Android AutoCompleteTextView连接数据库自动提示的方法(附demo源码下载)

2020-04-11 10:48:45

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本文实例讲述了Android AutoCompleteTextView连接数据库自动提示的方法。分享给大家供大家参考，具体如下：

这个简单例子也体现MVC的思想。AutoCompleteTextView 就是View，而SimpleCursorAdapter就是Controller，SQLiteOpenHelper就相当于Model。

1、首先定义MVC中的Model，自定义DBHelper类继承SQLiteOpenHelper用于访问数据库

import android.content.Context;import android.database.Cursor;import android.database.sqlite.SQLiteDatabase;import android.database.sqlite.SQLiteOpenHelper;/** * * @author lai_zs * @date：2012-2-16 下午4:16:02 */public class DBHelper extends SQLiteOpenHelper {  private static final int DATABASE_VERSION = 1;  private static final String DATABASE_NAME = "autoComplete.db";  // 根据name自动查询  public static final String NAME = "name";  public DBHelper(Context context) {    super(context, DATABASE_NAME, null, DATABASE_VERSION);  }  @Override  public void onCreate(SQLiteDatabase db) {    String sqlString = "createtable test (_id integer primary key autoincrement,name varchat(20) not null onconflict fail)";    db.execSQL(sqlString);    // 初始数据库表    String[] nameStrArrayStr = new String[] { "aaa", "abc", "cde", "中国", "美女", "提示" };    for (int i = 0; i < nameStrArrayStr.length; i++) {      db.execSQL("INSERT INTOtest(" + NAME + ")values(?)",new Object[] { nameStrArrayStr[i] });    }  }  @Override  public void onUpgrade(SQLiteDatabase arg0, int arg1, int arg2) {    // do nothing here  }  /**   * 根据输入内容模糊查询   * @param name   * @return   */  public Cursor query(String name) {    SQLiteDatabase db = this.getReadableDatabase();    return db.rawQuery("select* from test where name like '%" + name + "%' limit 10",null);  }}

2、定义AutoCompleteAdater继承SimpleCursorAdapter控制数据交互

import android.content.Context;import android.database.Cursor;import android.widget.SimpleCursorAdapter;/** * * @author lai_zs * @date：2012-2-16 下午3:49:25 */public class AutoCompleteAdater extends SimpleCursorAdapter {  private DBHelper dbHelper = null;  private Context context;  // 查询字段  private String queryField;  public AutoCompleteAdater(Context context, int layout, Cursor c,String from, int to) {    super(context, layout, c, new String[] { from },new int[] { to });    this.context = context;    this.queryField = from;  }  /**   * 动态查询数据库   */  @Override  public Cursor runQueryOnBackgroundThread(CharSequenceconstraint) {    if (constraint != null) {      return getDbHelper().query((String) constraint);    } else {      return null;    }  }  /**   * 这里设置在弹出的提示列表中点击某一项后的返回值,返回值将被显示在文本框中   */  @Override  public CharSequence convertToString(Cursor cursor) {    return cursor.getString(cursor.getColumnIndex(queryField));  }  public DBHelper getDbHelper() {    if (dbHelper == null) {      dbHelper = new DBHelper(this.context);    }    return dbHelper;  }}

3、最后定义View

<AutoCompleteTextView    android:id="@+id/autoCompleteTextView1"    android:layout_width="match_parent"    android:layout_height="wrap_content"    android:text=""    android:hint="@string/dbAutoComlete" >    <requestFocus /></AutoCompleteTextView>

4、在Activity中关联View和Adapter

@Overridepublic void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.main);    AutoCompleteAdatercursorAdapter = new AutoCompleteAdater(this, android.R.layout.simple_dropdown_item_1line,null, DBHelper.NAME, android.R.id.text1);    // 设置输入一个字符就弹出提示列表(默认输入两个字符时才弹出提示)    ((AutoCompleteTextView) this.findViewById(R.id.autoCompleteTextView1)).setThreshold(1);    ((AutoCompleteTextView) this.findViewById(R.id.autoCompleteTextView1)).setAdapter(cursorAdapter);}