flutter - 背后的逻辑是什么，什么onPressed带入Flutter？

Question

    void moveToReg()
    {
      //it is a function
    }

  onPressed: moveToReg  //It works 
  onPressed: moveToReg(); //It gives an error 

I am an absolute beginner and I want to ask why onPressed takes function without Parentheses ?

Answer 1

不带括号的onPressed take函数将引用(指针)传递给该函数moveToreg到onPressed参数，只是因为onPressed和moveToreg期望的回调参数兼容。