Using a Button to Increase a Number in a TextField

I am creating an App and it crashes when I click the button to increase the value in a text field by 1. I am very tired and maybe I am not looking at this correctly. This is a button click event.

I have placed everything in a while loop that will never end. Then the ifs will increase the value by 1 in the int and then store it into a string that will set the value to the text box. I will also be including a decrease button to the the reverse.

 int SetUP = Integer.parseInt(findTxtComp().getText());
String SetUp;
SetUp = String.valueOf(SetUP);

int ChstSetLoop;
ChstSetLoop = 1;

        while(ChstSetLoop == 1){
    if(SetUp.equals("0")){

        SetUP = 1;
        SetUp = String.valueOf(SetUP);

        findTxtComp().setText(SetUp);
    }
    if(SetUp.equals("1")){

        SetUP = 2;
        SetUp = String.valueOf(SetUP);

        findTxtComp().setText(SetUp);
    }
    if(SetUp.equals("2")){

        SetUP = 3;
        SetUp = String.valueOf(SetUP);

        findTxtComp().setText(SetUp);
    }
    if(SetUp.equals("3")){

        SetUP = 4;
        SetUp = String.valueOf(SetUP);

        findTxtComp().setText(SetUp);
    }
    if(SetUp.equals("4")){

        SetUP = 5;
        SetUp = String.valueOf(SetUP);

        findTxtComp().setText(SetUp);
        SetUP = 0;
    }

    else{


    }
        }