Question

有人可以解释一下为什么我的循环从0到7？我只需要在前3个案例中获得，但程序正在通过所有..代码在show（）方法中。

for(brojac=0; brojac<3; brojac++){

    switch(brojac){
    case 1:
        figura1.setPosition(pomx[random], pomy[random]);
        stage.addActor(figura1);
        System.out.println("1");
    case 2:
        figura2.setPosition(pomx[random], pomy[random]);
        stage.addActor(figura2);
        System.out.println("2");
    case 3:
        figura3.setPosition(pomx[random], pomy[random]);
        stage.addActor(figura3);
        System.out.println("3");
    case 4:
        figura4.setPosition(pomx[random], pomy[random]);
        stage.addActor(figura4);
        System.out.println("4");
    case 5:
        figura5.setPosition(pomx[random], pomy[random]);
        stage.addActor(figura5);
        System.out.println("5");
    case 6:
        figura6.setPosition(pomx[random], pomy[random]);
        stage.addActor(figura6);
        System.out.println("6");
    case 7:
        figura7.setPosition(pomx[random], pomy[random]);
        stage.addActor(figura7);
        System.out.println("7");

    }
}

Answer 1

因为缺少休息时间。在每个案例之后，您需要break关键字。有关详细说明，请参阅switch statement java tutorial

e.g。

for(brojac=0; brojac<3; brojac++){

switch(brojac){
case 1:
    figura1.setPosition(pomx[random], pomy[random]);
    stage.addActor(figura1);
    System.out.println("1");
    break; /// Break here

case 2:
    figura2.setPosition(pomx[random], pomy[random]);
    stage.addActor(figura2);
    System.out.println("2");
    break; /// Break here
case 3:
    figura3.setPosition(pomx[random], pomy[random]);
    stage.addActor(figura3);
    System.out.println("3");
    break; /// Break here
case 4:
    figura4.setPosition(pomx[random], pomy[random]);
    stage.addActor(figura4);
    System.out.println("4");
    break; /// Break here
case 5:
    figura5.setPosition(pomx[random], pomy[random]);
    stage.addActor(figura5);
    System.out.println("5");
    break; /// Break here
case 6:
    figura6.setPosition(pomx[random], pomy[random]);
    stage.addActor(figura6);
    System.out.println("6");
    break; /// Break here
case 7:
    figura7.setPosition(pomx[random], pomy[random]);
    stage.addActor(figura7);
    System.out.println("7");
    break; /// Break here
}
}

否则，如果上述案例之一被评估为真，则将执行其他案例。

Answer 2

这就是Java's switch陈述的工作原理。

一旦其中一个匹配，他们就会“落伍”。您需要在所有情况之后添加break;。

for(brojac=0; brojac<3; brojac++){

    switch(brojac){
    case 1:
        figura1.setPosition(pomx[random], pomy[random]);
        stage.addActor(figura1);
        System.out.println("1");
        break;
    case 2:
        figura2.setPosition(pomx[random], pomy[random]);
        stage.addActor(figura2);
        System.out.println("2");
        break;
    case 3:
        figura3.setPosition(pomx[random], pomy[random]);
        stage.addActor(figura3);
        System.out.println("3");
        break;
    case 4:
        figura4.setPosition(pomx[random], pomy[random]);
        stage.addActor(figura4);
        System.out.println("4");
        break;
    case 5:
        figura5.setPosition(pomx[random], pomy[random]);
        stage.addActor(figura5);
        System.out.println("5");
        break;
    case 6:
        figura6.setPosition(pomx[random], pomy[random]);
        stage.addActor(figura6);
        System.out.println("6");
        break;
    case 7:
        figura7.setPosition(pomx[random], pomy[random]);
        stage.addActor(figura7);
        System.out.println("7");
        break;

    }
}

Switch执行所有case语句

2 个答案: