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

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();        }    }}

 

 

↳
	↳
		↳
			↳	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。