Android搜索功能的案例，本地保存搜索歷史記錄。
來自： http://blog.csdn.net/leoleohan/article/details/50688283
同事負責開發的APP有一個搜索功能，并且需要顯示搜索的歷史記錄，我閑暇之余幫她開發了這個功能，現把該頁面抽取成一個demo分享給大家。
實現效果如圖所示：
本案例實現起來很簡單，所以可以直接拿來嵌入項目中使用，涉及到的知識點：
- 數據庫的增刪改查操作
- ListView和ScrollView的嵌套沖突解決
- 監聽軟鍵盤回車按鈕設置為搜索按鈕
- 使用TextWatcher( )實時篩選
- 已搜索的關鍵字再次搜索不重復添加到數據庫
- 剛進入頁面設置軟鍵盤不因為EditText而自動彈出
代碼
- 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) { }}</pre>
- MainActivity.java
</ol>
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(); // 清空搜索歷史 tv_clear.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { deleteData(); queryData(""); } }); // 搜索框的鍵盤搜索鍵點擊回調 et_search.setOnKeyListener(new View.OnKeyListener() {// 輸入完后按鍵盤上的搜索鍵 public boolean onKey(View v, int keyCode, KeyEvent event) { if (keyCode == KeyEvent.KEYCODE_ENTER && event.getAction() == KeyEvent.ACTION_DOWN) {// 修改回車鍵功能 // 先隱藏鍵盤 ((InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE)).hideSoftInputFromWindow( getCurrentFocus().getWindowToken(), InputMethodManager.HIDE_NOT_ALWAYS); // 按完搜索鍵后將當前查詢的關鍵字保存起來,如果該關鍵字已經存在就不執行保存 boolean hasData = hasData(et_search.getText().toString().trim()); if (!hasData) { insertData(et_search.getText().toString().trim()); queryData(""); } // TODO 根據輸入的內容模糊查詢商品，并跳轉到另一個界面，由你自己去實現 Toast.makeText(MainActivity.this, "clicked!", Toast.LENGTH_SHORT).show(); } return false; } }); // 搜索框的文本變化實時監聽 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("搜索歷史"); } else { tv_tip.setText("搜索結果"); } String tempName = et_search.getText().toString(); // 根據tempName去模糊查詢數據庫中有沒有數據 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 獲取到item上面的文字，根據該關鍵字跳轉到另一個頁面查詢，由你自己去實現 } }); // 插入數據，便于測試，否則第一次進入沒有數據怎么測試呀？ Date date = new Date(); long time = date.getTime(); insertData("Leo" + time); // 第一次進入查詢所有的歷史記錄 queryData(""); } /** * 插入數據 */ private void insertData(String tempName) { db = helper.getWritableDatabase(); db.execSQL("insert into records(name) values('" + tempName + "')"); db.close(); } /** * 模糊查詢數據 */ 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); // 創建adapter適配器對象 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); // 設置適配器 listView.setAdapter(adapter); adapter.notifyDataSetChanged(); } /** * 檢查數據庫中是否已經有該條記錄 */ private boolean hasData(String tempName) { Cursor cursor = helper.getReadableDatabase().rawQuery( "select id as _id,name from records where name =?", new String[]{tempName}); //判斷是否有下一個 return cursor.moveToNext(); } /** * 清空數據 */ 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); // 調整EditText左邊的搜索按鈕的大小 Drawable drawable = getResources().getDrawable(R.drawable.search); drawable.setBounds(0, 0, 60, 60);// 第一0是距左邊距離，第二0是距上邊距離，60分別是長寬 et_search.setCompoundDrawables(drawable, null, null, null);// 只放左邊 }}</pre>
- MyListView.java
</ol>
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); }}</pre>