ruby-****@sourc*****
ruby-****@sourc*****
2012年 8月 22日 (水) 03:14:48 JST
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REMOTE_ADDR = 70.49.49.99
REMOTE_HOST =
URL = http://ruby-gnome2.sourceforge.jp/hiki.cgi?tut-gtk2-treev-trees
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@@ -161,15 +161,16 @@
One important thing to be notice is the sequential data organization within the tree store. This may be obvious from the way we set-up our array ((*list:*))
list = Array.new
- list[0] = GroceryItem.new(P_CATEGORY, true, 0, "Cleaning Supplies")
- list[1] = GroceryItem.new(P_CHILD, true, 1, "Paper Towels")
- list[2] = GroceryItem.new(P_CHILD, true, 3, "Toilet Paper")
- list[3] = GroceryItem.new(P_CATEGORY, true, 0, "Food")
- list[4] = GroceryItem.new(P_CHILD, true, 2, "Bread")
- list[5] = GroceryItem.new(P_CHILD, false, 1, "Butter")
- list[6] = GroceryItem.new(P_CHILD, true, 1, "Milk")
- list[7] = GroceryItem.new(P_CHILD, false, 3, "Chips")
- list[8] = GroceryItem.new(P_CHILD, true, 4, "Soda")
+ # Category Buy Qty Product
+ list[0] = GroceryItem.new(P_CATEGORY, true, 0, "Cleaning Supplies")
+ list[1] = GroceryItem.new(P_CHILD, true, 1, "Paper Towels")
+ list[2] = GroceryItem.new(P_CHILD, true, 3, "Toilet Paper")
+ list[3] = GroceryItem.new(P_CATEGORY, true, 0, "Food")
+ list[4] = GroceryItem.new(P_CHILD, true, 2, "Bread")
+ list[5] = GroceryItem.new(P_CHILD, false, 1, "Butter")
+ list[6] = GroceryItem.new(P_CHILD, true, 1, "Milk")
+ list[7] = GroceryItem.new(P_CHILD, false, 3, "Chips")
+ list[8] = GroceryItem.new(P_CHILD, true, 4, "Soda")
Parent/child relationship dictates that we bundle together all children of a parent below it. When later on application inserts new rows, particularly children, they have to be inserted into, or better immediately after, the list children of such a group. This makes indices to certain rows ephemeral. For instance if you store (memorize) an index to a certain row that index will became invalid after an insertion or a deletion of a row positioned before the element (row) for which you have stored (memorized) the index. Also the orderly sequential organization of the rows in a tree store allows you to readily process the data, since you can always be sure about locations of rows and the groupings of the children can be determined in a predictable manner. In our example program we exploited this fact in the loop calculating the totals for the parents by iterating through their groups of children: