无法实例化我自己的 class：没有匹配函数来调用 'DHT::DHT()'

Question

我正在编写一个 Arduino 项目并尝试将我自己的 class 包裹在 DHT（传感器）库（https://github.com/adafruit/DHT-sensor-library/blob/master/examples/DHT_Unified_Sensor/DHT_Unified_Sensor.ino or that https://github.com/adafruit/DHT-sensor-library/blob/master/examples/DHTtester/DHTtester.ino）中。

我想用函数抽象出我自己的库，并用它来学习 C++。

但是当我尝试实例化我自己的 class 时遇到问题：

lib/Hythe/Hythe.cpp: In constructor 'Hythe::Hythe(uint8_t, uint8_t)':
lib/Hythe/Hythe.cpp:3:47: error: no matching function for call to 'DHT::DHT()'
 Hythe::Hythe(uint8_t dht_pin, uint8_t dht_type)

谁能告诉我如何在我自己的 class 中声明、实例化和调用 DHT class？ 当我实施 DHT

main.cpp

#include "Hythe.h"
Hythe hythe(HYTHE_PIN, HYTHE_TYPE); // here I instantiate the sensor.

void setup()
{
  hythe.getSensorInfo();
}

Hythe.h


#include "SPI.h"
#include "Wire.h"
#include <DHT.h>

class Hythe
{
private:
    float temperature;
    float humidity;
    uint32_t delayMS;
public:
    Hythe(uint8_t, uint8_t);        // init with PIN and TYPE
    DHT _dht; // THIS IS CAUSING THE ERROR
    // (It's in the header file. I simply wanna declare it and
    // call it in the cpp file later).
    // When I remove this line I get: 
    // "error: '_dht' was not declared in this scope"

    unsigned char getTemperature(); // read the temperature
    void getSensorInfo();           // returns sensor info

};

Hythe.cpp

#include "Hythe.h"

Hythe::Hythe(uint8_t dht_pin, uint8_t dht_type)
{
    Serial.print(dht_pin);
    _dht = DHT(dht_pin, dht_type);
}

unsigned char Hythe::getTemperature()
{
    return 0;
}

void Hythe::getSensorInfo()
{
    Serial.println(F("------------------------------------"));
    Serial.println(F("Temperature Sensor"));
}

Answer 1

正如 Vlad 指出的那样，DHT 没有默认构造函数。你想使用 initializer list 来避免调用默认构造函数。这样就可以在初始化列表中直接调用DHT的构造函数了

Hythe::Hythe(uint8_t dht_pin, uint8_t dht_type): _dht(dht_pin, dht_type)
{
    Serial.print(dht_pin);
}

无法实例化我自己的 class：没有匹配函数来调用 'DHT::DHT()'

Cannot instantiate my own class: no matching function for call to 'DHT::DHT()'

refactoring

arduino

arduino-c++