using CMap
-
I have declared the following in my application. "CMap < CString,LPCSTR,CWnd*,CWnd* > m_map" I have a windows explorer like setup. When i click a node in the tree i need to display an MDI Window. So i have mapped the node item's text (LPCSTR) to that of the window pointer .So when i click a node i use CMap to get the window pointer and display the window. Now when i alternatively click the windows i get the window pointer and i want to correspondingly shift the focus on the tree items. So my question is how do i look up the key ( i.e LPCSTR) when i have the value (i.e.. CWnd*). . laiju
Is there any reason you're using CMap instead of map, in the C++ standard library ? CMap, CList, CArray,etc. were all written only as a stopgap until the stl came online. They are really crappy in comparison. You need to build a second map that goes the other way. Even if you iterate through the keys collection, checking for the value ( which is a very lousy thing to have to do ), there's no guarentee that your value appears only once, so there's no guarentee you'll find the right key. Christian Graus - Microsoft MVP - C++
-
I have declared the following in my application. "CMap < CString,LPCSTR,CWnd*,CWnd* > m_map" I have a windows explorer like setup. When i click a node in the tree i need to display an MDI Window. So i have mapped the node item's text (LPCSTR) to that of the window pointer .So when i click a node i use CMap to get the window pointer and display the window. Now when i alternatively click the windows i get the window pointer and i want to correspondingly shift the focus on the tree items. So my question is how do i look up the key ( i.e LPCSTR) when i have the value (i.e.. CWnd*). . laiju
You'll need to iterate through all keys and check if each key's value matches the
CWnd*you're searching for. /ravi My new year's resolution: 2048 x 1536 Home | Articles | Freeware | Music ravib@ravib.com -
You'll need to iterate through all keys and check if each key's value matches the
CWnd*you're searching for. /ravi My new year's resolution: 2048 x 1536 Home | Articles | Freeware | Music ravib@ravib.comBut that only works if each CWnd is only in there once. And it's damn ugly. Christian Graus - Microsoft MVP - C++
-
But that only works if each CWnd is only in there once. And it's damn ugly. Christian Graus - Microsoft MVP - C++
True. What he really needs is a multimap. /ravi My new year's resolution: 2048 x 1536 Home | Articles | Freeware | Music ravib@ravib.com
-
True. What he really needs is a multimap. /ravi My new year's resolution: 2048 x 1536 Home | Articles | Freeware | Music ravib@ravib.com
Does multimap let you search the values ? Christian Graus - Microsoft MVP - C++
-
Does multimap let you search the values ? Christian Graus - Microsoft MVP - C++
Sorry, I meant a bi-directional map, not a multi-map. :-O /ravi My new year's resolution: 2048 x 1536 Home | Articles | Freeware | Music ravib@ravib.com
-
Sorry, I meant a bi-directional map, not a multi-map. :-O /ravi My new year's resolution: 2048 x 1536 Home | Articles | Freeware | Music ravib@ravib.com
I have used
mapandmultimap, and read about but never usedhash_mapandhash_multimap. What exactly do you mean by a bi-directional map? I always thought bi-directional containers were containers that had both forward and reverse iterators, but that definition does not seem to be what is being discussed here. What I think you mean is a map where both the key and value are unique, and has afind()member that can find either the key or the value. Is there such a beast? If so what is it called and where can I get it? Currently I am just using amapfor this functionality, I check to make sure the value is unique before I add a new value to the map, and I sequentially iterate the map, comparing values, until I find the keyvalue I am looking for. If there is a better implementation out there I would be interested in learning about it.
"You're obviously a superstar." - Christian Graus about me - 12 Feb '03 "Obviously ??? You're definitely a superstar!!!" - mYkel - 21 Jun '04 "There's not enough blatant self-congratulatory backslapping in the world today..." - HumblePie - 21 Jun '05 Within you lies the power for good - Use it!
-
I have declared the following in my application. "CMap < CString,LPCSTR,CWnd*,CWnd* > m_map" I have a windows explorer like setup. When i click a node in the tree i need to display an MDI Window. So i have mapped the node item's text (LPCSTR) to that of the window pointer .So when i click a node i use CMap to get the window pointer and display the window. Now when i alternatively click the windows i get the window pointer and i want to correspondingly shift the focus on the tree items. So my question is how do i look up the key ( i.e LPCSTR) when i have the value (i.e.. CWnd*). . laiju
a tought ... if the strings are unique, make a map that points to ( a pointer to ) a structure containing a CWnd and a HTREEITEM when you create the CWnd, attach the structure to the CWnd ( as a member of the class ) when you create the Tree Item, attach the structure to the Item ( CTreeCtrl::SetItemData ) when you click on the window, you can find exactly which item to highlight; and when you click on the tree item you have the pointer to the CWnd.
Maximilien Lincourt Your Head A Splode - Strong Bad
-
I have used
mapandmultimap, and read about but never usedhash_mapandhash_multimap. What exactly do you mean by a bi-directional map? I always thought bi-directional containers were containers that had both forward and reverse iterators, but that definition does not seem to be what is being discussed here. What I think you mean is a map where both the key and value are unique, and has afind()member that can find either the key or the value. Is there such a beast? If so what is it called and where can I get it? Currently I am just using amapfor this functionality, I check to make sure the value is unique before I add a new value to the map, and I sequentially iterate the map, comparing values, until I find the keyvalue I am looking for. If there is a better implementation out there I would be interested in learning about it.
"You're obviously a superstar." - Christian Graus about me - 12 Feb '03 "Obviously ??? You're definitely a superstar!!!" - mYkel - 21 Jun '04 "There's not enough blatant self-congratulatory backslapping in the world today..." - HumblePie - 21 Jun '05 Within you lies the power for good - Use it!
PJ Arends wrote: What I think you mean is a map where both the key and value are unique, and has a find() member that can find either the key or the value. Yes, exactly. PJ Arends wrote: If so what is it called and where can I get it? I don't know. I'm tempted to write one, but I doubt I'll come up with anything revolutionary (i.e. very efficient). A hashmap of pairs, with uniqueness enforced on values is what comes to mind. /ravi My new year's resolution: 2048 x 1536 Home | Articles | Freeware | Music ravib@ravib.com
-
PJ Arends wrote: What I think you mean is a map where both the key and value are unique, and has a find() member that can find either the key or the value. Yes, exactly. PJ Arends wrote: If so what is it called and where can I get it? I don't know. I'm tempted to write one, but I doubt I'll come up with anything revolutionary (i.e. very efficient). A hashmap of pairs, with uniqueness enforced on values is what comes to mind. /ravi My new year's resolution: 2048 x 1536 Home | Articles | Freeware | Music ravib@ravib.com
Thanks Ravi. I thought you were refering to an already existing implementation that I did not know about. I guess I have to stick to my home-brewed hack.
"You're obviously a superstar." - Christian Graus about me - 12 Feb '03 "Obviously ??? You're definitely a superstar!!!" - mYkel - 21 Jun '04 "There's not enough blatant self-congratulatory backslapping in the world today..." - HumblePie - 21 Jun '05 Within you lies the power for good - Use it!
-
Thanks Ravi. I thought you were refering to an already existing implementation that I did not know about. I guess I have to stick to my home-brewed hack.
"You're obviously a superstar." - Christian Graus about me - 12 Feb '03 "Obviously ??? You're definitely a superstar!!!" - mYkel - 21 Jun '04 "There's not enough blatant self-congratulatory backslapping in the world today..." - HumblePie - 21 Jun '05 Within you lies the power for good - Use it!
An off-the-sheld bidirectional map is provided here[^]; unfortunately, it doesn't work with MSVC 7.1. For a more comprehensive solution, allow me to suggest you take a look at the Boost Multi-index Containers Library[^], which enables the construction of bidirectional maps and more. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo Want a Boost forum in Code Project? Vote here[^]!
-
An off-the-sheld bidirectional map is provided here[^]; unfortunately, it doesn't work with MSVC 7.1. For a more comprehensive solution, allow me to suggest you take a look at the Boost Multi-index Containers Library[^], which enables the construction of bidirectional maps and more. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo Want a Boost forum in Code Project? Vote here[^]!
Thanks Joaquín, your CP article looks interesting. I will DL the code and play with it to see if it fits my needs:)
"You're obviously a superstar." - Christian Graus about me - 12 Feb '03 "Obviously ??? You're definitely a superstar!!!" - mYkel - 21 Jun '04 "There's not enough blatant self-congratulatory backslapping in the world today..." - HumblePie - 21 Jun '05 Within you lies the power for good - Use it!