Android搜索功能的案例，本地保存搜索历史记录。

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

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);      }        @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) {        }      }

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;        @Override      protected 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() {              @Override              public 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() {              @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) {                  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() {              @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);                  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);      }        @Override      protected 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="fill_parent" android:layout_weight="264" 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>

完整案例点击下载