Graph plotter with timer in java

Question

I'm working on a grapher that gets an expression like x^2 + t from the user and then will ask the user for range of x and t . t in here is the timer variable. so in x^2 + t the user for example will choose the -10 to 10 for x and 1 to 5 for t . now by clicking the draw button in GUI program the code will start plotting the expression from minimum t (1 in here) and after each second(or any time period) will increase the t value by one and draw the expression with new t (2 ,3 until it reaches the maximum range). how can make the event handler to do this? I have found a way to draw multiple graphs but I can't make a delay so the minimum to maximum . I know I should use timer but I don't know how to use in this part of the code

the Link for the whole code

this is the part of code in plotter class that should be changed :

// Grapher
    drawButton.addActionListener(new ActionListener() {
        public void actionPerformed(ActionEvent arg0) {

            try {

                String testSpring = null;
                String tVarString = null;

                for (int i = 0; i < 5; i++) {

                    testSpring = inputExpression;
                    tVarString = String.valueOf(i);
                    testSpring = testSpring.replaceAll("t", tVarString);

                    Equation equation = new Equation(testSpring);

                    graph.addEquation(equation);

                }
            }

            catch (EquationSyntaxException e) {

                e.printStackTrace();
            }

        }
    });

This is the picture of the program :

my priority is to make the program run just by clicking draw button but It would be better if this timer could be influence JSlider so the min and max of t would be min and max of Jslider and by clicking draw it would start drawing by every time slider knob would point at a value for t

Answer 1

Take a look at How to use Swing Timers

This will allow you to setup a callback at a regular interval, which is executed from within the context of the EDT, making it safe to update the UI from within

    public void actionPerformed(ActionEvent arg0) {

        Timer timer = new Timer(1000, new ActionListener() {
             private int iteration;
             @Override
             public void adtionPerformed(ActionEvent evt) {

                try {

                    String testSpring = null;
                    String tVarString = null;

                    testSpring = inputExpression;
                    tVarString = String.valueOf(iteration);
                    testSpring = testSpring.replaceAll("t", tVarString);

                    Equation equation = new Equation(testSpring);

                    graph.addEquation(equation);

                 } catch (EquationSyntaxException e) {
                    e.printStackTrace();
                } finally {
                     iteration++
                     if (iteration > 4) {
                         ((Timer)evt.getSource()).stop();
                     }
                }
            }
        });
        timer.start();

    }
});