new String[]{"Item 1", "Item 2", "Item 3"};

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.frag_list_test, container, false);
ArrayAdapter<String> adapter = new ArrayAdapter<String>(getActivity(), android.R.layout.simple_list_item_1, mValues);
setListAdapter(adapter);
        return rootView;
    }

Answer 1

像往常一样创建您的 ListView ，但在您的 ListView 适配器中，实现 filterable 接口(interface):

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;
    }
}

您需要在performFiltering 方法中实现过滤逻辑。它将其结果传递给 publishResults。

根据布局中的 ListView 和 EditText，您可以使用如下内容:

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

// Adding items to listview
adapter = new CustomAdapter(...);
lv.setAdapter(adapter);       
inputSearch.addTextChangedListener(new TextWatcher() {

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

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

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

这应该为您提供所需内容的要点。