Android搜索功能

项目中的一个页面需要实现搜索查询功能，并且需求要在EditText下面显示历史查询记录和清除查询记录。网上逛了一圈，然后看到一篇不错的帖子，原创：http://blog.csdn.net/LeoLeoHan/article/details/50688283?locationNum=4&fps=1#comments
先设置软键盘右下角显示搜索，xml中设置俩个属性即可：

android:imeOptions="actionSearch"android:singleLine="true"

然后设置软键盘搜索监听:

search.setOnKeyListener(new View.OnKeyListener() {            @Override            public boolean onKey(View v, int keyCode, KeyEvent event) {                if (keyCode == KeyEvent.KEYCODE_ENTER && event.getAction() == KeyEvent.ACTION_DOWN) {                    // 先隐藏键盘                    ((InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE)).hideSoftInputFromWindow(getCurrentFocus().getWindowToken(), InputMethodManager.HIDE_NOT_ALWAYS);                    Toast.makeText(MainActivity.this,"搜索",Toast.LENGTH_SHORT).show();                }                return false;            }        });

完整代码如下：
xml代码：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical">    <LinearLayout        android:layout_width="match_parent"        android:layout_height="50dp"        android:orientation="horizontal"        android:background="#cccccc">        <ImageView            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:layout_gravity="center_vertical"            android:padding="10dp"            android:src="@drawable/back" />        <EditText            android:id="@+id/et_search"            android:layout_width="260dp"            android:layout_height="match_parent"            android:background="@null"            android:drawablePadding="8dp"            android:gravity="start|center_vertical"            android:hint="输入查询的关键字"            android:imeOptions="actionSearch"            android:singleLine="true"            android:textColor="@android:color/white"/>        <TextView            android:id="@+id/check"            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:text="查询"            android:textSize="16sp"/>    </LinearLayout>    <LinearLayout        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:orientation="vertical">        <LinearLayout            android:layout_width="match_parent"            android:layout_height="wrap_content"            android:orientation="vertical"            android:paddingLeft="20dp">            <TextView                android:id="@+id/tv_tip"                android:layout_width="match_parent"                android:layout_height="wrap_content"                android:padding="10dp"                android:text="搜索历史" />            <View                android:layout_width="match_parent"                android:layout_height="1dp"                android:background="#EEEEEE"/>            <ListView                android:id="@+id/listView"                android:layout_width="match_parent"                android:layout_height="wrap_content"/>        </LinearLayout>        <TextView            android:id="@+id/clear_history"            android:layout_width="match_parent"            android:layout_height="40dp"            android:background="#EEEEEE"            android:gravity="center"            android:text="清除搜索历史" />    </LinearLayout></LinearLayout>

RecordSQLiteOpenHelper：

package com.example.lenovo.demo;import android.content.Context;import android.database.sqlite.SQLiteDatabase;import android.database.sqlite.SQLiteOpenHelper;public class RecordSQLiteOpenHelper extends SQLiteOpenHelper {    private static String name = "temp.db";    private static Integer version = 1;    public RecordSQLiteOpenHelper(Context context) {        super(context, name, null, version);    }    @Override    public void onCreate(SQLiteDatabase db) {        db.execSQL("create table records(id integer primary key autoincrement,name varchar(200))");    }    @Override    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {    }}

MainActivity代码：

package com.example.lenovo.demo;import android.app.Activity;import android.content.Context;import android.database.Cursor;import android.database.sqlite.SQLiteDatabase;import android.os.Bundle;import android.os.Handler;import android.text.Editable;import android.text.TextWatcher;import android.view.KeyEvent;import android.view.View;import android.view.Window;import android.view.inputmethod.InputMethodManager;import android.widget.AdapterView;import android.widget.BaseAdapter;import android.widget.CursorAdapter;import android.widget.EditText;import android.widget.ListView;import android.widget.SimpleCursorAdapter;import android.widget.TextView;public class MainActivity extends Activity {    private EditText et_search;    private ListView listView;    private TextView clear_history;    private RecordSQLiteOpenHelper helper = new RecordSQLiteOpenHelper(this);    private SQLiteDatabase db;    private BaseAdapter adapter;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        requestWindowFeature(Window.FEATURE_NO_TITLE);        setContentView(R.layout.activity_main);        initView();        clear_history.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View v) {                deleteData();                queryData("");            }        });        et_search.setOnKeyListener(new View.OnKeyListener() {            public boolean onKey(View v, int keyCode, KeyEvent event) {                if (keyCode == KeyEvent.KEYCODE_ENTER && event.getAction() == KeyEvent.ACTION_DOWN) {                    // 先隐藏键盘                    ((InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE)).hideSoftInputFromWindow(getCurrentFocus().getWindowToken(), InputMethodManager.HIDE_NOT_ALWAYS);                    //判断关键字是否已经保存，如果已经保存，就不需要再保存了                    checkRecord();                    //这里执行逻辑，跳转到另一个页面                }                return false;            }        });        et_search.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) {            }            @Override            public void afterTextChanged(Editable s) {                final String tempName = et_search.getText().toString();                // 500ms后再根据tempName去模糊查询数据库中有没有数据，防止用户频繁改变输入的内容                new Handler().postDelayed(new Runnable() {                    @Override                    public void run() {                        queryData(tempName);                    }                },500);            }        });        listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {            @Override            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {                TextView textView = (TextView) view.findViewById(android.R.id.text1);                String name = textView.getText().toString();                et_search.setText(name);                //这里根据选中的item执行逻辑，跳转到另一个页面            }        });        queryData("");    }    /**     * 插入数据     */    private void insertData(String tempName) {        db = helper.getWritableDatabase();        db.execSQL("insert into records(name) values('" + tempName + "')");        db.close();    }    /**     * 模糊查询数据     */    private void queryData(String tempName) {        Cursor cursor = helper.getReadableDatabase().rawQuery("select id as _id,name from records where name like '%" + tempName + "%' order by id desc ", null);        adapter = new SimpleCursorAdapter(this, android.R.layout.simple_list_item_1, cursor, new String[] { "name" },                new int[] { android.R.id.text1 }, CursorAdapter.FLAG_REGISTER_CONTENT_OBSERVER);        listView.setAdapter(adapter);        adapter.notifyDataSetChanged();    }    /**     * 检查数据库中是否已经有该条记录     */    private boolean hasData(String tempName) {        Cursor cursor = helper.getReadableDatabase().rawQuery("select id as _id,name from records where name =?", new String[]{tempName});        //判断是否有下一个        return cursor.moveToNext();    }    /**     * 清空数据     */    private void deleteData() {        db = helper.getWritableDatabase();        db.execSQL("delete from records");        db.close();    }    private void initView() {        et_search = (EditText) findViewById(R.id.et_search);        listView = (ListView) findViewById(R.id.listView);        clear_history = (TextView) findViewById(R.id.clear_history);        findViewById(R.id.check).setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View v) {                checkRecord();                //这里执行逻辑，跳转到另一个页面            }        });    }    public void checkRecord(){        boolean hasData = hasData(et_search.getText().toString().trim());        if (!hasData) {            insertData(et_search.getText().toString().trim());            queryData("");        }    }}