如何把你的AutoCompleteTextView连接到数据库
AutoCompleteTextView可以根据输入的文字来显示提示, 它的Adapter可以是一个list, 也可以动态的提取数据库数据.
写了一个例子来展示, 建立一个数据库来储存人名, 只要在AutoCompleteTextView里面输入2个字母就会显示匹配下拉单.
这是一个定制的CursorAdapter, newView会返回一个包含cursor里文字的view, bindView把cursor的数据绑定在view里, convertToString会把view的数据转换为AutoCompleteTextView显示的文字, runQueryOnBackgroundThread方法会查询数据库.private class MyCursorAdpter extends CursorAdapter {
private int columnIndex;
public MyCursorAdpter(Context context, Cursor c, int col) {
super(context, c);
this.columnIndex = col;
}
@Override
public View newView(Context context, Cursor cursor, ViewGroup parent) {
final LayoutInflater inflater = LayoutInflater.from(context);
final TextView view = (TextView) inflater.inflate(
android.R.layout.simple_dropdown_item_1line, parent, false);
view.setText(cursor.getString(columnIndex));
return view;
}
@Override
public void bindView(View view, Context context, Cursor cursor) {
((TextView) view).setText(cursor.getString(columnIndex));
}
@Override
public String convertToString(Cursor cursor) {
return cursor.getString(columnIndex);
}
@Override
public Cursor runQueryOnBackgroundThread(CharSequence constraint) {
if (constraint != null) {
String selection = "name like \'" + constraint.toString() +"%\'";
return sqlite.query("test", columns, selection, null, null, null, null);
}
else {
return null;
}
}
}
复制代码建立数据库, 以及添加数据, 使用CursorAdapter的数据库必须包含_id项. private void createDatas() {
String createTable = "create table test (name varchar(255), _id varchar(255))";
sqlite.execSQL(createTable);
ContentValues values = new ContentValues();
values.put("name", "nicole");
values.put("_id", "0");
sqlite.insert("test", null, values);
values.put("name", "nicolas");
values.put("_id", "1");
sqlite.insert("test", null, values);
values.put("name", "jean");
values.put("_id", "2");
sqlite.insert("test", null, values);
values.put("name", "jennyfer");
values.put("_id", "3");
sqlite.insert("test", null, values);
}