如何在Android中实现列表视图的搜索功能

Question

我是Android的新手，我需要为listview做一个搜索功能。 请告诉我如何编写代码以及将代码放在哪里。 这是我的listview java类，布局文件和Dbhelper类。

View_Guest.java

public class View_Guest extends AppCompatActivity implements View.OnClickListener {

    ListView guestList;

    DBhelper helper;
    SQLiteDatabase db;
    Toolbar toolbar;
    String selected_id;
    String gt;

    SimpleCursorAdapter adapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_view_guest);

        toolbar = (Toolbar)findViewById(R.id.tool_bar);
        setSupportActionBar(toolbar);

        getSupportActionBar().setDisplayHomeAsUpEnabled(true);
        getSupportActionBar().setHomeButtonEnabled(true);

        guestList = (ListView) findViewById(R.id.lblguestlist);

        guestList.setOnItemClickListener(new AdapterView.OnItemClickListener() {

            @Override
            public void onItemClick(final AdapterView<?> arg0, View arg1, final int position, long arg3) {

                Cursor row1= (Cursor) arg0.getItemAtPosition(position);
                selected_id = row1.getString(0);
                gt=row1.getString(0);


                Intent myIntent = new Intent(View_Guest.this, Guest.class);
                myIntent.putExtra("data key", gt);
                startActivity(myIntent);

            }
        });

        helper = new DBhelper(this);

        fetchdata();
    }

    public void fetchdata(){

        db = helper.getReadableDatabase();
        Cursor c = db.query(DBhelper.TABLE, null, null, null, null, null, null);

        adapter = new SimpleCursorAdapter(
                this,
                R.layout.guest_row,
                c,
                new String[]{DBhelper.C_NAME, DBhelper.C_COUNT, DBhelper.C_INVITE},

                new int[]{R.id.guestrowname, R.id.guestrowcount, R.id.guestrowinvite});

        guestList.setAdapter(adapter);

    }

activity_view_guest.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"
tools:context="com.example.ddk.weddingplanner.View_Guest">

<include
    android:id="@+id/tool_bar"
    layout="@layout/tool_bar"></include>

<TextView
    android:layout_width="200dp"
    android:layout_height="40dp"
    android:textAppearance="?android:attr/textAppearanceSmall"
    android:text="Guest Name"
    android:id="@+id/guestrowname"
    android:layout_marginLeft="10dp"
    android:layout_below="@+id/tool_bar" />
    <!--android:textColor="@drawable/abc_item_background_holo_dark"-->


<TextView
    android:layout_width="wrap_content"
    android:layout_height="40dp"
    android:textAppearance="?android:attr/textAppearanceSmall"
    android:text="Count"
    android:id="@+id/guestrowcount"
    android:layout_marginLeft="10dp"
    android:layout_toEndOf="@+id/guestrowname"
    android:layout_toRightOf="@+id/guestrowname"
    android:layout_below="@+id/tool_bar"/>

<TextView
    android:layout_width="wrap_content"
    android:layout_height="50dp"
    android:textAppearance="?android:attr/textAppearanceSmall"
    android:text="Invite"
    android:id="@+id/guestrowinvite"
    android:layout_marginLeft="40dp"
    android:layout_toEndOf="@+id/guestrowcount"
    android:layout_toRightOf="@+id/guestrowcount"
    android:layout_below="@+id/tool_bar"/>

<ListView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/lblguestlist"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true"
    android:layout_below="@+id/guestrowname" />

<SearchView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/searchView"
    android:layout_alignBottom="@+id/tool_bar"
    android:layout_centerHorizontal="true" />

DBhelper.java

public class DBhelper extends SQLiteOpenHelper {


static final String DATABASE = "wedding4.db";
static final int VERSION = 4;
static final String TABLE = "guestlist";

static final String C_ID = "_id";
static final String C_NAME = "name";
static final String C_SIDE = "side";
static final String C_INVITE = "invite";
static final String C_COUNT = "count";
static final String C_ATTEND = "attend";
static final String C_ALCOHOL = "alcohol";


public DBhelper(Context context) {
    super(context, DATABASE, null, VERSION);
}

public void onCreate(SQLiteDatabase db) {
    db.execSQL("CREATE TABLE " + TABLE + "(" + C_ID
            + " INTEGER PRIMARY KEY AUTOINCREMENT," + C_NAME + " text,"
            + C_SIDE + " text," + C_INVITE + " text," + C_COUNT + " text,"
            + C_ATTEND + " text," + C_ALCOHOL + " text )");
}

public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

    db.execSQL("drop table " + TABLE);

    onCreate(db);
}

Answer 1

试试这个代码：

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <!-- Editext for Search -->
    <EditText android:id="@+id/inputSearch"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:hint="Search products.."
        android:inputType="textVisiblePassword"/>

    <!-- List View -->
    <ListView
        android:id="@+id/list_view"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content" />

</LinearLayout>

list_item.xml

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

    <!-- Single ListItem -->

    <!-- Product Name -->
    <TextView android:id="@+id/product_name"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:padding="10dip"
        android:textSize="16dip"
        android:textStyle="bold"/>    

</LinearLayout>

现在打开您的MainActivity.java并粘贴以下代码以创建一个简单的ListView 。 在下面的代码中，我将所有列表数据存储在一个名为products []的数组中，并使用简单的ArrayAdapter附加到listview 。

MainActivity.java

import java.util.ArrayList;
import java.util.HashMap;

import android.app.Activity;
import android.os.Bundle;
import android.text.Editable;
import android.text.TextWatcher;
import android.widget.ArrayAdapter;
import android.widget.EditText;
import android.widget.ListView;

public class MainActivity extends Activity {

    // List view
    private ListView lv;

    // Listview Adapter
    ArrayAdapter<String> adapter;

    // Search EditText
    EditText inputSearch;


    // ArrayList for Listview
    ArrayList<HashMap<String, String>> productList;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // Listview Data
        String products[] = {"Item1", "Item2", "Item3", "Item4", "Item5",
                                "Item6", "Item7",
                                "Item8", "Item9", "Item10", "Item11"};

        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);       

    }

}

启用搜索功能

可以通过编写简单的代码行来启用搜索功能。 您需要做的就是将addTextChangedListener添加到EditText 。 用户在EditText中输入新数据后，我们需要从中获取文本并将其传递给数组适配器过滤器。 MainActivity.java中的以下所有代码

将此方法添加到MainActivity.java

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) {
        // TODO Auto-generated method stub

    }

    @Override
    public void afterTextChanged(Editable arg0) {
        // TODO Auto-generated method stub                          
    }
});

最后，在您的AndroidManifest.xml文件中添加以下属性，以在加载Activity时隐藏键盘。

android:windowSoftInputMode="stateHidden"