C++ 新手，未定义的引用
New to C++, undefined reference
通常我在 java 编程，也有一些 C 的基本概念（header，make 文件，函数，指针，C 编程和使用汇编函数[在大学]，forks，线程、信号量、管道）。
我正在尝试用 C++ 创建一个简单的程序以添加到我的 git 存储库并增加经验。
基本上在我调用 类 的主要部分：Categoty 和 CategoryList。
一个类别列表可以有零个或多个类别objects。
问题：
代码报错："undefined reference" 基本上在main.
CategoryList *cat = new CategoryList();
Category *c = new Category("Banana","Sobre bananas");
cat->addCategory(*c);
我想简单地创建一个列表，然后向该列表添加一个元素。
代码：
类别列表Header:
#ifndef CATEGORYLIST_H
#define CATEGORYLIST_H
#include <./src/Domain/Category.h>
#include <set>
using namespace std;
class CategoryList{
protected:
/**
* CATEGORY LIST
**/
set<Category> categorySet;
public:
CategoryList();
CategoryList(set<Category> c);
void addCategory(Category c);
int main();
private:
};
#endif // CATEGORYLIST_H
类别列表 Cpp：
#include "categorylist.h"
CategoryList::CategoryList(){
this->categorySet = set<Category>();
}
CategoryList::CategoryList(set<Category> list){
this->categorySet = list;
}
void CategoryList::addCategory(Category c){
this->categorySet.insert(c);
}
类别Header：
#ifndef CATEGORY_H
#define CATEGORY_H
#include <string>
using namespace std;
class Category{
protected:
string name;
string description;
public:
Category(string name, string description);
private:
};
#endif // CATEGORY_H
类别 Cpp：
#include "Category.h"
/**
*
* CONSTRUCTOR
*
**/
Category::Category(string name, string description){
this->name = name;
this->description = description;
}
主要cpp：
#include "firstcplusplusqt5program.h"
#include <QApplication>
#include <iostream>
#include <string>
#include "List/categorylist.h"
#include "Domain/Category.h"
using namespace std;
void simpleTest();
int main(int argc, char *argv[]){
simpleTest();
QApplication app(argc, argv);
FirstCplusPlusQt5Program w;
w.show();
return app.exec();
}
/**
*
* USE THIS FUNCION TO TESTE SIMPLE FUNCTIONS ON STARTUP
*
**/
void simpleTest(){
cout << "Welcome to José Rodrigues first cpp program." << endl;
for (int i = 0 ; i < 3 ; i++){
cout << "Count " << i << endl;
}
CategoryList *cat = new CategoryList();
Category *c = new Category("Banana","Sobre bananas");
cat->addCategory(*c);
}
我使用的IDE（Kdevelop、Netbeans、QT Creator）在此配置中没有显示任何错误。所以只有编译器给出错误：
/home/arch-admin/Git/FirstCplusPlusQtApp/FirstCplusPlusQt5Program/build> /usr/bin/ninja firstcplusplusqt5program
[1/4] Automatic MOC for target firstcplusplusqt5program
[2/3] Building CXX object CMakeFiles/firstcplusplusqt5program.dir/src/main.cpp.o
[3/3] Linking CXX executable firstcplusplusqt5program
FAILED: firstcplusplusqt5program
: && /usr/bin/c++ -g -rdynamic CMakeFiles/firstcplusplusqt5program.dir/src/main.cpp.o CMakeFiles/firstcplusplusqt5program.dir/src/firstcplusplusqt5program.cpp.o CMakeFiles/firstcplusplusqt5program.dir/firstcplusplusqt5program_autogen/moc_compilation.cpp.o -o firstcplusplusqt5program /usr/lib/libQt5Widgets.so.5.9.0 /usr/lib/libQt5Gui.so.5.9.0 /usr/lib/libQt5Core.so.5.9.0 && :
CMakeFiles/firstcplusplusqt5program.dir/src/main.cpp.o: In function `simpleTest()':
/home/arch-admin/Git/FirstCplusPlusQtApp/FirstCplusPlusQt5Program/build/../src/main.cpp:37: undefined reference to `CategoryList::CategoryList()'
/home/arch-admin/Git/FirstCplusPlusQtApp/FirstCplusPlusQt5Program/build/../src/main.cpp:38: undefined reference to `Category::Category(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >)'
/home/arch-admin/Git/FirstCplusPlusQtApp/FirstCplusPlusQt5Program/build/../src/main.cpp:39: undefined reference to `CategoryList::addCategory(Category)'
collect2: error: ld returned 1 exit status
ninja: build stopped: subcommand failed.
*** Failure: Exit code 1 ***
项目结构（src 只是因为大小）：
`-- src
| |-- Controller
| |-- Domain
| | |-- Author.cpp
| | |-- Author.h
| | |-- Category.cpp
| | |-- Category.h
| | |-- annotation.cpp
| | `-- annotation.h
| |-- List
| | |-- categorylist.cpp
| | `-- categorylist.h
| |-- PlantUmlGenerator
| |-- UI
| |-- Utils
| | |-- utils.cpp
| | `-- utils.h
| |-- firstcplusplusqt5program.cpp
| |-- firstcplusplusqt5program.h
| |-- firstcplusplusqt5program.ui
| `-- main.cpp
会不会是生成文件？
在 Qt 项目中有一个文件 CmakeList.txt，我应该为依赖项更改这个配置文件吗？
提前谢谢你。
CmakeList.txt
cmake_minimum_required(VERSION 2.8.11)
project(FirstCplusPlusQt5Program)
# Find includes in corresponding build directories
set(CMAKE_INCLUDE_CURRENT_DIR ON)
# Instruct CMake to run moc automatically when needed.
set(CMAKE_AUTOMOC ON)
# Find the QtWidgets library
find_package(Qt5Widgets REQUIRED)
set(firstcplusplusqt5program_SRC
src/main.cpp
src/firstcplusplusqt5program.cpp
)
# Create code from a list of Qt designer ui files.
#set(CMAKE_AUTOUIC ON) # use this if you have CMake 3.x instead of the following
qt5_wrap_ui(firstcplusplusqt5program_SRC src/firstcplusplusqt5program.ui)
# Tell CMake to create the helloworld executable
add_executable(firstcplusplusqt5program ${firstcplusplusqt5program_SRC})
# Use the Widgets module from Qt 5.
target_link_libraries(firstcplusplusqt5program Qt5::Widgets)
# Install the executable
install(TARGETS firstcplusplusqt5program DESTINATION bin)
您需要将所有 .cpp 文件添加到您的 CMakeList.txt
...
set(firstcplusplusqt5program_SRC
src/main.cpp
src/firstcplusplusqt5program.cpp
src/List/categoryList.cpp
src/Domain/Category.cpp
...
)
...
通常我在 java 编程，也有一些 C 的基本概念（header，make 文件，函数，指针，C 编程和使用汇编函数[在大学]，forks，线程、信号量、管道）。
我正在尝试用 C++ 创建一个简单的程序以添加到我的 git 存储库并增加经验。
基本上在我调用 类 的主要部分：Categoty 和 CategoryList。
一个类别列表可以有零个或多个类别objects。
问题：
代码报错："undefined reference" 基本上在main.
CategoryList *cat = new CategoryList();
Category *c = new Category("Banana","Sobre bananas");
cat->addCategory(*c);
我想简单地创建一个列表，然后向该列表添加一个元素。
代码：
类别列表Header:
#ifndef CATEGORYLIST_H
#define CATEGORYLIST_H
#include <./src/Domain/Category.h>
#include <set>
using namespace std;
class CategoryList{
protected:
/**
* CATEGORY LIST
**/
set<Category> categorySet;
public:
CategoryList();
CategoryList(set<Category> c);
void addCategory(Category c);
int main();
private:
};
#endif // CATEGORYLIST_H
类别列表 Cpp：
#include "categorylist.h"
CategoryList::CategoryList(){
this->categorySet = set<Category>();
}
CategoryList::CategoryList(set<Category> list){
this->categorySet = list;
}
void CategoryList::addCategory(Category c){
this->categorySet.insert(c);
}
类别Header：
#ifndef CATEGORY_H
#define CATEGORY_H
#include <string>
using namespace std;
class Category{
protected:
string name;
string description;
public:
Category(string name, string description);
private:
};
#endif // CATEGORY_H
类别 Cpp：
#include "Category.h"
/**
*
* CONSTRUCTOR
*
**/
Category::Category(string name, string description){
this->name = name;
this->description = description;
}
主要cpp：
#include "firstcplusplusqt5program.h"
#include <QApplication>
#include <iostream>
#include <string>
#include "List/categorylist.h"
#include "Domain/Category.h"
using namespace std;
void simpleTest();
int main(int argc, char *argv[]){
simpleTest();
QApplication app(argc, argv);
FirstCplusPlusQt5Program w;
w.show();
return app.exec();
}
/**
*
* USE THIS FUNCION TO TESTE SIMPLE FUNCTIONS ON STARTUP
*
**/
void simpleTest(){
cout << "Welcome to José Rodrigues first cpp program." << endl;
for (int i = 0 ; i < 3 ; i++){
cout << "Count " << i << endl;
}
CategoryList *cat = new CategoryList();
Category *c = new Category("Banana","Sobre bananas");
cat->addCategory(*c);
}
我使用的IDE（Kdevelop、Netbeans、QT Creator）在此配置中没有显示任何错误。所以只有编译器给出错误：
/home/arch-admin/Git/FirstCplusPlusQtApp/FirstCplusPlusQt5Program/build> /usr/bin/ninja firstcplusplusqt5program
[1/4] Automatic MOC for target firstcplusplusqt5program
[2/3] Building CXX object CMakeFiles/firstcplusplusqt5program.dir/src/main.cpp.o
[3/3] Linking CXX executable firstcplusplusqt5program
FAILED: firstcplusplusqt5program
: && /usr/bin/c++ -g -rdynamic CMakeFiles/firstcplusplusqt5program.dir/src/main.cpp.o CMakeFiles/firstcplusplusqt5program.dir/src/firstcplusplusqt5program.cpp.o CMakeFiles/firstcplusplusqt5program.dir/firstcplusplusqt5program_autogen/moc_compilation.cpp.o -o firstcplusplusqt5program /usr/lib/libQt5Widgets.so.5.9.0 /usr/lib/libQt5Gui.so.5.9.0 /usr/lib/libQt5Core.so.5.9.0 && :
CMakeFiles/firstcplusplusqt5program.dir/src/main.cpp.o: In function `simpleTest()':
/home/arch-admin/Git/FirstCplusPlusQtApp/FirstCplusPlusQt5Program/build/../src/main.cpp:37: undefined reference to `CategoryList::CategoryList()'
/home/arch-admin/Git/FirstCplusPlusQtApp/FirstCplusPlusQt5Program/build/../src/main.cpp:38: undefined reference to `Category::Category(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >)'
/home/arch-admin/Git/FirstCplusPlusQtApp/FirstCplusPlusQt5Program/build/../src/main.cpp:39: undefined reference to `CategoryList::addCategory(Category)'
collect2: error: ld returned 1 exit status
ninja: build stopped: subcommand failed.
*** Failure: Exit code 1 ***
项目结构（src 只是因为大小）：
`-- src
| |-- Controller
| |-- Domain
| | |-- Author.cpp
| | |-- Author.h
| | |-- Category.cpp
| | |-- Category.h
| | |-- annotation.cpp
| | `-- annotation.h
| |-- List
| | |-- categorylist.cpp
| | `-- categorylist.h
| |-- PlantUmlGenerator
| |-- UI
| |-- Utils
| | |-- utils.cpp
| | `-- utils.h
| |-- firstcplusplusqt5program.cpp
| |-- firstcplusplusqt5program.h
| |-- firstcplusplusqt5program.ui
| `-- main.cpp
会不会是生成文件？
在 Qt 项目中有一个文件 CmakeList.txt，我应该为依赖项更改这个配置文件吗？
提前谢谢你。
CmakeList.txt
cmake_minimum_required(VERSION 2.8.11)
project(FirstCplusPlusQt5Program)
# Find includes in corresponding build directories
set(CMAKE_INCLUDE_CURRENT_DIR ON)
# Instruct CMake to run moc automatically when needed.
set(CMAKE_AUTOMOC ON)
# Find the QtWidgets library
find_package(Qt5Widgets REQUIRED)
set(firstcplusplusqt5program_SRC
src/main.cpp
src/firstcplusplusqt5program.cpp
)
# Create code from a list of Qt designer ui files.
#set(CMAKE_AUTOUIC ON) # use this if you have CMake 3.x instead of the following
qt5_wrap_ui(firstcplusplusqt5program_SRC src/firstcplusplusqt5program.ui)
# Tell CMake to create the helloworld executable
add_executable(firstcplusplusqt5program ${firstcplusplusqt5program_SRC})
# Use the Widgets module from Qt 5.
target_link_libraries(firstcplusplusqt5program Qt5::Widgets)
# Install the executable
install(TARGETS firstcplusplusqt5program DESTINATION bin)
您需要将所有 .cpp 文件添加到您的 CMakeList.txt
...
set(firstcplusplusqt5program_SRC
src/main.cpp
src/firstcplusplusqt5program.cpp
src/List/categoryList.cpp
src/Domain/Category.cpp
...
)
...