编译错误Arduino c++对象库

Question

我正在编写一个用于蓝牙通信的c++ Arduino库。我实现了一种机制，以便注册一个自定义函数，以便在来自BT连接的某个字节时执行。实际上是一种Java Hashmap。一切都很好，但当我试图在构造函数中注册库对象的方法时，我得到了一些我无法理解的编译错误。我使用Arduino IDE 1.6.9与Ubuntu 16.04 LTS 64位。该板是Arduino UNO。在代码下面，标题:

#ifndef BlueHartwin_H
#define BlueHartwin_H
    #include <SoftwareSerial.h>
    #include <Streaming.h>;
    #include <Arduino.h>
    #define START_TX 254
    #define STOP_TX 255
    typedef void (* CmdFuncPtr) (); // this is a typedef to command functions

    class BlueHartwin {
    public:
        BlueHartwin(byte bluetoothTx,byte bluetoothRx,long baudRate);
        ~BlueHartwin();
        boolean registerCmd(byte id,CmdFuncPtr cmdFuncPtr);
        boolean unRegisterCmd(byte id,CmdFuncPtr cmdFuncPtr);
        boolean runCmd(byte id);
        void setDataLength(byte dataLength);
        byte getDataLength();
        byte getIncomingByte();
        void txSwitchOff(void);
        void txSwitchOn(void);
        bool isTx();
        boolean available();
        boolean read();
        void write(byte data,boolean endLine);

    private:
        CmdFuncPtr setOfCmds[255];
        byte mDataLength;
        bool tx;
        byte incomingByte;
    };
    #endif

身体:

#include "BlueHartwin.h";
/*
 * Reserved command IDs:
 * 14,
 * 15
*/

SoftwareSerial bluetooth(7,8);

BlueHartwin::BlueHartwin(byte bluetoothTx,byte bluetoothRx,long baudRate){
    bluetooth = SoftwareSerial(bluetoothTx,bluetoothRx);
    bluetooth.begin(baudRate);
    for (int i=0;i<=255;i++) {
        setOfCmds[i]=NULL;
    }
    tx=false;
    registerCmd(14,&txSwitchOff);
    registerCmd(15,&txSwitchOn);
}
BlueHartwin::~BlueHartwin(){
}
boolean BlueHartwin::registerCmd(byte id,CmdFuncPtr cmdFuncPtr){
    if (setOfCmds[id]==NULL) {
        setOfCmds[id]=cmdFuncPtr;   
        return true;
    } else return false;
}
boolean BlueHartwin::unRegisterCmd(byte id,CmdFuncPtr cmdFuncPtr){
    setOfCmds[id]=NULL; 
    return true;
}

boolean BlueHartwin::runCmd(byte id){
    if (setOfCmds[id]!=NULL) {
        setOfCmds[id]();
        return true;
    } else return false;
}

void BlueHartwin::setDataLength(byte dataLength) {
    mDataLength=dataLength;
}
byte BlueHartwin::getDataLength(){
    return mDataLength;
}
byte BlueHartwin::getIncomingByte(){
    return incomingByte;
}
boolean BlueHartwin::isTx(){
    return tx;
}
void BlueHartwin::txSwitchOff(void){
  tx=false;
  Serial<<"now tx is "<<tx<<endl;
}
void BlueHartwin::txSwitchOn(void){
  tx=true;
  Serial<<"now tx is "<<tx<<endl;
}
boolean BlueHartwin::available(){
    return bluetooth.available();
}
boolean BlueHartwin::read(){
    if (bluetooth.available()>0)
        {
         incomingByte=bluetooth.read();
         Serial << "Incoming byte " << incomingByte<<endl;
         return runCmd(incomingByte);
        }
    return false;
}

void BlueHartwin::write(byte data,boolean endLine){
    if (tx) {
        if (endLine) bluetooth << data << endl;
        else bluetooth<<data;
    }
}

错误:

/home/paolo/ARDUINO/arduino-1.6.9/libraries/BlueHartwin/BlueHartwin.cpp: In constructor 'BlueHartwin::BlueHartwin(byte, byte, long int)':
/home/paolo/ARDUINO/arduino-1.6.9/libraries/BlueHartwin/BlueHartwin.cpp:21:18: error: ISO C++ forbids taking the address of an unqualified or parenthesized non-static member function to form a pointer to member function.  Say '&BlueHartwin::txSwitchOff' [-fpermissive]
  registerCmd(14,&txSwitchOff);
                  ^
/home/paolo/ARDUINO/arduino-1.6.9/libraries/BlueHartwin/BlueHartwin.cpp:21:29: error: no matching function for call to 'BlueHartwin::registerCmd(int, void (BlueHartwin::*)())'
  registerCmd(14,&txSwitchOff);
                             ^
/home/paolo/ARDUINO/arduino-1.6.9/libraries/BlueHartwin/BlueHartwin.cpp:21:29: note: candidate is:
In file included from /home/paolo/ARDUINO/arduino-1.6.9/libraries/BlueHartwin/BlueHartwin.cpp:1:0:
/home/paolo/ARDUINO/arduino-1.6.9/libraries/BlueHartwin/BlueHartwin.h:19:10: note: boolean BlueHartwin::registerCmd(byte, CmdFuncPtr)
  boolean registerCmd(byte id,CmdFuncPtr cmdFuncPtr);
          ^
/home/paolo/ARDUINO/arduino-1.6.9/libraries/BlueHartwin/BlueHartwin.h:19:10: note:   no known conversion for argument 2 from 'void (BlueHartwin::*)()' to 'CmdFuncPtr {aka void (*)()}'
/home/paolo/ARDUINO/arduino-1.6.9/libraries/BlueHartwin/BlueHartwin.cpp:22:18: error: ISO C++ forbids taking the address of an unqualified or parenthesized non-static member function to form a pointer to member function.  Say '&BlueHartwin::txSwitchOn' [-fpermissive]
  registerCmd(15,&txSwitchOn);
                  ^
/home/paolo/ARDUINO/arduino-1.6.9/libraries/BlueHartwin/BlueHartwin.cpp:22:28: error: no matching function for call to 'BlueHartwin::registerCmd(int, void (BlueHartwin::*)())'
  registerCmd(15,&txSwitchOn);
                            ^
/home/paolo/ARDUINO/arduino-1.6.9/libraries/BlueHartwin/BlueHartwin.cpp:22:28: note: candidate is:
In file included from /home/paolo/ARDUINO/arduino-1.6.9/libraries/BlueHartwin/BlueHartwin.cpp:1:0:
/home/paolo/ARDUINO/arduino-1.6.9/libraries/BlueHartwin/BlueHartwin.h:19:10: note: boolean BlueHartwin::registerCmd(byte, CmdFuncPtr)
  boolean registerCmd(byte id,CmdFuncPtr cmdFuncPtr);
          ^
/home/paolo/ARDUINO/arduino-1.6.9/libraries/BlueHartwin/BlueHartwin.h:19:10: note:   no known conversion for argument 2 from 'void (BlueHartwin::*)()' to 'CmdFuncPtr {aka void (*)()}'
exit status 1
Errore durante la compilazione per la scheda Arduino/Genuino Uno.

如果我在构造函数中更改行:

registerCmd(14,&txSwitchOff);
registerCmd(15,&txSwitchOn);

registerCmd(14,&BlueHartwin::txSwitchOff);
registerCmd(15,&BlueHartwin::txSwitchOn);

我得到这个错误:

/home/paolo/ARDUINO/arduino-1.6.9/libraries/BlueHartwin/BlueHartwin.cpp: In constructor 'BlueHartwin::BlueHartwin(byte, byte, long int)':
/home/paolo/ARDUINO/arduino-1.6.9/libraries/BlueHartwin/BlueHartwin.cpp:21:42: error: no matching function for call to 'BlueHartwin::registerCmd(int, void (BlueHartwin::*)())'
  registerCmd(14,&BlueHartwin::txSwitchOff);
                                          ^
/home/paolo/ARDUINO/arduino-1.6.9/libraries/BlueHartwin/BlueHartwin.cpp:21:42: note: candidate is:
In file included from /home/paolo/ARDUINO/arduino-1.6.9/libraries/BlueHartwin/BlueHartwin.cpp:1:0:
/home/paolo/ARDUINO/arduino-1.6.9/libraries/BlueHartwin/BlueHartwin.h:19:10: note: boolean BlueHartwin::registerCmd(byte, CmdFuncPtr)
  boolean registerCmd(byte id,CmdFuncPtr cmdFuncPtr);
          ^
/home/paolo/ARDUINO/arduino-1.6.9/libraries/BlueHartwin/BlueHartwin.h:19:10: note:   no known conversion for argument 2 from 'void (BlueHartwin::*)()' to 'CmdFuncPtr {aka void (*)()}'
/home/paolo/ARDUINO/arduino-1.6.9/libraries/BlueHartwin/BlueHartwin.cpp:22:41: error: no matching function for call to 'BlueHartwin::registerCmd(int, void (BlueHartwin::*)())'
  registerCmd(15,&BlueHartwin::txSwitchOn);
                                         ^
/home/paolo/ARDUINO/arduino-1.6.9/libraries/BlueHartwin/BlueHartwin.cpp:22:41: note: candidate is:
In file included from /home/paolo/ARDUINO/arduino-1.6.9/libraries/BlueHartwin/BlueHartwin.cpp:1:0:
/home/paolo/ARDUINO/arduino-1.6.9/libraries/BlueHartwin/BlueHartwin.h:19:10: note: boolean BlueHartwin::registerCmd(byte, CmdFuncPtr)
  boolean registerCmd(byte id,CmdFuncPtr cmdFuncPtr);
          ^
/home/paolo/ARDUINO/arduino-1.6.9/libraries/BlueHartwin/BlueHartwin.h:19:10: note:   no known conversion for argument 2 from 'void (BlueHartwin::*)()' to 'CmdFuncPtr {aka void (*)()}'
exit status 1
Errore durante la compilazione per la scheda Arduino/Genuino Uno.

提前感谢您的帮助!

Answer 1

Mate，您的txSwitchOn/Off方法是实例方法-它们需要this才能正常工作。

在另一边，你的CmdFuncPtr是一个不依赖于任何东西的函数的定义。

---

有多少这样的设备(由您的库支持)是假定Arduino在任何时候处理?

如果只有一个，那么就声明所有东西都是静态的，将构造函数重命名为"static void init()"，将析构函数重命名为"static void disconnect()"，等等。您将使类充当函数的命名上下文(所有静态)。