请教C++编译问题，关于模板类和虚函数
我理解得不是太清楚，请大家帮我看看。
g++ a.cpp -o test
error:
command.cpp: In function ‘int main()’:
command.cpp:92: error: no matching function for call to ‘SimpleCommand<MyClass>::SimpleCommand(MyClass&, <unresolved overloaded function type>)’
command.cpp:29: note: candidates are: SimpleCommand<ReceiverType>::SimpleCommand(ReceiverType&, void (ReceiverType::*)()) [with ReceiverType = MyClass]
command.cpp:26: note: SimpleCommand<MyClass>::SimpleCommand(const SimpleCommand<MyClass>&)
-----------------------------------------------------
#include <stdio.h>
#include <stdlib.h>
#include <string>
#include <vector>
#include <algorithm>
using namespace std;
class MyClass
{
public:
void Display1()
{
printf("MyClass.Display1() called\n");
}
void Display2()
{
printf("MyClass.Display2() called\n");
}
};
class Command
{
public:
virtual ~Command() {}
virtual void Execute()=0;
};
template<class ReceiverType>
class SimpleCommand:public Command{
public:
typedef void (ReceiverType::*Action)();//function ptr
SimpleCommand(ReceiverType &r,Action a)
:_receiver(r),
_action(a)
{
}
void Execute()
{
(_receiver._action)();
}
private:
ReceiverType _receiver;
Action _action;
};
class NormalCommand1:public Command{
public:
NormalCommand1(MyClass &r)
:_receiver(r)
{
}
void Execute()
{
_receiver.Display1();
}
private:
MyClass _receiver;
};
class NormalCommand2:public Command{
public:
NormalCommand2(MyClass &r)
:_receiver(r)
{
}
void Execute()
{
_receiver.Display2();
}
private:
MyClass _receiver;
};
class MacroCommand:public Command
{
public:
MacroCommand() {}
void Add(Command *c)
{
_commands.push_back(c);
}
void Remove(Command *c)
{
remove(_commands.begin(),_commands.end(),c);
}
virtual void Execute()
{
for(vector<Command *>::iterator iter=_commands.begin();iter!=
_commands.end();iter++)
(*iter)->Execute();
}
private:
vector<Command *>_commands;
};
int main()
{
MyClass m;
Command *a=new SimpleCommand<MyClass>(m,m.Display1);
a->Execute();
Command *b=new NormalCommand1(m);
b->Execute();
Command *c=new NormalCommand2(m);
c->Execute();
MacroCommand micro_command;
micro_command.Add(a);
micro_command.Add(b);
micro_command.Add(c);
micro_command.Execute();
return 0;
}
[解决办法]
Command *a=new SimpleCommand<MyClass>(m,&MyClass::Display1);
[解决办法]
成员函数指针使用错误, 看一下怎么成员函数指针是怎么用的吧
[解决办法]
void Execute() { (_receiver.*_action)(); /// 注意这个地方 }
[解决办法]