AutoCompleteTextView 与sqlite绑定实现记住用户输入的内容并自动提示

把用户输入的内容保存到数据库表中，然后用户输入时，进行模糊查询并把查询结果附到AutoCompleteTextView中。

1：activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"  

    xmlns:tools="http://schemas.android.com/tools"  

    android:layout_width="fill_parent"  

    android:layout_height="fill_parent"  

    android:orientation="vertical" >  

      

    <AutoCompleteTextView  

            android:id="@+id/actValue"  

            android:layout_width="match_parent"  

            android:layout_height="wrap_content" 

            android:completionThreshold="1"

            android:singleLine="true"/>        

            

    <Button 

        android:id="@+id/btnClick"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:text="Click"/>

  

      

</LinearLayout>  

2：DbUtil.java

package com.example.autotest;



import android.content.Context;

import android.database.sqlite.SQLiteDatabase;

import android.database.sqlite.SQLiteOpenHelper;



public class DbUtil extends SQLiteOpenHelper {

    private static final int DATABASE_VERSION = 10;        //当前数据库版本

    private static final String DATABASE_NAME = "wzh.db";

    

    private static final String TABLE_AUTO = "auto";    //国税邮件表

    

    private static final String CREATE_TABLE_AUTO_SQL = "create table " +

            TABLE_AUTO + "( _id integer primary key autoincrement, "+

                          " value varchar)";

    

    

    public DbUtil(Context context) {

        super(context, DATABASE_NAME, null, DATABASE_VERSION);

    }

    

    /*

     * 数据库第一次被创建时调用onCreate

     */

    @Override

    public void onCreate(SQLiteDatabase db) {

        db.execSQL(CREATE_TABLE_AUTO_SQL);

    }

    

    /*

     * 如果 DATABASE_VERSION 改变 系统会调用onUpgrade

     */

    @Override

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

        db.execSQL("drop table if exists " + TABLE_AUTO);



        onCreate(db);

    }

}

3:DBManager.java

package com.example.autotest;



import android.content.Context;

import android.database.Cursor;

import android.database.sqlite.SQLiteDatabase;



public class DBManager {

    private DbUtil dbUtil = null;

    private SQLiteDatabase db = null;

    

    public DBManager(Context context){

        dbUtil = new DbUtil(context);

        db = dbUtil.getWritableDatabase();

    }

    

    public boolean valueExist(String value){

        int count = 0;

        Cursor c = db.rawQuery("select _id from auto where value = ?", 

                    new String[]{value});

        if(c.moveToNext()){

            count = c.getInt(c.getColumnIndex("_id"));

        }

        c.close();

        return count>0?true:false;

    }

    

    public void addAutoValue(String value){

        if(value!=null && value.length()>0){

            db.beginTransaction();

            try{

                String sql = "insert into auto(_id,value) values(null,?)";

                db.execSQL(sql, new Object[]{value});

                db.setTransactionSuccessful();

            }finally{

                db.endTransaction();

            }

        }

    }

    

    public Cursor selectAutoValues(String value){

        String sql = "select _id,value from auto where value like ? limit 10";

        Cursor c = db.rawQuery(sql, new String[]{"%"+value+"%"});

        return c;

    }

    

    



    /**

     * 关闭数据连接资源

     */

    public void dbClose(){

        if(null != db){

            db.close();

        }    

    }

}

4:AutoCompleteAdater.java

package com.example.autotest;



import android.content.Context;

import android.database.Cursor;

import android.widget.SimpleCursorAdapter;



public class AutoCompleteAdater extends SimpleCursorAdapter{

    private DBManager dbManager = null;

    private Context context;



    // 查询字段

    private String value;

    

    @SuppressWarnings("deprecation")

    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.value = from;

    }

    

    /**

     * 动态查询数据库

     */

    @Override

    public Cursor runQueryOnBackgroundThread(CharSequence constraint) {

       if (constraint != null) {

           return getDbManager().selectAutoValues((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(value));

    }

    

    

    public DBManager getDbManager(){

        return dbManager==null?new DBManager(this.context):dbManager;

    }

}

5:MainActivity.java

package com.example.autotest;



import android.os.Bundle;

import android.app.Activity;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.AutoCompleteTextView;

import android.widget.Button;



public class MainActivity extends Activity {

    private AutoCompleteTextView actValue = null;

    private Button btnClick = null;

    private DBManager dbManager = null;

    

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        

        actValue = (AutoCompleteTextView) findViewById(R.id.actValue);

        btnClick = (Button)findViewById(R.id.btnClick);



        

        AutoCompleteAdater cursorAdapter = new AutoCompleteAdater(

                this,

                android.R.layout.simple_dropdown_item_1line,

                null,

                "value",

                android.R.id.text1

            );

        actValue.setAdapter(cursorAdapter);

        

        dbManager = new DBManager(this);

        

        btnClick.setOnClickListener(new OnClickListener(){

            @Override

            public void onClick(View arg0) {

                String value = actValue.getText().toString();

                dbManager.addAutoValue(value);

            }

        });

    }



    @Override

    protected void onDestroy() {

        super.onDestroy();

        if(dbManager!=null){

            dbManager.dbClose();

        }

    }

}

 

 

java.lang.Object
↳	android.view.View
	↳	android.widget.TextView
		↳	android.widget.EditText
			↳	android.widget.AutoCompleteTextView

　　可以看出AutoCompleteTextView继承自EditText，所以它实际上也是一个文本编辑框，只是多了一个自动提示补全功能，EditText的所有功能AutoCompleteTextView都能实现，其对EditTextAPI进行了丰富。