actionlistener無法正常工作

Question

嘗試調用方法getuserinput時出現錯誤。這是我破碎的代碼中的一小部分。

initialvelocitybutton.addActionListener(new ActionListener() { 
      public void actionPerformed(ActionEvent e) { 
     getuserinput(); //I am getting an error saying "The method getuserinput() is undefined for the type new ActionListener(){}" 
      } 
     }); 

static void getuserinput(){ //method to get users input 
       double initialvelocity = Double.parseDouble(
          JOptionPane.showInputDialog("please enter initial velocity")); //gets initial value of intiial velcoity 
       double angleoflaunch = Double.parseDouble(
          JOptionPane.showInputDialog("please enter angle of launch")); 
} 

Answer 1

getuserInput()被宣佈爲static。你必須參考它使用類名稱：NameOfYourClass.getuserInput();