Question

我无法理解，我怎么能这样做，如果点击按钮，它只会让Playerlevel一次性升级并升级。直到没有钱？

1.Try

 if(ae.getActionCommand().equals("Upgrade LVL")) {  
                if (car.Playerlevel == 1){
                    if (car.money >= 2){
                        car.money -= 2;
                        car.Playerlevel +=1;
                        JOptionPane.showMessageDialog (null, "You have gained 1 Player Level", "Congralations", JOptionPane.INFORMATION_MESSAGE);
                        }
                    if (car.money < 2){
                        JOptionPane.showMessageDialog (null, "You dont have enought money. This Upgrade costs 100", "No Money", JOptionPane.ERROR_MESSAGE);}                
                    }           
                if (car.Playerlevel == 2){
                    if (car.money >= 2){
                        car.money -= 2;
                        car.Playerlevel +=1;
                        JOptionPane.showMessageDialog (null, "You have gained 2 Player Level", "Congralations", JOptionPane.INFORMATION_MESSAGE);}
                    if (car.money < 2){
                        JOptionPane.showMessageDialog (null, "You dont have enought money. This Upgrade costs 200", "No Money", JOptionPane.ERROR_MESSAGE);}                
                    }
                if (car.Playerlevel == 3){
                    if (car.money >= 2){
                        car.money -= 2;
                        car.Playerlevel +=1;
                        JOptionPane.showMessageDialog (null, "You have gained 3 Player Level", "Congralations", JOptionPane.INFORMATION_MESSAGE);}
                    if (car.money < 2){
                        JOptionPane.showMessageDialog (null, "You dont have enought money. This Upgrade costs 300", "No Money", JOptionPane.ERROR_MESSAGE);}                
                    }
                if (car.Playerlevel == 4){
                    if (car.money >= 2){
                        car.money -= 2;
                        car.Playerlevel +=1;
                        JOptionPane.showMessageDialog (null, "You have gained 4 Player Level", "Congralations", JOptionPane.INFORMATION_MESSAGE);}
                    if (car.money < 2){
                        JOptionPane.showMessageDialog (null, "You dont have enought money. This Upgrade costs 400", "No Money", JOptionPane.ERROR_MESSAGE);}                
                    }
                if (car.Playerlevel == 5){
                    if (car.money >= 2){
                        car.money -= 2;
                        car.Playerlevel +=1;
                        JOptionPane.showMessageDialog (null, "You have gained 5 Player Level", "Congralations", JOptionPane.INFORMATION_MESSAGE);}
                    if (car.money < 2){
                        JOptionPane.showMessageDialog (null, "You dont have enought money. This Upgrade costs 500", "No Money", JOptionPane.ERROR_MESSAGE);}                
                    }
                if (car.Playerlevel == 6){
                    if (car.money >= 2){
                        car.money -= 2;
                        car.Playerlevel +=1;
                        JOptionPane.showMessageDialog (null, "You have gained 6 Player Level", "Congralations", JOptionPane.INFORMATION_MESSAGE);}
                    if (car.money < 2){
                        JOptionPane.showMessageDialog (null, "You dont have enought money. This Upgrade costs 600", "No Money", JOptionPane.ERROR_MESSAGE);}                
                    }
                if (car.Playerlevel == 7){
                    if (car.money >= 2){
                        car.money -= 2;
                        car.Playerlevel +=1;
                        JOptionPane.showMessageDialog (null, "You have gained 7 Player Level", "Congralations", JOptionPane.INFORMATION_MESSAGE);}
                    if (car.money < 2){
                        JOptionPane.showMessageDialog (null, "You dont have enought money. This Upgrade costs 700", "No Money", JOptionPane.ERROR_MESSAGE);}                
                    }
                if (car.Playerlevel == 8){
                    if (car.money >= 2){
                        car.money -= 2;
                        car.Playerlevel +=1;
                        JOptionPane.showMessageDialog (null, "You have gained 8 Player Level", "Congralations", JOptionPane.INFORMATION_MESSAGE);}
                    if (car.money < 2){
                        JOptionPane.showMessageDialog (null, "You dont have enought money. This Upgrade costs 800", "No Money", JOptionPane.ERROR_MESSAGE);}                
                    }
                if (car.Playerlevel == 9){
                    if (car.money >= 2){
                        car.money -= 2;
                        car.Playerlevel +=1;
                        JOptionPane.showMessageDialog (null, "You have gained 9 Player Level", "Congralations", JOptionPane.INFORMATION_MESSAGE);}
                    if (car.money < 2){
                        JOptionPane.showMessageDialog (null, "You dont have enought money. This Upgrade costs 900", "No Money", JOptionPane.ERROR_MESSAGE);}                
                    }
                if (car.Playerlevel == 10){
                        JOptionPane.showMessageDialog (null, "You have gained MAX Player Level", "Congralations", JOptionPane.INFORMATION_MESSAGE);}                            
            }

2.Try

if(ae.getActionCommand().equals("Upgrade LVL")) {           
            for (int i =0; i <11; i++){                 
                   if (car.Playerlevel == i){
                    if (car.money >= i*2){
                        car.money -= i*2;
                        car.Playerlevel +=1;                   
                        JOptionPane.showMessageDialog (null, "You have purchased " + i + " Player level.", "Congralations", JOptionPane.INFORMATION_MESSAGE);}                          
                    else{                           
                        JOptionPane.showMessageDialog (null, "You dont have enought money. This Upgrade costs 100*lvl", "No Money", JOptionPane.ERROR_MESSAGE);}               
                   }
            }
        }

这些尝试都没有，不起作用。按下时，我只需按一次按钮工作。我试着刹车;但它也没有奏效。

Answer 1

实现这一目标的一种简单方法是恢复循环。而不是

 for (int i =0; i <11; i++)

使用

 for (int i=10; i>= 0; i--)

问题是你在迭代时改变了playerLevel变量。我的上述想法是有效的，因为你只会增加水平而不会减少它们。更通用的方法是将结果存储在局部变量中，并在循环后使用它来设置playerLevel。

实际上，如果你的循环并不像你展示的循环那么复杂，你也可以删除循环并使用playerLevel而不是i。

Java JButton只需要工作一次

1 个答案: