Getting Strings into my library

Projects Libraries
1

Hello all, I'm writing a library that will control temperature and humidity or anything of the like. I'm getting "error: 'String' does not name a type" so I believe that I'm not including String.h correctly in Controller.cpp

If anyone could help me out and explain what I'm doing wrong I would really appreciate it. :grin:

Controller.h:

// Controller.h

class Controller
{
	public:
	Controller(int devicePin, int turnPoint, int leeway, bool inverted, char deviceName[16], char controlLabel[12]);
	
	void CheckController(int reading);
	bool State();
	String DeviceName();
	String ControlLabel();
	
	private:
	int _devicePin;
	int _turnPoint;
	int _leeway;
	bool _inverted;
	bool _state;
	char _deviceName[16];
	char _controlLabel[12];
};

class DualController
{
	public:
	DualController(int lowDevicePin, int highDevicePin,
		int lowTurnPoint, int highTurnPoint, char lowDeviceName[16],
		char highDeviceName[16], char controlLabel[12]);

	void CheckController(int reading);
	bool LowState();
	bool HighState();
	String HighDeviceName();
	String LowDeviceName();
	String ControlLabel();

	private:
	int _lowDevicePin;
	int _highDevicePin;
	int _lowTurnPoint;
	int _highTurnPoint;
	bool _lowState;
	bool _highState;
	char _lowDeviceName[16];
	char _highDeviceName[16];
	char _controlLabel[12];
};

Controller.cpp:

// Controller.cpp

#include <String.h>
#include "WProgram.h"
#include "Controller.h"
 
Controller::Controller(int devicePin, int turnPoint, int leeway, bool inverted, String deviceName, String controlLabel)
{
	pinMode(devicePin, OUTPUT);
	_devicePin = devicePin;
	_turnPoint = turnPoint;
	_leeway = leeway;
	_state = false;
	_inverted = inverted;
	
	deviceName.toCharArray(_deviceName, 16);
	controlLabel.toCharArray(_controlLabel, 12);
}

Controller::CheckController(int reading)
{
	if(_inverted)
	{
		if(reading<=_turnPoint && !state)
		{
			digitalWrite(_devicePin, HIGH);
			_state = true;
		}
		else
		{
			if(_state && reading >= (_turnPoint + leeway)
			{
				digitalWrite(_devicePin, LOW);
				_state = false;
			}
		}
	}
	else
	{
		if(reading>=turnPoint && !state)
		{
			digitalWrite(_devicePin, HIGH);
			_state = true;
		}
		else
		{
			if(reading <= (_turnPoint - 5) &&_state)
			{
				digitalWrite(_devicePin, LOW);
				state = false;
			}
		}
	}
}

Controller::State()
{
	return _state;
}

Controller::DeviceName()
{
	return String(_deviceName);
}

Controller::ControlLabel()
{
	return String(_controlLabel);
}

DualController::DualController(int lowDevicePin, int highDevicePin,
	int lowTurnPoint, int highTurnPoint, char lowDeviceName[16],
	char highDeviceName[16], char controlLabel[12])
{
	if(reading<=_lowTurnPoint && !lowState)
	{
		digitalWrite(_lowDevicePin, HIGH);
		_lowState = true;
	}
	else
	{
		if(_lowState && reading >= (_lowTurnPoint + leeway)
		{
			digitalWrite(_lowDevicePin, LOW);
			_lowState = false;
		}
	}
	
	if(reading>=_highTurnPoint && !_highState)
	{
		digitalWrite(_highDevicePin, HIGH);
		_highState = true;
	}
	else
	{
		if(reading <= (_highTurnPoint - 5) &&_highState)
		{
			digitalWrite(_highDevicePin, LOW);
			_highState = false;
		}
	}
}

DualController::LowState()
{
	return _lowState;
}

DualController::HighState()
{
	return _highState;
}

DualController::LowDeviceName()
{
	return String(_lowDeviceName)
}
	
DualController::HighDeviceName()
{
	return String(_highDeviceName);
}

DualController::ControlLabel()
{
	return String(_controlLabel)
}
2

Include 'String.h' in the header instead of the .cpp

your controller class declaration (.h) declares objects of type String but String's are unknown and not included till the cpp file.

3

Thanks Pyro_65! XD, I'll try it out as soon as I get back to my pc.

4

Better yet, quit using Strings. The internal storage is a char array. Why waste the resources needed to wrap a copy of that array in a String object. Just return a pointer to that array. Make the pointer const if you don't want the caller to be able to change the array.