最近自己在尝试做app开发，遇到搜索框功能，便查找了一下但是感觉自己想的或许更好理解和记住，便自己思考了一下。废话不多说，下面是实现代码，供大家参考，有待改进。

先说一下我整体思路，因为刚开始写所以相关数据都没有上传服务器过。首先建立一个数据库，将可以搜索的相关内容存储到数据库的搜索表当中，然后在搜索框中获取输入的第一个字符，按照字符搜索相关内容。同时创建历史搜索表，将搜索过的内容放入到搜索历史表当中去。每一次进入搜索页面都从搜索历史表当中获取之前的搜索历史，点击清空搜索历史将删除表中的所有内容。

这是我点击跳转到搜索界面，只需要关注最顶上即可

其中第一步就是自定listview布局，这一块一搬自定义的大多数相同

package com.example.tjtcexample.subsidiary.services1.search;

import android.content.Context;
import android.util.AttributeSet;
import android.widget.ListView;

public class ListViewForScrollView extends ListView {
    public ListViewForScrollView(Context context) {
        super(context);
    }

    public ListViewForScrollView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public ListViewForScrollView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
    }


    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        int expected=MeasureSpec.makeMeasureSpec(Integer.MAX_VALUE>>2,MeasureSpec.AT_MOST);
        super.onMeasure(widthMeasureSpec, expected);
    }
}

然后在xml中建立布局，效果见上图

<?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:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        android:layout_margin="10dp">
        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="horizontal">
            <ImageView
                android:layout_width="0dp"
                android:layout_height="30dp"
                android:layout_weight="1"
                android:background="@drawable/back"
                android:layout_gravity="center"
                android:id="@+id/iv_searchback"/>
            <LinearLayout
                android:layout_width="0dp"
                android:layout_height="wrap_content"
                android:layout_weight="8"
                android:orientation="horizontal"

                android:background="@drawable/search_round"
                android:id="@+id/linear_searchitem">

                <EditText
                    android:id="@+id/et_searchtext"
                    android:layout_width="0dp"
                    android:layout_height="match_parent"
                    android:layout_weight="3"
                    android:hint="输入关键字搜索"
                    android:background="@null"
                    android:textSize="18sp"
                    android:drawableLeft="@android:drawable/ic_menu_search"
                    android:singleLine="true"
                    android:imeOptions="actionSearch"
                    />
                <Button
                    android:id="@+id/btn_search"
                    android:layout_width="0dp"
                    android:layout_height="match_parent"
                    android:layout_weight="1"
                    android:text="搜索"
                    android:textSize="18sp"
                    android:background="@drawable/btn_round"/>
            </LinearLayout>
        </LinearLayout>

        <com.example.tjtcexample.subsidiary.services1.search.ListViewForScrollView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:id="@+id/search_listview"/>
    </LinearLayout>

    <ScrollView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_margin="10dp">
        <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">
                <TextView
                    android:layout_width="match_parent"
                    android:layout_height="45dp"
                    android:text="搜索历史"
                    android:textSize="18sp"
                    android:layout_gravity="center"
                    android:gravity="center"/>
              <TextView
                  android:layout_width="match_parent"
                  android:layout_height="match_parent"
                  android:id="@+id/tv_searchhistory"
                  android:background="@color/teal_200"/>
            </LinearLayout>
            <View
                android:layout_width="match_parent"
                android:layout_height="2dp"
                android:background="@color/gray"/>
            <TextView
                android:id="@+id/tv_clearsearch"
                android:layout_width="match_parent"
                android:layout_height="45dp"
                android:text="清空搜索历史"
                android:textSize="18sp"
                android:layout_gravity="center"
                android:gravity="center"/>
        </LinearLayout>
    </ScrollView>
</LinearLayout>

public class SearchActivity extends AppCompatActivity {

    private ImageView iv_searchBack;
    private Button btn_search;
    private EditText et_searchText;
    private ListViewForScrollView listViewForScrollView;
    private TextView tv_historyText,tv_clearHistory;
    private List<String> searchList=new ArrayList<>();
    private int count=0;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_search);
        initView();
        setListeners();
    }

    /**
     * 获取相对应的控件
     */
    private void initView() {
        iv_searchBack=findViewById(R.id.iv_searchback);
        btn_search=findViewById(R.id.btn_search);
        et_searchText=findViewById(R.id.et_searchtext);
        listViewForScrollView=findViewById(R.id.search_listview);
        tv_historyText=findViewById(R.id.tv_searchhistory);
        tv_clearHistory=findViewById(R.id.tv_clearsearch);
    }

    /**
     * 实现搜索功能
     */
    private void setListeners() {

        /**
         * 存放搜索历史的表
         */
        SQLiteOpenHelper helper=SearchSQLiteOpenHelper.getmInstance(SearchActivity.this);

        /**
         * 返回服务页面
         */
        iv_searchBack.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent=new Intent(SearchActivity.this, Services1Activity.class);
                startActivity(intent);
            }
        });

        /**
         * 给搜索历史传入空
         */
        tv_historyText.setText(" ");

        /**
         * 搜索按钮的监听
         */
        btn_search.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                String obtain=et_searchText.getText().toString().trim();
                /**
                 * 下一次点击搜索按钮时清空前一次搜索列表
                 */
                count++;
                if(count%1==0){
                    searchList.clear();
                }
                /**
                 * 将搜索框内容放入到搜索历史当中去
                 */
                tv_historyText.append(obtain+" ");
                /**
                 * 将搜索框内容放入到搜索历史表当中去
                 */
                SQLiteDatabase db_history=helper.getWritableDatabase();
                if(db_history.isOpen()){
                    String add_historysearchname_sql="insert into historysearch(historyname) values(?);";
                    db_history.execSQL(add_historysearchname_sql,new Object[]{obtain});
                    Toast.makeText(SearchActivity.this,"增加成功",Toast.LENGTH_SHORT).show();
                }
                db_history.close();

                /**
                 * 判断搜索框是否为空
                 */
                if(obtain.isEmpty()){
                    Toast.makeText(SearchActivity.this,"搜索框为空",Toast.LENGTH_SHORT).show();
                    searchList.clear();
                }else{
                    /**
                     * 获取数据库中的表，取出搜索框中的首字符放入查询语句进行查询相匹配的内容
                     */
                    SQLiteDatabase db_search=helper.getReadableDatabase();
                    if(db_search.isOpen()){
                        String firstChar=obtain.substring(0,1);
                        String query_sql="select * from search where searchname like '"+firstChar+"%'";
                        Cursor cursor = db_search.rawQuery(query_sql,null);
                        if(cursor.getCount()==0){
                            Toast.makeText(SearchActivity.this,"没有该服务",Toast.LENGTH_SHORT).show();
                        }else{
                            cursor.moveToFirst();
                            String searchname=cursor.getString(cursor.getColumnIndex("searchname"));
                            searchList.add(searchname);
                        }
                        while(cursor.moveToNext()){
                            String searchname1=cursor.getString(cursor.getColumnIndex("searchname"));
                            searchList.add(searchname1);
                        }
                        cursor.close();
                    }
                    db_search.close();
                }
                /**
                 * 自定义搜索适配器，将适配器放入自定义的listview当中
                 */
                SearchBaseAdapter searchBaseAdapter=new SearchBaseAdapter();
                listViewForScrollView.setAdapter(searchBaseAdapter);

            }
        });
    /**
         * 搜索列表的点击事件
         */
        listViewForScrollView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                Toast.makeText(SearchActivity.this,"点击"+searchList.get(position),Toast.LENGTH_SHORT).show();

            }
        });


        SQLiteDatabase db_get_history=helper.getReadableDatabase();
        if(db_get_history.isOpen()){
            String sql_history_query="select * from historysearch;";
            Cursor cursor = db_get_history.rawQuery(sql_history_query, null);
            if(cursor.getCount()==0){
                Toast.makeText(SearchActivity.this,"没有搜索历史",Toast.LENGTH_SHORT).show();
            }else{
                cursor.moveToFirst();
                String history_name=cursor.getString(cursor.getColumnIndex("historyname"));
                tv_historyText.append(history_name+" ");
            }
            while (cursor.moveToNext()){
                String history_name=cursor.getString(cursor.getColumnIndex("historyname"));
                tv_historyText.append(history_name+" ");
            }
            cursor.close();
        }
        db_get_history.close();



        tv_clearHistory.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                SQLiteDatabase db_delete_history=helper.getWritableDatabase();
                if(db_delete_history.isOpen()){
                    String sql_delete_history="delete  from historysearch;";
                    db_delete_history.execSQL(sql_delete_history);
                    Toast.makeText(SearchActivity.this,"删除成功",Toast.LENGTH_SHORT).show();
                }
                tv_historyText.setText(" ");
            }
        });
    }

    /**
     * 适配器获取数据库中搜索表所存放的内容
     */
    class SearchBaseAdapter extends BaseAdapter{

        @Override
        public int getCount() {
            return searchList.size();
        }

        @Override
        public Object getItem(int position) {
            return searchList.get(position);
        }

        @Override
        public long getItemId(int position) {
            return position;
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            ViewHolder holder=null;
            if(convertView==null){
                convertView=View.inflate(SearchActivity.this,R.layout.searchlist_item,null);
                holder=new ViewHolder();
                holder.tv_searchLisItem=convertView.findViewById(R.id.tv_searchlistitem);
                convertView.setTag(holder);
            }else{
                holder=(ViewHolder)convertView.getTag();
            }
            holder.tv_searchLisItem.setText(searchList.get(position));
            return convertView;
        }
    }
    class ViewHolder{
        TextView tv_searchLisItem;
    }
}

下面这就是建库建表的了

public class SearchSQLiteOpenHelper extends SQLiteOpenHelper {

    private static SQLiteOpenHelper mInstance=null;
    public static synchronized SQLiteOpenHelper getmInstance(Context context){
        if(mInstance==null){
            mInstance=new SearchSQLiteOpenHelper(context,"searchitem.db",null,3);
        }
        return mInstance;
    }
    public SearchSQLiteOpenHelper(@Nullable Context context, @Nullable String name, @Nullable SQLiteDatabase.CursorFactory factory, int version) {
        super(context, name, factory, version);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        String sql="create table search(_id integer primary key autoincrement,searchname varchar(20));";
        db.execSQL(sql);
        String sql_history="create table historysearch(_id integer primary key autoincrement,historyname varchar(20));";
        db.execSQL(sql_history);
    }

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

    }
}

如果帮助到你，哈哈哈哈