如何使我的代码与嵌套if语句一起使用

Question

I am creating a Interactive Story in Java. I am using Netbeans and Jswing to do all the GUI. I have an issue when nesting another if statement inside it doesn't allow the parameter...

if("Open Locker".equalsIgnoreCase(input)) {
     jLabel2.setText("You open your locker and tap your textbooks and they appear in your inventory. The warning bell rings.");
     jLabel3.setText("You remember your next class is World History...");

     if("Go to World History".equalsIgnoreCase(input)) {
          jLabel2.setText("You walk down the hallway realizing that you still have 45 minutes until");
          jLabel3.setText("class starts. You arrive in class and sit in your desk.");
     }
 }
 else {
     jLabel3.setText("You cannot do that right now.");
 }

Code Output

I can type in open locker and it works but when I type in go to world history it doesn't work it says you cannot do this right now...

Answer 1

I can type in open locker and it works but when I type in go to world history it doesn't work it says you cannot do this right now

This happens because your input hasn't been changed. To get into the first option you need to type Open Locker , then for the second you need to type Go to World History , but you already typed something in.

What you need to do is ask for another input after you go into the first if statement:

if("Open Locker".equalsIgnoreCase(input)) {
     jLabel2.setText("You open your locker and tap your textbooks and they appear in your inventory. The warning bell rings.");
     jLabel3.setText("You remember your next class is World History...");

     //ask for input

     if("Go to World History".equalsIgnoreCase(input)) {
          jLabel2.setText("You walk down the hallway realizing that you still have 45 minutes until");
          jLabel3.setText("class starts. You arrive in class and sit in your desk.");
     }
}

Answer 2

You need keep track of last input. Lets take variable isLockedOpened to do that

boolean isLockedOpened=false;

Now if locker is open set isLockedOpened=true. Next time when user inputs "Go to World History" then check input and isLockedOpened variable. Your code looks something like this:

if("Open Locker".equalsIgnoreCase(input)) {
     //set locker opened
     isLockedOpened=true;
     jLabel2.setText("You open your locker and tap your textbooks and they appear in your inventory. The warning bell rings.");
     jLabel3.setText("You remember your next class is World History...");
 }else if("Go to World History".equalsIgnoreCase(input) && isLockedOpened=true) {
          jLabel2.setText("You walk down the hallway realizing that you still have 45 minutes until");
          jLabel3.setText("class starts. You arrive in class and sit in your desk.");
 }
 else {
     jLabel3.setText("You cannot do that right now.");
     //isLockedOpened=false;//you can set this to true or false but understand what will happen in both case.
 }

Hope this will provide you little hint !!!