function pointer array

I have a question on how to store methods from multiply other class in an array.
All this code is for an arduino controller. The AP_ATO class is instanced as myATO in its .cpp file.

In the .h file,

#include <AP_ATO.h>

typedef void (*inputHandler)();

class AP_expandedInput{
  ...
  inputHandler callback[8];
  ...

And then in the .cpp file,

void AP_expandedInput::runtime(){
  if (EIN_IRQ == LOW){
    uint8_t i;
		
    uint8_t* inputReg = expIn.inputArray();
		
    for (i=0 ; i<NUM_IO_PORTS ; i++){
      if (inputReg[i] == actionState[i]){
        (*callback[i])();
      }
    }
  }
}

void AP_expandedInput::addATOlowLevelSensor(uint8_t port){
  actionState[port] = HIGH;
  callback[port] = myATO::lowLevelReached;
}

I'm not really sure how I'm supposed to syntax that method from the AP_ATO class.

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callback[port] = myATO::lowLevelReached;
//or
callback[port] = myATO.lowLevelReached;

Last edited on

closed account (zb0S216C)

thejosheb wrote:

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callback[port] = myATO::lowLevelReached;
//or
callback[port] = myATO.lowLevelReached;

The type of "inputHandler" cannot take the address of a member-function. Instead, you must specify the class to which the function belongs during "inputHandler's"" declaration, like so:

typedef void( SomeClass:: *InputHander )( );

And then when creating a pointer, you must specify a function's address:

InputHandler NewHandler( &SomeClass::Function );

Calling a member-function through a function-pointer is a little strange:

( SomeClassInstance.*NewHandler )( );

_Wazzak

Last edited on

thejosheb (5)

so basically the array has to contain member-functions from only one class.

closed account (zb0S216C)

Yes. A pointer to a member-function can only reference instances of the class to which its bound to. In my above examples, "NewHandler" can only call the "SomeClass::Function" function of all instances of "SomeClass", unless you redirect the pointer to another member-function of the same class that matches the specification set by the function-pointer.

_Wazzak

Last edited on

thejosheb (5)

Alright thanks for the help.

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function pointer array