trying to break a while loop with a switch case inside switch case

Question

I am receiving some data from an USB component, component will send me continuous data, if I have received the data I have to stop reading the data myself and the component will not stop sending data, I am trying to break the loop if I received some key I tried using boolean, but it is not terminating the loop.

 boolean shouldBreak = false;

    switch(msg.what)
    {               

    case USBAccessoryWhat:
    switch(((USBAccessoryManagerMessage)msg.obj).type) {
    case READ:
        if(accessoryManager.isConnected() == false) {
            return;
        }
        while(true) {
            if(accessoryManager.available() < 2) {
                break;
            }

            switch(commandPacket[0]){
                case 0:
                    test = Integer.toString(commandPacket[0]) + ", " + Integer.toString(commandPacket[1]);
                    Test_one(test);
                break;
                case 1:
                    test = Integer.toString(commandPacket[0]) + ", " + Integer.toString(commandPacket[1]);
                    Test_one(test);
                break;
                case 2:
                    test = Integer.toString(commandPacket[0]) + ", " + Integer.toString(commandPacket[1]);
                    Test_one(test);
                    shouldBreak = true; // have to break here
                break;
                default:
                break;
            } 
             if (shouldBreak) break; //To break this while
        }
        break;

    }
    break;
    }

What part isn't working? From what you've written the loop won't break only if case 0 or case 1 is true and we never reach case 2. — Aakash Verma, Jun 30 '17 at 09:49
where i have marked as "//have to break here" i have to stop that while loop there. — Pattatharasu Nataraj, Jun 30 '17 at 09:50
There is no need to change `while(true)`. I feel the problem is with how you're handling cases. — Aakash Verma, Jun 30 '17 at 09:53
ok i will try, but shouldBreak will become true after that case 2 executes, how does it works? — Pattatharasu Nataraj, Jun 30 '17 at 09:54
Yes, it will become true. I feel that case 2 is never getting executed and it only goes for other cases or default. — Aakash Verma, Jun 30 '17 at 09:55
It's a lot easier to control this kind of thing if you nicely place each [switch statement]/[loop body] in its own function. It lets you take advantage of `return` without having to add all kinds of flags or labels for breaking. — byxor, Jun 30 '17 at 10:00
no, case 2 is working, the statement before break is working, it is reaching case 2. @AakashVerma — Pattatharasu Nataraj, Jun 30 '17 at 10:01

score 2 · Accepted Answer · answered Jun 30 '17 at 09:51

2

Try replacing while(true) with while(!shouldBreak) as a break statement only breaks out of the inner-most loop / switch / while etc.

For more details see e.g. Difference between break and continue statement

answered Jun 30 '17 at 09:51

Erich Schreiner

2,038
1
14
24

score 1 · Answer 2 · answered Jun 30 '17 at 09:51

1

Just use your flag in the while check:

switch ()
  case  
    bool shouldLoop = true
    while (shouldLoop)
      switch
        case 
          if 
            shouldLoop = false

answered Jun 30 '17 at 09:51

Vincent Mimoun-Prat

28,208
16
81
124

score 1 · Answer 3 · answered Jun 30 '17 at 10:31

1

Try using label with the while loop as below :

label:
    While()
    {
      for()
      {
         break label;
      }
    }

answered Jun 30 '17 at 10:31

Onur Akan

41
10

trying to break a while loop with a switch case inside switch case

3 Answers3