倒数第三个-----ui

NotesListAdapter.java

@@ -0,0 +1,232 @@
+/*
+ * 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.util.Log;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.CursorAdapter;
+
+import net.micode.notes.data.Notes;
+
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Iterator;
+
+/*
+直译为便签表连接器，继承了CursorAdapter，它为cursor和ListView提供了连接的桥梁，
+所以NotesListAdapter实现的是鼠标和编辑便签链接的桥梁。
+*/
+public class NotesListAdapter extends CursorAdapter {
+    private static final String TAG = "NotesListAdapter";
+    private Context mContext;
+    private HashMap<Integer, Boolean> mSelectedIndex;
+    private int mNotesCount;//便签数
+    private boolean mChoiceMode;//选择模式标记
+/*
+桌面widget的属性，包括编号和类型
+*/
+    public static class AppWidgetAttribute {
+        public int widgetId;
+        public int widgetType;
+    };
+/*
+函数功能：初始化便签链接器（根据传进来的内容设置相关变量）
+*/
+    public NotesListAdapter(Context context) {
+        super(context, null);//父类对象置空
+        mSelectedIndex = new HashMap<Integer, Boolean>();//新建选项下标的hash表
+        mContext = context;
+        mNotesCount = 0;
+    }
+
+    @Override
+/*
+函数功能：新建一个视图来存储光标所指向的数据（使用兄弟类NotesListItem新建一个项目选项）
+*/
+    public View newView(Context context, Cursor cursor, ViewGroup parent) {
+        return new NotesListItem(context);
+    }
+/*
+函数功能：将已经存在的视图和鼠标指向的数据进行捆绑
+*/
+    @Override
+    public void bindView(View view, Context context, Cursor cursor) {
+        if (view instanceof NotesListItem) {//若view是NotesListItem的一个实例
+            NoteItemData itemData = new NoteItemData(context, cursor);
+            ((NotesListItem) view).bind(context, itemData, mChoiceMode,
+                    isSelectedItem(cursor.getPosition()));
+//则新建一个项目选项并且用bind跟将view和鼠标、内容、便签数据捆绑在一起
+        }
+    }
+/*
+函数功能：设置勾选框
+*/
+    public void setCheckedItem(final int position, final boolean checked) {
+        mSelectedIndex.put(position, checked);//根据定位和是否勾选设置下标
+        notifyDataSetChanged();//在修改后刷新activity
+    }
+/*
+函数功能：判断单选按钮是否勾选
+*/
+    public boolean isInChoiceMode() {
+        return mChoiceMode;
+    }
+/*
+函数功能：设置单项选项框（重置下标并且根据参数mode设置选项）
+*/
+    public void setChoiceMode(boolean mode) {
+        mSelectedIndex.clear();
+        mChoiceMode = mode;
+    }
+/*
+函数功能：选择全部选项
+*/
+    public void selectAll(boolean checked) {
+        Cursor cursor = getCursor();//获取光标位置
+        for (int i = 0; i < getCount(); i++) {
+            if (cursor.moveToPosition(i)) {
+                if (NoteItemData.getNoteType(cursor) == Notes.TYPE_NOTE) {
+                    setCheckedItem(i, checked);
+                }
+            }
+        }
+//遍历所有光标可用的位置在判断为便签类型之后勾选单项框
+    }
+/*
+建立选择项的下标列表
+*/
+    public HashSet<Long> getSelectedItemIds() {
+        HashSet<Long> itemSet = new HashSet<Long>();//建立hash表
+        for (Integer position : mSelectedIndex.keySet()) {//遍历所有的关键
+            if (mSelectedIndex.get(position) == true) {//若光标位置可用
+                Long id = getItemId(position);
+                if (id == Notes.ID_ROOT_FOLDER) {
+                    Log.d(TAG, "Wrong item id, should not happen");//原文件不需要添加
+                } else {
+                    itemSet.add(id);
+                }
+//则将id下标加入选项集合中
+            }
+        }
+
+        return itemSet;
+    }
+/*
+函数功能：建立桌面widget的选项表
+*/
+    public HashSet<AppWidgetAttribute> getSelectedWidget() {
+        HashSet<AppWidgetAttribute> itemSet = new HashSet<AppWidgetAttribute>();
+        for (Integer position : mSelectedIndex.keySet()) {
+            if (mSelectedIndex.get(position) == true) {
+                Cursor c = (Cursor) getItem(position);
+//以上4句和getSelectedItemIds一样
+                if (c != null) {//若光标位置可用就建立新的widget属性并编辑下表和类型，最后添加到选项集中
+                    AppWidgetAttribute widget = new AppWidgetAttribute();
+                    NoteItemData item = new NoteItemData(mContext, c);
+                    widget.widgetId = item.getWidgetId();
+                    widget.widgetType = item.getWidgetType();
+                    itemSet.add(widget);
+                    /**
+                     * Don't close cursor here, only the adapter could close it
+                     */
+                } else {
+                    Log.e(TAG, "Invalid cursor");
+                    return null;
+                }
+            }
+        }
+        return itemSet;
+    }
+/*
+函数功能：获取选项个数
+*/
+    public int getSelectedCount() {
+        Collection<Boolean> values = mSelectedIndex.values();//首先获取选项下标的值
+        if (null == values) {
+            return 0;
+        }
+        Iterator<Boolean> iter = values.iterator();//初始化叠加器
+        int count = 0;
+        while (iter.hasNext()) {
+            if (true == iter.next()) {
+//若value值为真，计数+1
+                count++;
+            }
+        }
+        return count;
+    }
+/*
+函数功能：判断是否全部选中
+*/
+    public boolean isAllSelected() {
+        int checkedCount = getSelectedCount();
+        return (checkedCount != 0 && checkedCount == mNotesCount);
+//获取选项数看是否等于便签的个数
+    }
+/*
+函数功能：判断是否为选项表（通过传递的下标来确定）
+*/
+    public boolean isSelectedItem(final int position) {
+        if (null == mSelectedIndex.get(position)) {
+            return false;
+        }
+        return mSelectedIndex.get(position);
+    }
+
+    @Override
+/*
+函数功能：在activity内容发生局部变动的时候回调该函数计算便签的数量
+*/
+    protected void onContentChanged() {
+        super.onContentChanged();
+//执行基类函数
+        calcNotesCount();
+    }
+
+    @Override
+/*
+函数功能：在activity光标发生局部变动的时候回调该函数计算便签的数量
+*/
+    public void changeCursor(Cursor cursor) {
+        super.changeCursor(cursor);
+//执行基类函数
+        calcNotesCount();
+    }
+/*
+函数功能：计算便签数量
+*/
+    private void calcNotesCount() {
+        mNotesCount = 0;
+        for (int i = 0; i < getCount(); i++) {//获取总数同时遍历
+            Cursor c = (Cursor) getItem(i);
+            if (c != null) {
+                if (NoteItemData.getNoteType(c) == Notes.TYPE_NOTE) {
+                    mNotesCount++;
+//若该位置不为空并且文本类型为便签就+1
+                }
+            } else {
+                Log.e(TAG, "Invalid cursor");
+                return;
+            }
+//否则报错
+        }
+    }
+}