Why Does My javax.swing Timer Repeat but My ActionListener Doesn\'t Update the Color of My Text Field?

javax.swing Timer Repeats Successfully, but ActionListener Fails to Respond

In this code snippet, the author aims to alternate the background color of a text field using a flashing effect. The timer setup appears to be functioning correctly, repeating the actions outlined in the Flash class. However, the desired color change is only observed during the initial alternation.

Upon further inspection, it becomes evident that the issue lies not with the timer's repeated execution but with the lack of visual updates despite the intended color changes. To resolve this issue, it is crucial to ensure that the changes made to the text field's background color are reflected in the display.

One effective approach is to override the paintComponent method in a custom panel class that encapsulates the text field. Within this method, the text should be rendered with the updated background color. This mechanism allows for continuous updates as the timer triggers color changes.

Here's a modified example that incorporates this approach:

<code class="java">public class FlashingPanel extends JPanel {

    private javax.swing.Timer timer;
    private JTextField textField;
    private boolean flashing = false;

    public FlashingPanel() {
        textField = new JTextField(10);
        add(textField);

        timer = new javax.swing.Timer(1000, this);
        timer.start();
    }

    @Override
    protected void paintComponent(Graphics g) {
        super.paintComponent(g);

        if (flashing) {
            textField.setBackground(Color.white);
        } else {
            textField.setBackground(Color.pink);
        }

        flashing = !flashing;
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        repaint();
    }

}</code>

In this enhanced code, the paintComponent method is overridden to directly apply the background color change to the text field, ensuring a visual update at every interval. As a result, the text field's background color will flash repeatedly and continuously as intended.

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