Update Jlabel with regressive count

Question

I have a For that makes a countdown, but when I will pass the value to the Label it only takes the last value of the loop.

This is my method:

public static void contagemRegressiva(){

        System.out.println("Start");
        int i=0;
        for( i=10;i>=0;i--){
            //label
           numero[0].setText(""+i);
        }

    }

The result of Label goes straight to zero.

Answer 1

This is probably because the code runs so fast that you can only see the last value.

The ideal would be to set a Timer to run every 1 second and then update the label.

You can see how to use the class Timer in this my other answer. Just add a command to update the label where seconds are down.

Answer 2

As @utluiz said this is because your code runs fast, the value is changing but you can’t see that change because it’s so fast...

Inserts this code line:

Thread.sleep(1000); //faz com que o teu programa adormeça durante 1 segundo

attention: you must treat the exception in the possibility of being launched:

try {
    Thread.sleep(1000);
} catch (InterruptedException e) {
    e.printStackTrace();
    // handle the exception...        
    // For example consider calling Thread.currentThread().interrupt(); here.
}