/*
 * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *        http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package net.micode.notes.ui;

import android.content.Context;
import android.database.Cursor;
import android.view.View;
import android.view.ViewGroup;
import android.widget.CursorAdapter;
import android.widget.LinearLayout;
import android.widget.TextView;

import net.micode.notes.R;
import net.micode.notes.data.Notes;
import net.micode.notes.data.Notes.NoteColumns;

/**
 *  FoldersListAdapter 类是一个 CursorAdapter ,用来从 Cursor(数据库查询结果)加载文件夹列表。
 *
 * 主要点:
 *
 * 定义了 PROJECTION 数组,其中包含从数据库读取的列: 笔记ID 和 片段。
 *
 * 定义了投影中列索引的常量:ID_COLUMN 和 NAME_COLUMN。这被用来从 Cursor 获取值。
 *
 * 构造函数调用了父 CursorAdapter 构造函数,传入 Context 和 Cursor。
 *
 * 它可能实现 newView() 和 bindView() 方法来实际实例化列表项视图并将数据绑定到它们。
 *
 * 所以总的来说,这个适配器类:
 *
 * 定义了需要从数据库读取的列
 * 提供了列索引常量
 * 在构造函数中接受 Cursor
 * 在 newView()中创建列表项视图
 * 在bindView()中将数据绑定到这些视图
 */

public class FoldersListAdapter extends CursorAdapter {
    public static final String [] PROJECTION = {
        NoteColumns.ID,
        NoteColumns.SNIPPET
    };

    public static final int ID_COLUMN   = 0;
    public static final int NAME_COLUMN = 1;

    public FoldersListAdapter(Context context, Cursor c) {
        super(context, c);
        // TODO Auto-generated constructor stub
    }

    @Override
    public View newView(Context context, Cursor cursor, ViewGroup parent) {
        return new FolderListItem(context);
    }

    @Override
    public void bindView(View view, Context context, Cursor cursor) {
        if (view instanceof FolderListItem) {
            String folderName = (cursor.getLong(ID_COLUMN) == Notes.ID_ROOT_FOLDER) ? context
                    .getString(R.string.menu_move_parent_folder) : cursor.getString(NAME_COLUMN);
            ((FolderListItem) view).bind(folderName);
        }
    }

    public String getFolderName(Context context, int position) {
        Cursor cursor = (Cursor) getItem(position);
        return (cursor.getLong(ID_COLUMN) == Notes.ID_ROOT_FOLDER) ? context
                .getString(R.string.menu_move_parent_folder) : cursor.getString(NAME_COLUMN);
    }

    private class FolderListItem extends LinearLayout {
        private TextView mName;

        public FolderListItem(Context context) {
            super(context);
            inflate(context, R.layout.folder_list_item, this);
            mName = (TextView) findViewById(R.id.tv_folder_name);
        }

        public void bind(String name) {
            mName.setText(name);
        }
    }

}
