QMultiMap is a class from the Qt Toolkit which is a convenience QMap subclass that provides multi-valued maps. The QMap class is a template class that provides a red-black-tree-based dictionary.
Questions tagged [qmultimap]
11 questions
6
votes
2 answers
QMap::insertMulti or QMultiMap?
What should i use between QMap::insertMulti and QMultiMap to handle :
2 -> abc
2 -> def
3 -> ghi
3 -> jkl
What's the difference enter the 2 solutions ?
canardman
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6
votes
2 answers
Order of items in QMap and QMultiMap
I would like to use QMultiMap (which is derived from QMap) to store key/value pairs. Since I can have keys multiple times I would prefer to use QMultiMap.
Assume I would insert the following pairs in the given order:
"C" -> 5
"A" -> 10
"B" -> 77
"B"…
Silicomancer
- 8,604
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2
votes
1 answer
exporting QMultiMap to QML
I have following QObject:
#ifndef UETYPES
#define UETYPES
#include
#include
#include
#include
#include
#include "../database/ueuserrecord.h"
#include "../database/ueorderrecord.h"
class UeTypes…
KernelPanic
- 2,328
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1
vote
1 answer
Is it possible to use to use QMultiMap::ConstIterator in own template class?
I want to iterate over a QMultiMap using
QMultiMap::const_iterator it;`
but the compiler complains
error: expected ‘;’ before ‘it’
resulting in a
error: ‘it’ was not declared in this scope
for every usage. I tried…
mbx
- 6,292
- 6
- 58
- 91
1
vote
1 answer
QMultiMap And QDataStream
I saw in QtAssistant that QDataStream supports QMap and QMultiMap inherits QMap . Does Qt support QMultiMap for serialization with QDataStream ?
amiref
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- 7
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1
vote
1 answer
Is this use of QMap potentially harmful?
#include
template
TKey lastKeyOf(const QMap& map)
{
if (map.isEmpty())
throw something;
return (map.end() - 1).key();
}
The reason I ask is that:
template
Martin Drozdik
- 12,742
- 22
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- 146
0
votes
1 answer
Unused container warning when iterating over values of a specific key in QMultiMap
i get an "allocating unneeded temporary container" warning when i try to iterate over the values of a specific key in a QMultiMap:
QMultiHash testMap;
for (auto &&value : testMap.values("Specific Key"))
{
…
UrbanCee
- 1
- 1
0
votes
2 answers
QMultiMap with QVariant as key
I have a multimap with QVariant as key, but it's not working with QByteArray.
The funcion map.values("\xc2\x39\xc7\xe1") is returning all the values of the map.
This is a small example:
#include
#include
#include…
Fausto01
- 171
- 14
0
votes
1 answer
Why is this local QMultiMap detaching when modified?
To give some background: in my project I put a debug breakpoint inside QMap::detach_helper because I wanted to see if I could spot any occurrences when implicitly shared QMaps were detaching due to an oversight e.g. using find when constFind could…
Patrick Parker
- 4,863
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0
votes
1 answer
QMultiMap with struct as key and struct as value, comparison operators
I have two structs, for example, first struct as key in QMultiMap:
struct KeyStruct
{
int keydata1;
int keydata2;
int keydata3;
bool operator < ( const KeyStruct& o ) const
{
return keydata1 < o.keydata1 || keydata2 <…
esterlein
- 91
- 1
- 10
-1
votes
1 answer
How to get key from value in QMultiMap?
I have QMultiMap as follows:
QMultiMap paramIDMap, paramValueMap;
My value is "xyz" and i want to take it's key.
Example: paramIDMap.getkey("xyz") like this
How to do this?
Expected output should return key.
Cm Jagtap
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