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Thread: Java GUI Calculater

  1. #1
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    Default Java GUI Calculater

    Hey this is my first post, I need some help with making a GUI Calculator, this is a extract from the code, I make the variables "num1" and "operator" in the PlusAction but when I try use them in the EqualsAction it doesn't reconise them and cant find them, PLEASE HELP


    private void jBtnPlusActionPerformed(java.awt.event.ActionEvent evt) {

    double num1 = Double.parseDouble (this.jTxtInput.getText());
    String operator = "+";
    this.jTxtInput.setText("");

    }


    private void jBtnEqualsActionPerformed(java.awt.event.ActionEve nt evt) {
    Double num2 = Double.parseDouble(this.jTxtInput.getText());
    Double ans=0.0;
    if(operator.equals("+"))
    { ans = num1 + num2;
    }


  2. #2
    Crazy Cat Lady KevinWorkman's Avatar
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    Default Re: Java GUI Calculater

    What you've just described is the appropriate behavior. If you create a variable inside a block, like an if statement or an actionPerformed() method, that variable won't be visible outside of that method.

    You might have to rethink your design a bit, or at least when you declare those variables.
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