同事负责开发的APP有一个搜索功能，并且需要显示搜索的历史记录，我闲暇之余帮她开发了这个功能，现把该页面抽取成一个demo分享给大家。

实现效果如图所示：

本案例实现起来很简单，所以可以直接拿来嵌入项目中使用，涉及到的知识点：
- 数据库的增删改查操作
- ListView和ScrollView的嵌套冲突解决
- 监听软键盘回车按钮设置为搜索按钮
- 使用TextWatcher( )实时筛选
- 已搜索的关键字再次搜索不重复添加到数据库
- 刚进入页面设置软键盘不因为EditText而自动弹出

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代码

1. RecordSQLiteOpenHelper.java

package com.cwvs.microlife;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);}@Overridepublic void onCreate(SQLiteDatabase db) {db.execSQL("create table records(id integer primary key autoincrement,name varchar(200))");}@Overridepublic void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {}}

1. MainActivity.java

package com.cwvs.microlife;import java.util.Date;import android.app.Activity;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
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.SimpleCursorAdapter;
import android.widget.TextView;
import android.widget.Toast;public class MainActivity extends Activity {private EditText et_search;private TextView tv_tip;private MyListView listView;private TextView tv_clear;private RecordSQLiteOpenHelper helper = new RecordSQLiteOpenHelper(this);;private SQLiteDatabase db;private BaseAdapter adapter;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);requestWindowFeature(Window.FEATURE_NO_TITLE);setContentView(R.layout.activity_main);// 初始化控件initView();// 清空搜索历史tv_clear.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {deleteData();queryData("");}});// 搜索框的键盘搜索键点击回调et_search.setOnKeyListener(new View.OnKeyListener() {// 输入完后按键盘上的搜索键public boolean onKey(View v, int keyCode, KeyEvent event) {if (keyCode == KeyEvent.KEYCODE_ENTER && event.getAction() == KeyEvent.ACTION_DOWN) {// 修改回车键功能// 先隐藏键盘((InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE)).hideSoftInputFromWindow(getCurrentFocus().getWindowToken(), InputMethodManager.HIDE_NOT_ALWAYS);// 按完搜索键后将当前查询的关键字保存起来,如果该关键字已经存在就不执行保存boolean hasData = hasData(et_search.getText().toString().trim());if (!hasData) {insertData(et_search.getText().toString().trim());queryData("");}// TODO 根据输入的内容模糊查询商品，并跳转到另一个界面，由你自己去实现Toast.makeText(MainActivity.this, "clicked!", Toast.LENGTH_SHORT).show();}return false;}});// 搜索框的文本变化实时监听et_search.addTextChangedListener(new TextWatcher() {@Overridepublic void beforeTextChanged(CharSequence s, int start, int count, int after) {}@Overridepublic void onTextChanged(CharSequence s, int start, int before, int count) {}@Overridepublic void afterTextChanged(Editable s) {if (s.toString().trim().length() == 0) {tv_tip.setText("搜索历史");} else {tv_tip.setText("搜索结果");}String tempName = et_search.getText().toString();// 根据tempName去模糊查询数据库中有没有数据queryData(tempName);}});listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {@Overridepublic 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);Toast.makeText(MainActivity.this, name, Toast.LENGTH_SHORT).show();// TODO 获取到item上面的文字，根据该关键字跳转到另一个页面查询，由你自己去实现}});// 插入数据，便于测试，否则第一次进入没有数据怎么测试呀？Date date = new Date();long time = date.getTime();insertData("Leo" + time);// 第一次进入查询所有的历史记录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);// 创建adapter适配器对象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);// 设置适配器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);tv_tip = (TextView) findViewById(R.id.tv_tip);listView = (com.cwvs.microlife.MyListView) findViewById(R.id.listView);tv_clear = (TextView) findViewById(R.id.tv_clear);// 调整EditText左边的搜索按钮的大小Drawable drawable = getResources().getDrawable(R.drawable.search);drawable.setBounds(0, 0, 60, 60);// 第一0是距左边距离，第二0是距上边距离，60分别是长宽et_search.setCompoundDrawables(drawable, null, null, null);// 只放左边}
}

1. MyListView.java

package com.cwvs.microlife;import android.content.Context;
import android.util.AttributeSet;
import android.widget.ListView;public class MyListView extends ListView {public MyListView(Context context) {super(context);}public MyListView(Context context, AttributeSet attrs) {super(context, attrs);}public MyListView(Context context, AttributeSet attrs, int defStyle) {super(context, attrs, defStyle);}@Overrideprotected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {int expandSpec = MeasureSpec.makeMeasureSpec(Integer.MAX_VALUE >> 2,MeasureSpec.AT_MOST);super.onMeasure(widthMeasureSpec, expandSpec);}}

1. activity_main.xml

<LinearLayout 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"android:focusableInTouchMode="true"android:orientation="vertical"tools:context="${relativePackage}.${activityClass}"><LinearLayout
        android:layout_width="fill_parent"android:layout_height="50dp"android:background="#E54141"android:orientation="horizontal"android:paddingRight="16dp"><ImageView
            android:layout_width="45dp"android:layout_height="45dp"android:layout_gravity="center_vertical"android:padding="10dp"android:src="@drawable/back" /><EditText
            android:id="@+id/et_search"android:layout_width="0dp"android:layout_height="match_parent"android:layout_weight="1"android:background="@null"android:drawableLeft="@drawable/search"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"android:textSize="16sp" /></LinearLayout><ScrollView
        android:layout_width="wrap_content"android:layout_height="wrap_content"><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="50dp"android:gravity="left|center_vertical"android:text="搜索历史" /><View
                    android:layout_width="match_parent"android:layout_height="1dp"android:background="#EEEEEE"></View><com.cwvs.microlife.MyListView
                    android:id="@+id/listView"android:layout_width="match_parent"android:layout_height="wrap_content"></com.cwvs.microlife.MyListView></LinearLayout><View
                android:layout_width="match_parent"android:layout_height="1dp"android:background="#EEEEEE"></View><TextView
                android:id="@+id/tv_clear"android:layout_width="match_parent"android:layout_height="40dp"android:background="#F6F6F6"android:gravity="center"android:text="清除搜索历史" /><View
                android:layout_width="match_parent"android:layout_height="1dp"android:layout_marginBottom="20dp"android:background="#EEEEEE"></View></LinearLayout></ScrollView>
</LinearLayout>

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完整案例源代码