Android开发之实现搜索框搜索
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
android:orientation="vertical" android:layout_width="match_parent" android:layout_height="match_parent"> android:layout_width="match_parent" android:layout_height="wrap_content" android:orientation="vertical" android:layout_margin="10dp"> android:layout_width="match_parent" android:layout_height="wrap_content" android:orientation="horizontal"> 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"/> 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"> 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" /> 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"/>
android:layout_width="match_parent" android:layout_height="wrap_content" android:id="@+id/search_listview"/> android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_margin="10dp"> android:layout_width="match_parent" android:layout_height="wrap_content" android:orientation="vertical"> android:layout_width="match_parent" android:layout_height="wrap_content" android:orientation="vertical"> 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"/> android:layout_width="match_parent" android:layout_height="match_parent" android:id="@+id/tv_searchhistory" android:background="@color/teal_200"/> android:layout_width="match_parent" android:layout_height="2dp" android:background="@color/gray"/> 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"/> 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 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